Afrin Kamal is a board-certified gastroenterologist, who trained at Washington University in internal medicine, Cleveland Clinic in gastroenterology/hepatology, and most recently Stanford University in esophageal and motility diseases. Afrin shares a clinical passion in esophageal motility diseases with an an overlapping interest in health services and outcomes research.

Clinical Focus

  • Gastroenterology
  • Benign esophageal diseases
  • Esophageal motility

Academic Appointments

Boards, Advisory Committees, Professional Organizations

  • Trainee Committee member, American College of Gastroenterology (2018 - Present)

Professional Education

  • Fellowship: Stanford University Division of Gastroenterology and Hepatology (2019) CA
  • Fellowship: Cleveland Clinic Foundation Hospital (2018) OH
  • Board Certification: American Board of Internal Medicine, Gastroenterology (2018)
  • Residency: Washington University School Of Medicine Registrar (2014) MO
  • Board Certification, Gastroenterology, American Board of Internal Medicine (2018)
  • Board Certification: American Board of Internal Medicine, Internal Medicine (2014)
  • Medical Education: University of Missouri (2011) MO

Clinical Trials

  • Applying Nutrient Drink Test in Understanding Pathophysiology of CVS Not Recruiting

    Cyclic vomiting syndrome is a disorder characterized by nausea and vomiting, separated by periods without any symptoms. There is very little research on this field at this point and most doctors do not fully understand the disorder. The goal of this study is to assess how the stomach empties food. Participants will be asked to participate in this study because either (a) they have been diagnosed and/or treated for cyclic vomiting syndrome in the past, or (b) they are physically healthy. The study seeks to compare how a healthy person's stomach empties to how the stomach of someone with cyclic vomiting disorder empties.

    Stanford is currently not accepting patients for this trial.

    View full details

All Publications

  • Identification of gaps in the delivery of high-quality care of patients with eosinophilic esophagitis. Diseases of the esophagus : official journal of the International Society for Diseases of the Esophagus Njie, C., Richman, C., Rebhun, J., Achalu, S., Kamal, A. N., Otaki, F., Leiman, D. A., Kathpalia, P. 2024


    Quality indicators (QIs) are standardized metrics that can be used to quantify health care delivery and identify important areas for practice improvement. Nine QIs pertaining to the diagnosis and management of eosinophilic esophagitis (EoE) were recently established. We therefore aimed to identify existing gaps in care using these QIs. This is a retrospective, multicenter study utilizing recently established EoE QIs to evaluate practice patterns among adult gastroenterologists in the diagnosis and management of EoE. Three patient cohorts of 30 patients each presenting with dysphagia, food impaction, and new diagnosis of EoE, respectively, were obtained, yielding 120 patients per site to assess for every QI. Summary statistics were reported across two main themes: diagnosis and management. Subsequent analysis of gaps in care was then performed. The domain of diagnosis of EoE (QI 1 and 2) had the most notable gap in care with only 55% of the presenting patients undergoing appropriate evaluation for EoE. The domain of management of EoE had overall higher QI fulfillment-however it also contained significant intra-category variation in care. Notably, while 79% of patients had clinical follow-up within 1year from remission, only 54% underwent surveillance endoscopy within 2years of remission. In contrast, 100% of patients with symptomatic strictures independent of histologic response underwent endoscopic dilation (QI 4). Management approaches for EoE are evolving and variation in care delivery exists. We identified significant gaps in both diagnosis of EoE especially amongst patients presenting with index food impaction and long term management of EoE, when retrospectively evaluating care patterns using newly established QIs. This is the first study of its kind to utilize these previously established QIs to objectively identify care gaps that exist in EoE amongst several institutions. These findings also highlight the importance of QIs and standardization of management of complex chronic diseases like EoE to help bridge these gaps and provide a framework to measure adherence to these best practices.

    View details for DOI 10.1093/dote/doae055

    View details for PubMedID 39007698

  • Quality Indicator Development for the Approach to Ineffective Esophageal Motility: A Modified Delphi Study. Journal of clinical gastroenterology Kamal, A. N., Kathpalia, P., Leiman, D. A., Bredenoord, A. J., Clarke, J. O., Gyawali, C. P., Katzka, D. A., Lazarescu, A., Pandolfino, J. E., Penagini, R., Roman, S., Savarino, E., Vela, M. F., Otaki, F. 2024


    Develop quality indicators for ineffective esophageal motility (IEM).IEM is identified in up to 20% of patients undergoing esophageal high-resolution manometry (HRM) based on the Chicago Classification. The clinical significance of this pattern is not established and management remains challenging.Using RAND/University of California, Los Angeles Appropriateness Methods, we employed a modified-Delphi approach for quality indicator statement development. Quality indicators were proposed based on prior literature. Experts independently and blindly scored proposed quality statements on importance, scientific acceptability, usability, and feasibility in a 3-round iterative process.All 10 of the invited esophageal experts in the management of esophageal diseases invited to participate rated 12 proposed quality indicator statements. In round 1, 7 quality indicators were rated with mixed agreement, on the majority of categories. Statements were modified based on panel suggestion, modified further following round 2's virtual discussion, and in round 3 voting identified 2 quality indicators with comprehensive agreement, 4 with partial agreement, and 1 without any agreement. The panel agreed on the concept of determining if IEM is clinically relevant to the patient's presentation and managing gastroesophageal reflux disease rather than the IEM pattern; they disagreed in all 4 domains on the use of promotility agents in IEM; and had mixed agreement on the value of a finding of IEM during anti-reflux surgical planning.Using a robust methodology, 2 IEM quality indicators were identified. These quality indicators can track performance when physicians identify this manometric pattern on HRM. This study further highlights the challenges met with IEM and the need for additional research to better understand the clinical importance of this manometric pattern.

    View details for DOI 10.1097/MCG.0000000000001963

    View details for PubMedID 38227852

  • Esophageal Function Testing Patterns in the Evaluation and Management of Lung Transplantation: Results of a National Survey. Journal of clinical gastroenterology Yamamoto, M., Kamal, A. N., Gabbard, S., Clarke, J., Gyawali, C. P., Leiman, D. A. 2023


    We surveyed esophageal motility laboratories affiliated with adult pulmonary transplant centers to determine esophageal function testing (EFT) practices.Gastroesophageal reflux and esophageal dysmotility are associated with worse lung transplant outcomes, yet no consensus guidelines for EFT exist in this population.A deidentified online survey was sent to gastrointestinal motility laboratory directors of 49 academic and community-affiliated medical centers that perform lung transplants. Practice characteristics, including annual lung transplant volume and institutional EFT practices pre-lung transplantation and post-lung transplantation were queried. Respondents were categorized by transplant volume into small and large programs based on median annual volume.Among 35 respondents (71% response rate), the median annual transplant volume was 37, and there were 18 large programs. Institutional EFT protocols were used pretransplant by 24 programs (68.6%) and post-transplant by 12 programs (34.2%). Among small and large programs, 52.9% and 72.2% always obtained high-resolution manometry before transplant, respectively. Endoscopy before transplant was performed more often in small programs (n=17, 100%) compared with large programs (n=15,83.3%). Pretransplant endoscopy (P=0.04), barium esophagram (P<0.01), and high-resolution manometry (P=0.04) were more common than post-transplant. In contrast, post-transplant reflux monitoring off-therapy was more common than pretransplant (P=0.01). In general, pulmonologists direct referrals for EFT and gastroenterology consultation (n=28, 80.0%), with symptoms primarily prompting testing.In the absence of established guidelines, substantial variability exists in pretransplant and post-transplant EFT, directed by pulmonologists. Standardized EFT protocols and gastroenterologist-directed management of esophageal dysfunction has potential to improve lung transplant outcomes.

    View details for DOI 10.1097/MCG.0000000000001955

    View details for PubMedID 38047589

  • Development and Validation of a Machine Learning System to Identify Reflux Events in Esophageal 24-hour pH/Impedance Studies. Clinical and translational gastroenterology Zhou, M. J., Zikos, T., Goel, K., Goel, K., Gu, A., Re, C., Rodriguez, D., Clarke, J. O., Garcia, P., Fernandez-Becker, N., Sonu, I., Kamal, A., Sinha, S. R. 2023


    INTRODUCTION: Esophageal 24-hour pH/impedance testing is routinely performed to diagnose gastroesophageal reflux disease (GERD). Interpretation of these studies is time-intensive for expert physicians and has high inter-reader variability. There are no commercially available machine learning tools to assist with automated identification of reflux events in these studies.METHODS: A machine learning system to identify reflux events in 24-hour pH/impedance studies was developed, which included an initial signal processing step and a machine learning model. Gold standard reflux events were defined by a group of expert physicians. Performance metrics were computed to compare the machine learning system, current automated detection software (Reflux Reader v6.1), and an expert physician reader.RESULTS: The study cohort included 45 patients (20/5/20 patients in the training/validation/test sets, respectively). Mean age was 51 (standard deviation [SD] 14.5) years, 47% of patients were male, and 78% of studies were performed off proton pump inhibitor (PPI). Comparing the machine learning system vs. current automated software vs. expert physician reader, AUC was 0.87 (95% CI 0.85-0.89) vs. 0.40 (95% CI 0.37-0.42) vs. 0.83 (95% CI 0.81-0.86), respectively; sensitivity was 68.7% vs. 61.1% vs. 79.4%, respectively; and specificity was 80.8% vs. 18.6% vs. 87.3%, respectively.DISCUSSION: We trained and validated a novel machine learning system to successfully identify reflux events in 24-hour pH/impedance studies. Our model performance was superior to that of existing software and comparable to that of a human reader. Machine learning tools could significantly improve automated interpretation of pH/impedance studies.

    View details for DOI 10.14309/ctg.0000000000000634

    View details for PubMedID 37578060

  • Esophageal Lichen Planus: A Descriptive Multicenter Report. Journal of clinical gastroenterology Aby, E. S., Eckmann, J. D., Abimansour, J., Katzka, D. A., Beveridge, C., Triggs, J. R., Dbouk, M., Abdi, T., Turner, K. O., Antunes, C., Zhuo, J., Kamal, A. N., Patel, P., Gyawali, C. P., Sloan, J. A. 2023


    To better understand the characteristics, treatment approaches, and outcomes of patients with esophageal lichen planus (ELP).ELP is a rare, often unrecognized and misdiagnosed disorder. Data on this unique patient population are currently limited to small, single-center series.A multicenter, retrospective descriptive study was conducted of adults diagnosed with ELP over a 5-year period, between January 1, 2015, and October 10, 2020, from 7 centers across the United States.Seventy-eight patients (average age 65 y, 86% female, 90% Caucasian) were included. Over half had at least 1 extraesophageal manifestation. Esophageal strictures (54%) and abnormal mucosa (50%) were frequent endoscopic findings, with the proximal esophagus the most common site of stricture. Approximately 20% had normal endoscopic findings. Topical steroids (64%) and/or proton pump inhibitors (74%) dominated management; endoscopic response favored steroids (43% vs. 29% respectively). Almost half of the patients required switching treatment modalities during the study period. Adjunctive therapies varied significantly between centers.Given its at times subtle clinical and endoscopic signs, a high index of suspicion and biopsy will improve ELP diagnosis, especially in those with extraesophageal manifestations. Effective therapies are lacking and vary significantly. Prospective investigations into optimal treatment regimens are necessary.

    View details for DOI 10.1097/MCG.0000000000001885

    View details for PubMedID 37436831

  • Tacrolimus-Induced Esophageal and Colon Ulcers ACG CASE REPORTS JOURNAL Vazquez-Reyes, R., Yeoh, A., Kamal, A. 2023; 10 (6)
  • Development and modification of a dysphagia question prompt list to improve patient-physician communication: Incorporating both esophageal expert and patient perspectives. Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society Achalu, S., Berry, R., Zhuo, J., Bredenoord, A. J., Clarke, J. O., Fass, R., Gyawali, C. P., Kahrilas, P. J., Katzka, D. A., Massey, B. T., Penagini, R., Roman, S., Savarino, E., Vela, M. F., Kamal, A. N. 2023: e14600


    Question prompt lists (QPLs) are structured sets of disease-specific questions, intended to encourage question-asking by patients and enhance patient-physician communication. To date, a dysphagia-specific QPL has not been developed for patients with esophageal dysphagia symptoms. We aim to develop a dysphagia-specific QPL incorporating both esophageal expert and patient perspectives, applying rigorous methodology.The QPL content was generated applying a two-round modified Delphi (RAND/UCLA) method among 11 experts. In round one, experts provided five answers to the prompts: "What general questions should patients ask when being seen for dysphagia?" and "What questions do I not hear patients asking but, given my experience, I believe they should be asking?" In round two, experts rated proposed questions on a 5-point Likert scale. Responses rated as "essential" or "important", determined by an a priori median threshold of ≥4.0, were accepted for inclusion. Subsequently, 20 patients from Stanford Health Care were enrolled to modify the preliminary QPL, to incorporate their perspectives and opinions. Patients independently rated questions applying the same 5-point Likert scale. At the end, patients were encouraged to propose additional questions to incorporate into the QPL by open-endedly asking "Are there questions we didn't ask, that you think we should?"Eleven experts participated in both voting rounds. Of 85 questions generated from round one, 60 (70.6%) were accepted for inclusion, meeting a median value of ≥4.0. Questions were combined to reduce redundancy, narrowing down to 44 questions. Questions were categorized into the following six themes: 1. "What is causing my dysphagia?"; 2. "Associated symptoms"; 3. "Testing for dysphagia"; 4. "Lifestyle modifications"; 5. "Treatment for dysphagia"; and 6. "Prognosis". The largest number of questions covered "What is causing my dysphagia" (27.3%). Twenty patients participated and modified the QPL. Of the 44 questions experts agreed were important, only 30 questions (68.2%) were accepted for inclusion. Six patients proposed 10 additional questions and after incorporating the suggested questions, the final dysphagia-specific QPL created by esophageal experts and modified by patients consisted of 40 questions.Incorporating expert and patient perspectives, we developed a dysphagia-specific QPL to enhance patient-physician communication. Our study highlights importance of incorporating patient perspective when developing such a communication tool. Further studies will measure the impact of this communication tool on patient engagement.

    View details for DOI 10.1111/nmo.14600

    View details for PubMedID 37122123

  • A Delphi Method for Development of a Barrett's Esophagus Question Prompt List as a Communication Tool for Optimal Patient-physician Communication. Journal of clinical gastroenterology Kamal, A. N., Wang, C. J., Triadafilopoulos, G., Diehl, D. L., DuCoin, C., Dunst, C. M., Falk, G., Iyer, P. G., Katzka, D. A., Konda, V. J., Muthusamy, R., Otaki, F., Pleskow, D., Rubenstein, J. H., Shaheen, N. J., Sharma, P., Smith, M. S., Sujka, J., Swanstrom, L. L., Tatum, R. P., Trindade, A. J., Ujiki, M., Wani, S., Clarke, J. O. 2023


    BACKGROUND METHODS: The question prompt list content was derived through a modified Delphi process consisting of 3 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of Barrett's esophagus" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" Questions were reviewed and categorized into themes. In round 2, experts rated questions on a 5-point Likert scale. In round 3, experts rerated questions modified or reduced after the previous rounds. Only questions rated as "essential" or "important" were included in Barrett's esophagus question prompt list (BE-QPL). To improve usability, questions were reduced to minimize redundancy and simplified to use language at an eighth-grade level (Fig. 1).RESULTS: Twenty-one esophageal medical and surgical experts participated in both rounds (91% males; median age 52 years). The expert panel comprised of 33% esophagologists, 24% foregut surgeons, and 24% advanced endoscopists, with a median of 15 years in clinical practice. Most (81%), worked in an academic tertiary referral hospital. In this 3-round Delphi technique, 220 questions were proposed in round 1, 122 (55.5%) were accepted into the BE-QPL and reduced down to 76 questions (round 2), and 67 questions (round 3). These 67 questions reached a Flesch Reading Ease of 68.8, interpreted as easily understood by 13 to 15 years olds.CONCLUSIONS: With multidisciplinary input, we have developed a physician-derived BE-QPL to optimize patient-physician communication. Future directions will seek patient feedback to distill the questions further to a smaller number and then assess their usability.

    View details for DOI 10.1097/MCG.0000000000001832

    View details for PubMedID 36753462

  • Nutrient Drink Test to Assess Gastric Accommodation in Cyclic Vomiting Syndrome: Single-blinded Parallel Grouped Prospective Study. Journal of neurogastroenterology and motility Kamal, A. N., Harris, K. B., Sarvapalli, S., Sayuk, G. S., Gyawali, C. P., Gabbard, S. 2023; 29 (1): 65-71


    Background/Aims: Cyclic vomiting syndrome (CVS) is characterized by episodes of nausea and vomiting, separated by symptom-free intervals. The pathogenesis of CVS is poorly understood. Limited data exist on evaluating impaired gastric accommodation as a mechanistic means for symptoms. We aim to determine if CVS patients demonstrate impaired gastric accommodation applying a nutrient drink test (NDT) protocol.Methods: Through this single-blinded pilot clinical trial, patients with CVS per Rome IV critera and healthy controls were assessed for presence of impaired gastric accommodation by administering an established NDT protocol. Statistical analysis was performed, with data presented as medians and interquartile range.Results: Eleven CVS patients and 15 healthy controls participated in the study between January 2018 and October 2018. Median age was 42.0 years and 37.0 years; majority of subjects were female, 72.7% and 73.3%, respectively. Demographics were similar between CVS and healthy controls. Almost all healthy controls (93.3%) ingested the complete 500 mL protocol, whereas a smaller proportion (72.7%) were able to complete all 4 doses in the CVS group (P = 0.188). Post-prandial visual analogue scale scores of nausea and abdominal pain were found to be significantly higher in CVS patients compared to healthy controls.Conclusions: To our knowledge, this is the first NDT protocol in CVS evaluating the role of impaired gastric accommodation and hypersensitivity as a possible pathophysiologic mechanism. Findings from this study suggest the presence of gastric hypersensitivity in a subset of CVS patients. These results provide the foundational data necessary for future larger testing of NDT and diagnostic accuracy in CVS.

    View details for DOI 10.5056/jnm22013

    View details for PubMedID 36606437

  • Quality Indicators for the Diagnosis and Management of Eosinophilic Esophagitis. The American journal of gastroenterology Leiman, D. A., Kamal, A. N., Otaki, F., Bredenoord, A. J., Dellon, E. S., Falk, G. W., Fernandez-Becker, N. Q., Gonsalves, N., Hirano, I., Katzka, D. A., Peterson, K., Yadlapati, R., Kathpalia, P. 2023


    Despite best practice recommendations for managing eosinophilic esophagitis (EoE), variation in care exists.We used established methodology for quality indicator development to identify metrics to define quality for the treatment of EoE.Among 29 proposed quality indicator statements, 9 (31%) were adopted as highly valid across all categories. Two (22%) of these statements were identified as having existing or suspected quality gaps.We identified highly valid EoE quality indicators for adult gastroenterologists, which can be used for quality improvement with resulting benefits for patient outcomes.

    View details for DOI 10.14309/ajg.0000000000002138

    View details for PubMedID 36599135

  • Value of 96-hour ambulatory esophageal pH monitoring in the assessment of patients with refractory acid reflux symptoms and their response to anti-reflux diet. Diseases of the esophagus : official journal of the International Society for Diseases of the Esophagus Triadafilopoulos, G., Kamal, A., Clarke, J. O. 2022


    Ambulatory esophageal pH monitoring is a diagnostic tool in patients with heartburn and regurgitation. The aim of this study is to evaluate 96-hour esophageal pH monitoring in patients with gastroesophageal reflux disease (GERD), at baseline and under diet that impedes GER. We hypothesized that diet would potentially reduce pathologic acid exposure time (AET). Retrospective series of 88 patients with GERD undergoing wireless 96-hour pH monitoring. Two-day (48hours) tandem periods, one on liberal, followed by another on restricted diet assessed esophageal AET. Primary end point was >30% reduction in AET while on anti-GER diet. Of the 88 patients, 16 were excluded because of probe migration. Endoscopy and biopsies assessed erosive esophagitis (EE) and Barrett's esophagus (BE), or normal esophagus. Abnormal AET (% pH<4.0≥6) further defined nonerosive reflux disease (NERD), whereas normal AET (% pH<4.0<6) with normal endoscopy defined patients as functional heartburn (FH). There were 6 patients with EE (n=5) and BE (n=1), 23 with NERD and 43 with FH. Anti-GER diet led to >30% reduction in AET in EE and NERD patients, but not in those with FH. Most patients (n=43/72; 60%) had FH and could have avoided acid suppression. Furthermore, (14/23; 61%) of patients with NERD completely normalized AET with diet, potentially negating acid suppression. Ninety-six-hour esophageal pH distinguishes GERD patients from those with FH. Fifty percent of EE/BE patients and 61% of those with NERD completely normalize AET with diet. If pathologic AET occurs despite diet, acid suppression is indicated.

    View details for DOI 10.1093/dote/doac102

    View details for PubMedID 36567531

  • Achalasia Quality Indicator Adherence. Digestive diseases and sciences Romanoff, E., Zhuo, J., Huang, A. C., Amador, D., Otaki, F., Kamal, A. N., Kathpalia, P., Leiman, D. A. 2022


    BACKGROUND: Quality indicators (QIs) are formal ways to track health care performance and outcomes, guide quality improvement, and identify gaps in care delivery. We developed twelve quality indicators for achalasia management which cover the domains of patient education, diagnosis, and treatment of achalasia.AIM: To determine adherence to established quality indicators for achalasia management.METHODS: We performed a retrospective, multicenter evaluation of care patterns for adult patients greater than 18years old with newly diagnosed achalasia from January 2018 to May 2020. A balanced random patient sample was obtained at four large academic medical centers. Independent electronic health record chart abstraction was performed using a standardized form to determine adherence to applicable QIs. Pooled and de-identified data were analyzed to identify gaps in care.RESULTS: A total of 120 patients were included and the overall adherence to applicable quality indicators across all centers was 86%. The median follow-up for all patients from time of diagnosis to end of study was 511days. Clinicians adhered to all applicable quality indicators in 49 patients (39%). The quality indicator domain with the poorest adherence was patient education (67%), with 50% of patients having had a documented discussion of the risks of gastroesophageal reflux disease following surgical or endoscopic myotomy.CONCLUSIONS: Gaps in the quality of achalasia care delivery were identified, the largest of which relates to patient education about treatment risks. These findings highlight a potential area for future quality improvement studies and form the basis for developing fully specified quality measures.

    View details for DOI 10.1007/s10620-022-07658-7

    View details for PubMedID 36459295

  • The Impact of Intermittent Fasting on Patients With Suspected Gastroesophageal Reflux Disease. Journal of clinical gastroenterology Jiang, Y., Sonu, I., Garcia, P., Fernandez-Becker, N. Q., Kamal, A. N., Zikos, T. A., Singh, S., Neshatian, L., Triadafilopoulos, G., Goodman, S. N., Clarke, J. O. 2022


    GOAL: The aim was to investigate the short-term impact of time restricted feeding on patients with suspected gastroesophageal reflux disease (GERD).BACKGROUND: Lifestyle modifications are often suggested, but the role of diet in GERD is unclear. Intermittent fasting is popular in the media and has demonstrated potential benefits with weight loss and inflammatory conditions as well as alterations in gastrointestinal hormones.STUDY: Patients who were referred for 96-hour ambulatory wireless pH monitoring off proton pump inhibitor to investigate GERD symptoms were screened for eligibility. Patients were instructed to maintain their baseline diet for the first 2 days of pH monitoring and switch to an intermittent fasting regimen (16 consecutive hour fast and 8h eating window) for the second 2 days. Objective measures of reflux and GERD symptom severity were collected and analyzed.RESULTS: A total of 25 participants were analyzed. 9/25 (36%) fully adhered to the intermittent fasting regimen, with 21/25 (84%) demonstrating at least partial compliance. Mean acid exposure time on fasting days was 3.5% versus 4.3% on nonfasting days. Intermittent fasting was associated with a 0.64 reduction in acid exposure time (95% CI: -2.32, 1.05). There was a reduction in GERD symptom scores of heartburn and regurgitation during periods of intermittent fasting (14.3 vs. 9.9; difference of -4.46, 95% CI: -7.6,-1.32).CONCLUSIONS: Initial adherence to time restricted eating may be difficult for patients. There is weak statistical evidence to suggest that intermittent fasting mildly reduces acid exposure. Our data show that short-term intermittent fasting improves symptoms of both regurgitation and heartburn.

    View details for DOI 10.1097/MCG.0000000000001788

    View details for PubMedID 36730832

  • Healthcare Disparities in Gastroesophageal Reflux Disease for Hispanic and Latino Americans: A Solution-Oriented Approach for Improvement. The American journal of gastroenterology Kamal, A. N., Wang, C. J., Triadafilopoulos, G., Clarke, J. O. 2022

    View details for DOI 10.14309/ajg.0000000000001976

    View details for PubMedID 36206196

  • Best Practices in Treatment of Laryngopharyngeal Reflux Disease: A Multidisciplinary Modified Delphi Study. Digestive diseases and sciences Kamal, A. N., Dhar, S. I., Bock, J. M., Clarke, J. O., Lechien, J. R., Allen, J., Belafsky, P. C., Blumin, J. H., Chan, W. W., Fass, R., Fisichella, P. M., Marohn, M., O'Rourke, A. K., Postma, G., Savarino, E. V., Vaezi, M. F., Carroll, T. L., Akst, L. M. 2022


    BACKGROUND: Laryngopharyngeal reflux (LPR) is a common otolaryngologic diagnosis. Treatment of presumed LPR remains challenging, and limited frameworks exist to guide treatment.METHODS: Using RAND/University of California, Los Angeles (UCLA) Appropriateness Methods, a modified Delphi approach identified consensus statements to guide LPR treatment. Experts independently and blindly scored proposed statements on importance, scientific acceptability, usability, and feasibility in a four-round iterative process. Accepted measures reached scores with≥80% agreement in the 7-9 range (on a 9-point Likert scale) across all four categories.RESULTS: Fifteen experts rated 36 proposed initial statements. In round one, 10 (27.8%) statements were rated as valid. In round two, 8 statements were modified based on panel suggestions, and experts subsequently rated 5 of these statements as valid. Round three's discussion refined statements not yet accepted, and in round four, additional voting identified 2 additional statements as valid. In total, 17 (47.2%) best practice statements reached consensus, touching on topics as varied as role of empiric treatment, medication use, lifestyle modifications, and indications for laryngoscopy.CONCLUSION: Using a well-tested methodology, best practice statements in the treatment of LPR were identified. The statements serve to guide physicians on LPR treatment considerations.

    View details for DOI 10.1007/s10620-022-07672-9

    View details for PubMedID 35995882

  • Model for multi-disciplinary, multi-institutional virtual learning: The Stanford Esophageal Virtual Collaborative Conference on benign esophageal diseases. Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society Kamal, A. N., Triadafilopoulos, G., Gyawali, C. P., Nguyen, L., Sayuk, G. S., Azagury, D. E., Tatum, R. P., Clarke, J. O. 2022: e14369

    View details for DOI 10.1111/nmo.14369

    View details for PubMedID 35340088

  • Intra-subject Variability in High Resolution Anorectal Manometry Using the London Classification: Diagnostic and Therapeutic Implications. Digestive diseases and sciences Triadafilopoulos, G., Clarke, J. O., Kamal, A., Neshatian, L. 2022


    This retrospective pilot study conducted on a community-based cohort of both men and women of various ages and underlying clinical presentations examined the durability and reproducibility of HR-ARM findings influencing their potential impact on clinical decision-making at the point of care (Jameson et al. in Br J Surg 81:1689-1692, 1994). The key finding of our study was that only a minority of patients who underwent repeat anorectal manometry as analyzed by the London Classification had stable manometric findings, raising questions regarding the validity of a single manometric measurement, as currently analyzed, for clinical decision-making.

    View details for DOI 10.1007/s10620-021-07373-9

    View details for PubMedID 35194706

  • Development of a Preliminary Question Prompt List as a Communication Tool for Adults With Achalasia: A Modified Delphi Study. Journal of clinical gastroenterology Zhuo, J., Triadafilopoulos, G., Bredenoord, A. J., Clarke, J. O., Fass, R., Gyawali, C. P., Hawn, M., Hwang, J. H., Kahrilas, P. J., Katzka, D. A., Low, D., Massey, B. T., Patel, D., Penagini, R., Roman, S., Savarino, E., Smout, A. J., Swanstrom, L., Tatum, R., Vela, M. F., Zaninotto, G., Kamal, A. N. 2022


    BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions that enhance patient-physician communication by encouraging patients to ask questions during consultations.AIM: The aim of this study was to develop a preliminary achalasia-specific QPL created by esophageal experts.METHODS: The QPL content was derived through a modified Delphi method consisting of 2 rounds. In round 1, experts provided 5 answers to the prompts "What general questions should patients ask when given a new diagnosis of achalasia" and "What questions do I not hear patients asking, but given my expertise, I believe they should be asking?" In round 2, experts rated questions on a 5-point Likert scale. Questions considered "essential" or "important" were accepted into the QPL. Feedback regarding the QPL was obtained in a pilot study wherein patients received the QPL before their consultation and completed surveys afterwards.RESULTS: Nineteen esophageal experts participated in both rounds. Of 148 questions from round 1, 124 (83.8%) were accepted into the QPL. These were further reduced to 56 questions to minimize redundancy. Questions were categorized into 6 themes: "What is achalasia," "Risks with achalasia," "Symptom management in achalasia," "Treatment of achalasia," "Risk of reflux after treatment," and "Follow-up after treatment." Nineteen patients participated in the pilot, most of whom agreed that the QPL was helpful (84.2%) and recommended its wider use (84.2%).CONCLUSIONS: This is the first QPL developed specifically for adults with achalasia. Although well-received in a small pilot, follow-up studies will incorporate additional patient feedback to further refine the QPL content and assess its usability, acceptability, and feasibility.

    View details for DOI 10.1097/MCG.0000000000001671

    View details for PubMedID 35180150

  • Question Prompt List as a Communication Tool for Adults with Gastroesophageal Reflux Disease Incorporation of Patients' Perspectives. Journal of clinical gastroenterology Kamal, A., Achkar, E., Carlson, D., Clarke, J., Fass, R., Gyawali, C. P., Katzka, D. A., Patel, D., Penagini, R., Rezaie, A., Roman, S., Savarino, E., Shaheen, N. J., Triadafilopoulos, G. 2021


    BACKGROUND: Question prompt lists (QPLs) are structured sets of disease-specific questions intended for patient use, enhancing the patient-physician communication by encouraging patients to ask relevant questions during a consultation. Recently, a preliminary 78 question gastroesophageal reflux disease (GERD) specific QPL was created by 12 esophageal experts through a modified Delphi (RAND/University of California, Los Angeles) technique. Patients' perspectives and opinions on each question, however, had not been accounted for in the preliminary expert' version.AIM: The aim was to modify a preliminary experts' QPL, specific to adults with GERD, following patient perspectives and opinions.METHODS: A preliminary GERD QPL was modified through patient input and opinions. Thirty-eight patients with a clinical diagnosis of GERD followed at Stanford University Esophageal Clinic between January and November 2019 were consented to modify the preliminary 78 question expert QPL version. After receiving the QPL in Qualtrics (Provo, UT) by a direct e-mail invitation, patients independently rated questions on a 5-point Likert scale, where 1="should not be included," 2="unimportant," 3="don't know/depends," 4="important," and 5="essential." Questions were accepted for inclusion in the QPL with an a priori interagreement of 80% ranking in the range of 4 to 5. At the end, patients were encouraged to propose additional questions to incorporate into the QPL by open-endedly asking "Are there questions we didn't ask, that you think we should?"RESULTS: Twenty-three patients with GERD (19 female, median age 64) fully participated and modified the existing QPL (60.5%). Of the 78 questions from the preliminary GERD QPL, 66 questions (84.6%) were accepted for inclusion. The question with the highest agreement among patients rating a question as essential consisted of "what habits, food, and drinks do I have to avoid?" (82.6%). Questions eliminated because of disagreement included "What is the natural history of GERD," "Do I have a high chance to die from my Barrett's?," and "Why are you prescribing an antidepressant to treat my GERD?" Nine patients suggested additional questions totaling to 16 separate questions, including "What type of surgeries are there to help GERD?," "What stage is my GERD?," "What are the odds/percentage of getting cancer from GERD?" Incorporating the suggested questions, the final GERD QPL-created by esophageal experts and modified by patients-consisted of 82 questions.CONCLUSION: Esophageal experts and GERD patients have a high level of agreement on important questions, though there is some variation in perspective. Future studies can simplify this list and measure the impact of a shared GERD QPL on patients' decisional conflict and perceived involvement in care.

    View details for DOI 10.1097/MCG.0000000000001613

    View details for PubMedID 34653066

  • The Stanford Multidisciplinary Swallowing Disorders Center. Clinical gastroenterology and hepatology : the official clinical practice journal of the American Gastroenterological Association Nandwani, M., Dewan, K., Starmer, H., Kamal, A. N., Clarke, J. O. 2021

    View details for DOI 10.1016/j.cgh.2021.04.025

    View details for PubMedID 33887474

  • Development of quality indicators for the diagnosis and management of achalasia. Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society Kamal, A. N., Kathpalia, P., Otaki, F., Bredenoord, A. J., Castell, D. O., Clarke, J. O., Falk, G. W., Fass, R., Prakash Gyawali, C., Kahrilas, P. J., Katz, P. O., Katzka, D. A., Pandolfino, J. E., Penagini, R., Richter, J. E., Roman, S., Savarino, E., Triadafilopoulos, G., Vaezi, M. F., Vela, M. F., Leiman, D. A. 2021: e14118


    BACKGROUND: The management of achalasia has improved due to diagnostic and therapeutic innovations. However, variability in care delivery remains and no established measures defining quality of care for this population exist. We aimed to use formal methodology to establish quality indicators for achalasia patients.METHODS: Quality indicator concepts were identified from the literature, consensus guidelines and clinical experts. Using RAND/University of California, Los Angeles (UCLA) Appropriateness Method, experts in achalasia independently ranked proposed concepts in a two-round modified Delphi process based on 1) importance, 2) scientific acceptability, 3) usability, and 4) feasibility. Highly valid measures required strict agreement (≧ 80% of panelists) in the range of 7-9 for across all four categories.KEY RESULTS: There were 17 experts who rated 26 proposed quality indicator topics. In round one, 2 (8%) quality measures were rated valid. In round two, 19 measures were modified based on panel suggestions, and experts rated 10 (53%) of these measures as valid, resulting in a total of 12 quality indicators. Two measures pertained to patient education and five to diagnosis, including discussing treatment options with risk and benefits and using the most recent version of the Chicago Classification to define achalasia phenotypes, respectively. Other indicators pertained to treatment options, such as the use of botulinum toxin for those not considered surgical candidates and management of reflux following achalasia treatment.CONCLUSIONS & INFERENCES: Using a robust methodology, achalasia quality indicators were identified, which can form the basis for establishing quality gaps and generating fully specified quality measures.

    View details for DOI 10.1111/nmo.14118

    View details for PubMedID 33720448

  • Severe gastroparesis is associated with an increased incidence of slow-transit constipation as measured by wireless motility capsule. Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society Radetic, M., Kamal, A., Rouphael, C., Kou, L., Lyu, R., Cline, M. 2020: e14045


    BACKGROUND: Dysmotility in one region of the gastrointestinal tract has been found to predispose patients to developing motility disorders in other gastrointestinal segments. However, few studies have evaluated the relationship between gastroparesis and constipation.METHODS: Retrospective review of 224 patients who completed 4-hour, solid-phase gastric emptying scintigraphy (GES), and wireless motility capsule (WMC) testing to evaluate for gastroparesis and slow-transit constipation, respectively. When available, anorectal manometry data were reviewed to evaluate for dyssynergic defecation. Patients were divided into two groups based on the results of the GES: 101 patients with normal gastric emptying and 123 patients with gastroparesis (stratified by severity). Differences in constipation rates were compared between the groups.KEY RESULTS: Slow-transit constipation was more common in the gastroparesis group, but statistical significance was not reached (42.3% vs 34.7%, p=0.304). Univariate logistical regression analysis found no association between slow-transit constipation and gastroparesis (OR 1.38, 95% CI 0.80-2.38, p=0.245) nor dyssynergic defecation and gastroparesis (OR 0.88, 95% CI 0.29-2.70, p=0.822). However, when stratifying gastroparesis based on severity, slow-transit constipation was found to be associated with severe gastroparesis (OR 2.45, 95% CI 1.20-5.00, p=0.014). This association was strengthened with the exclusion of patients with diabetes mellitus (OR 3.5, 95% CI 1.39-8.83, p=0.008) - a potential confounder.CONCLUSIONS & INFERENCES: Patients with severe gastroparesis (>35% gastric retention at the 4-hour mark on solid-phase GES) have an increased likelihood of having underlying slow-transit constipation. Dyssynergic defecation does not appear to be associated with gastroparesis (of any severity).

    View details for DOI 10.1111/nmo.14045

    View details for PubMedID 33231369

  • Patient Reported Outcomes and Objective Swallowing Assessments in a Multidisciplinary Dysphagia Clinic. The Laryngoscope Dewan, K., Clarke, J. O., Kamal, A. N., Nandwani, M., Starmer, H. M. 2020


    OBJECTIVES/HYPOTHESIS: Dysphagia encompasses a complex compilation of symptoms which often differ from findings of objective swallowing evaluations. The purpose of this investigation was to compare the results of subjective dysphagia measures to objective measures of swallowing in patients evaluated in a multidisciplinary dysphagia clinic.STUDY DESIGN: Prospective cohort study.METHODS: The study cohort included all patients evaluated in the multidisciplinary dysphagia clinic over 24months. Participants were evaluated by a multidisciplinary team including a laryngologist, gastroenterologist, and speech-language pathologist. Evaluation included a videofluoroscopic swallowing study (VFSS), fiberoptic endoscopic evaluation of swallowing (FEES), and transnasal esophagoscopy (TNE). Data collected included diet (FOIS), Eating Assessment Tool (EAT-10) score, Reflux symptom index (RSI) score, and the findings of the VFSS exam.RESULTS: A total of 75 patients were included in the analysis. The average EAT-10 score was 16.3±2.1, RSI was 21.4±0.6, and FOIS score was 6.0±1.33. VFSS revealed impairments in the oral phase in 40% of the cohort, pharyngeal in 59%, and esophageal in 49%. Abnormalities were noted in one phase for 32%, in 2 phases in 32%, and three phases in 18%. Patients with abnormal pharyngeal findings on VFSS had significantly higher EAT-10 scores (P = .04). Patients with abnormal oral findings on VFSS were noted to have significantly lower FOIS scores (P = .03).CONCLUSIONS: Data presented here demonstrate a relationship between patient reported symptoms and objective VFSS findings in a cohort of patients referred for multidisciplinary swallowing assessment suggesting such surveys are helpful screening tools but inadequate to fully characterize swallowing impairment.LEVEL OF EVIDENCE: 3 Laryngoscope, 2020.

    View details for DOI 10.1002/lary.29194

    View details for PubMedID 33103765

  • Type II Achalasia Is Increasing in Prevalence. Digestive diseases and sciences Zhou, M. J., Kamal, A., Freedberg, D. E., Markowitz, D., Clarke, J. O., Jodorkovsky, D. 2020


    BACKGROUND: Three manometric subtypes of achalasia were defined in the Chicago Classification approximately 10years ago: type I (aperistalsis), type II (pan-pressurization), and type III (spastic). Since the widespread use of this classification scheme, the evolving prevalence of these subtypes has not been elucidated. We aim to determine the prevalence of each subtype a decade after the adoption of the Chicago Classification.METHODS: This is a retrospective cohort analysis of patients diagnosed with achalasia on high-resolution manometry (HRM) at two major academic medical centers between 2015 and 2018. Patients were excluded if they had a diagnosis of another esophageal motility disorder, previously treated achalasia, or foregut surgery. Demographic data, manometric subtype, and esophageal dilatation grade on endoscopy were obtained. Prevalence of achalasia subtypes was compared with a published historical control population (2004-2007). Fischer's exact and t tests were used for analysis.RESULTS: Of 147 patients in the contemporary cohort and 99 in the historical control cohort, the prevalence of type I achalasia was 8% versus 21%, type II 63% versus 50%, and type III 29% versus 29%, respectively (p=0.01). The mean age in our population was 58years compared to 57years in the historical control, and the proportion of men 48% versus 47%, respectively (p=0.78). Mean endoscopic dilatation grade in the contemporary cohort was 1.5 for type I patients, 0.9 for type II, and 0.4 for type III, compared with 1.5, 0.6, and 0.4, respectively. Overall mean dilatation grade was 0.8 in our cohort versus 0.7 in the historical control (p=0.58).CONCLUSION: The prevalence of type II achalasia was significantly greater and prevalence of type I significantly less in our patient population compared to our predefined historical control. Other characteristics such as age and sex did not appear to contribute to these differences. Histopathological evidence has suggested that type II achalasia may be an earlier form of type I; thus, the increased prevalence of type II achalasia may be related to earlier detection of the disease. The adoption of HRM, widespread use of the Chicago Classification, and increased disease awareness in the past decade may be contributing to these changes in epidemiology.

    View details for DOI 10.1007/s10620-020-06668-7

    View details for PubMedID 33089487

  • Assessment of Gastric Emptying Times Between Pediatrics and Adults With Cyclic Vomiting Syndrome JOURNAL OF CLINICAL GASTROENTEROLOGY Kamal, A., Sarvepalli, S., Selvakumar, P., Lopez, R., Radhakrishnan, K., Gabbard, S. 2020; 54 (9): E89–E92


    Cyclic vomiting syndrome (CVS) is characterized by episodes of nausea and vomiting separated by symptom-free intervals. Rome IV guidelines have now distinguished CVS from other disorders such as cannabinoid hyperemesis. The pathogenesis of CVS, however, is poorly understood. Limited data exist on gastric emptying (GE) in patients with CVS. Therefore, the authors aim to measure the GE profile in pediatrics and adults with CVS.Patients with the diagnosis of CVS (per NASPGHAN and Rome IV) between December 1998 and March 2017 who underwent gastric emptying study (GES) and without documented cannabis use were included. Clinical features including demographics, medication use, and comorbidities were also recorded. Frequency of rapid, normal, and delayed emptying was reported, and multinomial univariate logistic regression was used to identify factors associated with each type of emptying.Sixty-seven subjects were included (50.7% female individuals, pediatrics n=15, adults n=52). At 2-hour retention, 40% of pediatric patients met criteria for rapid, 33.3% for normal, and 26.7% for delayed GE. In adults, 50% met criteria for rapid, 46.2% for normal, and 3.8% for delayed GE. For every 5-year increase in age, odds of rapid emptying on GES increased.(1) GE is predominantly rapid at 2 hours in pediatrics and adults with CVS. (2) Rapid GE seems to increase with age. (3) Current guidelines do not recommend GE in the initial management, however, further studies may play a role to help differentiate CVS from other functional gastric disorders.

    View details for DOI 10.1097/MCG.0000000000001352

    View details for Web of Science ID 000576509400003

    View details for PubMedID 32569030

  • The Role of Symptom Association Analysis in Gastroesophageal Reflux Testing. The American journal of gastroenterology Kamal, A. N., Clarke, J. O., Oors, J. M., Smout, A. J., Bredenoord, A. J. 2020


    Gastroesophageal reflux disease is characterized by the reflux of gastric contents into the esophagus with an estimated worldwide prevalence of 8%-33%. The current paradigm in gastroesophageal reflux disease diagnosis relies on recognition of symptoms and/or the presence of mucosal disease at the time of esophagogastroduodenoscopy. Recognition of symptoms, however, can arise with challenges, particularly when patients complain of less typical symptoms. Since first reported in 1969 by Spencer et al., the application of prolonged intraesophageal pH monitoring to identify pathologic reflux has evolved considerably. Utility of pH monitoring aims to investigate the degree of acid burden and frequency of reflux episode, and the relationship between symptoms and acid reflux events. This relationship is represented by either the Symptom Index, Symptom Sensitivity Index, Symptom Association Probability, or Ghillebert Probability Estimate. This article reviews symptom-association analysis during esophageal reflux testing, covering the literature on current methods of reflux testing, interpretation of symptom association, and practical issues that can arise during symptom analysis.

    View details for DOI 10.14309/ajg.0000000000000754

    View details for PubMedID 32740077

  • Mucosal impedance for esophageal disease: evaluating the evidence. Annals of the New York Academy of Sciences Clarke, J. O., Ahuja, N. K., Chan, W. W., Gyawali, C. P., Horsley-Silva, J. L., Kamal, A. N., Vela, M. F., Xiao, Y. 2020


    Impedance has traditionally been employed in esophageal disease as a means to assess bolus flow and reflux episodes. Recent and ongoing research has provided new and novel applications for this technology. Measurement of esophageal mucosal impedance, via either multichannel intraluminal impedance catheters or specially designed endoscopically deployed impedance catheters, provides a marker of mucosal integrity. Mucosal impedance has been shown to segregate gastroesophageal reflux disease (GERD) and eosinophilic esophagitis from non-GERD controls and may play a role in predicting response to reflux intervention. More data are needed with regard to other esophageal subgroups, outcome studies, and functional disease. Our paper reviews the history of impedance in esophageal disease, the means of assessing baseline and mucosal impedance, data with regard to the newly developed mucosal impedance probes, the clinical utility of mucosal impedance in specific clinical conditions, and limitations in our existing knowledge, along with suggestions for future studies.

    View details for DOI 10.1111/nyas.14414

    View details for PubMedID 32588457

  • The role of ambulatory 24-hour esophageal manometry in clinical practice. Neurogastroenterology and motility : the official journal of the European Gastrointestinal Motility Society Kamal, A. N., Clarke, J. O., Oors, J. M., Bredenoord, A. J. 2020: e13861


    High-resolution manometry revolutionized the assessment of esophageal motility disorders and upgraded the classification through the Chicago Classification. A known disadvantage of standard HRM, however, is the inability to record esophageal motility function for an extended time interval; therefore, it represents only a more snapshot view of esophageal motor function. In contrast, ambulatory esophageal manometry measures esophageal motility over a prolonged period and detects motor activity during the entire circadian cycle. Furthermore, ambulatory manometry has the ability to measure temporal correlations between symptoms and motor events. This article aimed to review the clinical implications of ambulatory esophageal manometry for various symptoms, covering literature on the manometry catheter, interpretation of findings, and relevance in clinical practice specific to the evaluation of non-cardiac chest pain, chronic cough, and rumination syndrome.

    View details for DOI 10.1111/nmo.13861

    View details for PubMedID 32391594

  • Long-term outcomes of per-oral endoscopic myotomy compared to laparoscopic Heller myotomy for achalasia: a single-center experience. Surgical endoscopy Podboy, A. J., Hwang, J. H., Rivas, H., Azagury, D., Hawn, M., Lau, J., Kamal, A., Friedland, S., Triadafilopoulos, G., Zikos, T., Clarke, J. O. 2020


    INTRODUCTION: Many centers have reported excellent short-term efficacy of per-oral endoscopic myotomy (POEM) for the treatment of achalasia. However, long-term data are limited and there are few studies comparing the efficacy of POEM versus Heller Myotomy (HM).AIMS: To compare the long-term clinical efficacy of POEM versus HM.METHODS: Using a retrospective, parallel cohort design, all cases of POEM or HM for achalasia between 2010 and 2015 were assessed. Clinical failure was defined as (a) Eckardt Score>3 for at least 4weeks, (b) achalasia-related hospitalization, or (c) repeat intervention. All index manometries were classified via Chicago Classification v3. Pre-procedural clinical, manometric, radiographic data, and procedural data were reviewed.RESULTS: 98 patients were identified (55 POEM, 43 Heller) with mean follow-up of 3.94years, and 5.44years, respectively. 83.7% of HM patients underwent associated anti-reflux wrap (Toupet or Dor). Baseline clinical, demographic, radiographic, and manometric data were similar between the groups. There was no statistical difference in overall long-term success (POEM 72.7%, HM 65.1% p=0.417, although higher rates of success were seen in Type III Achalasia in POEM vs Heller (53.3% vs 44.4%, p<0.05). Type III Achalasia was the only variable associated with failure on a univariate COX analysis and no covariants were identified on a multivariate Cox regression. There was no statistical difference in GERD symptoms, esophagitis, or major procedural complications.CONCLUSION: POEM and HM have similar long-term (4-year) efficacy with similar adverse event and reflux rates. POEM was associated with greater efficacy in Type III Achalasia.

    View details for DOI 10.1007/s00464-020-07450-6

    View details for PubMedID 32157405

  • Changes in high-resolution manometric diagnosis over time: implications for clinical decision-making. Diseases of the esophagus : official journal of the International Society for Diseases of the Esophagus Triadafilopoulos, G., Kamal, A., Zikos, T., Nguyen, L., Clarke, J. O. 2020


    Although High resolution esophageal manometry (HRM) is the gold standard to assess esophageal motility, little is known about the stability of the manometric diagnosis over time and its implications for management. To assess the stability and usefulness of repeat HRM in patients presenting with esophageal symptoms over time we performed this retrospective study of patients with esophageal symptoms. Medical records, questionnaires, and HRM tracing were independently reviewed using the Chicago classification. The primary objective was to assess the stability of the manometric diagnosis over time; secondary objective was its change (positive or negative). At least one repeat study was performed in 86 patients (36% women, ages 20-86, with mild to moderate symptoms), while 26 had a third procedure. Mean intervals between studies were 15±1.6months (for baseline v. first study) and 13±0.8months (for second to third study). Of the 27 patients initially with a normal study, 11 changed (five had esophago-gastric junction outflow obstruction [EGJOO], two diffuse esophageal spasm [DES], one jackhammer esophagus [JE], and three ineffective esophageal motility [IEM] [41% change]). Of the 24 patients with initial EGJOO, only nine retained it (65.2% change). Of nine patients with initial DES, four changed (44.4% change). Similarly, different diagnosis was seen in 7 of 24 initial IEM patients (22.7% change). Only one patient had achalasia initially and this remained stable. Additional changes were noted on a third HRM. Fluidity in the HRM diagnosis over time questions its validity at any timepoint and raises doubts about the need for intervention.

    View details for DOI 10.1093/dote/doz094

    View details for PubMedID 31909786

  • Development of a Preliminary Question Prompt List as a Communication Tool for Adults With Gastroesophageal Reflux Disease: A Modified Delphi Study. Journal of clinical gastroenterology Kamal, A. n., Katzka, D. A., Achkar, E. n., Carlson, D. n., Clarke, J. n., Fass, R. n., Gyawali, C. P., Patel, D. n., Penagini, R. n., Rezaie, A. n., Roman, S. n., Savarino, E. n., Shaheen, N. J., Triadafilopoulos, G. n. 2020


    Question prompt lists (QPLs) are structured sets of disease-specific questions intended for patient use, encouraging patients to ask questions to facilitate their consultation with their physician.The aim of this study was to develop a QPL specific to adults with gastroesophageal reflux disease (GERD), created by esophageal experts.The QPL content (78 questions) was derived through a modified Delphi method consisting of 2 rounds. In round 1, 18 esophageal experts provided 5 answers to the prompt "What you wish your patients would ask" and "What questions do patients often not ask, that I wish they would ask?" In round 2, the experts rated each question on a 5-point Likert scale, and responses rated as "essential" or "important," determined by an a priori threshold of ≥4.0, were accepted for the QPL.Twelve esophageal experts participated. Of 143 questions from round 1, 110 (76.9%) were accepted for inclusion in the QPL, meeting a median value of ≥4.0, and, subsequently, it reduced to 78, minimizing redundancy. Median values ranged between 4.0 and 5.0, with the highest agreement median (5.0) for questions asking dosing and timing of proton pump inhibitor therapy, and surveillance in Barrett's. Questions were categorized into the following categories: "What does this illness mean," "lifestyle modifications," "general treatment," "treatment with proton pump inhibitors," "What I should expect for my future," and "Barrett's." The largest number of questions covered lifestyle modifications (21.8%), with the highest agreement median (5.0) for "How helpful are lifestyle modifications in GERD?"A preliminary GERD-specific QPL, the first of its kind, was developed by esophageal experts. Modification after more patient consultation and feedback is planned in subsequent versions to create a GERD-QPL for eventual use in clinical gastroenterology.

    View details for DOI 10.1097/MCG.0000000000001300

    View details for PubMedID 31985713

  • Building an integrated multidisciplinary swallowing disorder clinic: considerations, challenges, and opportunities. Annals of the New York Academy of Sciences Starmer, H. M., Dewan, K. n., Kamal, A. n., Khan, A. n., Maclean, J. n., Randall, D. R. 2020


    Dysphagia is a complex condition with numerous causes, symptoms, and treatments. As such, patients with dysphagia commonly require a multidisciplinary approach to their evaluation and treatment. Integrated multidisciplinary clinics provide an optimal format for a collaborative approach to patient care. In this manuscript, we will discuss considerations for teams looking to build a multidisciplinary dysphagia clinic, including what professionals are typically involved, what patients benefit most from this approach, what tests are most appropriate for which symptoms, financial issues, and traversing interpersonal challenges.

    View details for DOI 10.1111/nyas.14435

    View details for PubMedID 32686095

  • The functional lumen imaging probe in gastrointestinal disorders: the past, present, and future. Annals of the New York Academy of Sciences Clarke, J. O., Ahuja, N. K., Fernandez-Becker, N. Q., Gregersen, H. n., Kamal, A. N., Khan, A. n., Lynch, K. L., Vela, M. F. 2020


    The functional lumen imaging probe (FLIP) is a diagnostic tool that utilizes impedance planimetry to allow the assessment of luminal diameter and distensibility. It has been used primarily in esophageal diseases, in particular, in the assessment of achalasia, esophagogastric junction outflow obstruction, and eosinophilic esophagitis (EoE). The usage and publications have increased over the past decade and it is now an essential tool in the armamentarium of the esophagologist. Indications are emerging outside of the esophagus, in particular with regard to gastroparesis. Our paper will review the history of FLIP, optimal current usage, data for key esophageal disorders (including achalasia, reflux, and EoE), data for nonesophageal disorders, and our sense as to whether FLIP is ready for prime time, as well as gaps in evidence and suggestions for future research.

    View details for DOI 10.1111/nyas.14463

    View details for PubMedID 32814368

  • Diagnosis of gastroesophageal reflux: an update on current and emerging modalities. Annals of the New York Academy of Sciences Ang, D. n., Lee, Y. Y., Clarke, J. O., Lynch, K. n., Guillaume, A. n., Onyimba, F. n., Kamal, A. n., Gyawali, C. P. 2020


    Gastroesophageal reflux disease (GERD) is a common condition characterized by troublesome symptoms or esophageal mucosal lesions attributed to excessive esophageal acid exposure. Various pathophysiological mechanisms account for GERD, including impaired esophageal peristalsis and anatomical or physiological defects at the esophagogastric junction (EGJ). Endoscopy identifies GERD complications and detects potential alternative diagnoses. However, if symptoms persist despite proton pump inhibitor therapy, functional esophageal tests are useful to characterize reflux burden and define the symptom association profile. Ambulatory pH or pH-impedance monitoring measures the 24-h acid exposure time, which remains the most reproducible reflux metric and predicts response to antireflux therapy. Apart from identifying peristaltic dysfunction, esophageal high-resolution manometry defines the morphology and contractile vigor (EGJ-CI) of the EGJ. Novel metrics obtained from pH-impedance monitoring include the postreflux swallow-induced peristaltic wave index and mean nocturnal baseline impedance, which augment the diagnostic value of pH-impedance testing. Mucosal impedance can also be recorded using a probe inserted through a gastroscope, or a novel balloon catheter with arrays of impedance electrodes inserted following sedated endoscopy. The latest developments in functional esophageal tests define the GERD phenotype based on pathogenesis, reflux exposure, structural or motility disorders, and symptom burden, facilitating appropriate treatment.

    View details for DOI 10.1111/nyas.14369

    View details for PubMedID 32428279

  • Baseline impedance via manometry and ambulatory reflux testing are not equivalent when utilized in the evaluation of potential extra-esophageal gastroesophageal reflux disease. Journal of thoracic disease Zikos, T. A., Triadafilopoulos, G. n., Kamal, A. n., Podboy, A. n., Sonu, I. S., Regalia, K. A., Nandwani, M. C., Nguyen, L. A., Fernandez-Becker, N. Q., Clarke, J. O. 2020; 12 (10): 5628–38


    Esophageal baseline impedance (BI) shows promise for the diagnosis of gastroesophageal reflux disease (GERD), but means of acquisition and relevance to extra-esophageal manifestations of GERD (EE-GERD) remain unclear. In this study we aim to (I) evaluate concordance between BI as measured by 24-hour pH-impedance (pH-MII) and high-resolution impedance manometry (HRIM), and (II) assess relationship to potential EE-GERD symptoms.In this prospective open cohort study, patients presenting for outpatient HRIM and pH-MII studies were prospectively enrolled. All patients completed the GERD-HRQL, NOSE, and respiratory symptom index questionnaire (RSI), plus questions regarding wheezing and dental procedures. HRIM and pH-MII were evaluated with calculation of BI. Correlations were assessed using either Pearson's correlation or Spearman's rank coefficients.70 HRIM patients were enrolled, 35 of whom underwent pH-MII. There was no correlation between BI measurements as assessed by HRIM and pH-MII proximally, but there was moderate-weak correlation distally (r=0.34 to 0.5). Distal acid exposure time correlated with distal BI only for measurements by pH-MII (rho= -0.5 to -0.65), and not by HRIM. There was no relationship between proximal acid exposure time and proximal BI. There were no correlations when comparing proximal or distal BI measurements, acid exposure times, and impedance events to symptoms.Concordance between BI as measured by HRIM and pH-MII is poor, especially proximally, suggesting that these two methods are not interchangeable. There is no correlation between BI both distally/proximally and symptoms of either GERD/EE-GERD, suggesting that many symptoms are unrelated to acid or that BI is not an adequate marker to assess EE-GERD symptoms.

    View details for DOI 10.21037/jtd-20-1623

    View details for PubMedID 33209395

    View details for PubMedCentralID PMC7656325

  • Reflux Hypersensitivity: How to Approach Diagnosis and Management. Current gastroenterology reports Aggarwal, P. n., Kamal, A. N. 2020; 22 (9): 42


    This paper aims to review the definition and diagnostic criteria for reflux hypersensitivity and comment on the present and future management of this condition.In 2016, the Rome IV criteria redefined reflux hypersensitivity as characterized by typical reflux symptoms, absence of endoscopic mucosal disease, absence of pathologic gastroesophageal reflux, and positive symptom correlation between reflux and heartburn episodes. Though uncertain, TPRV1 receptors have been implicated in the pathophysiology of reflux hypersensitivity. Recent studies have shown neuromodulators like SSRIs, SNRIs, and TCAs may be the future of managing this condition. With the release of the Rome IV criteria and availability of continuous pH monitoring, the diagnosis of reflux hypersensitivity has become more streamlined. Though there is no definitive therapy for reflux hypersensitivity, several anti-secretory agents and neuromodulators have shown some efficacy in therapeutic trials. The lack of large-scale, randomized controlled trials, however, reinforces the need for further research into the pharmacotherapy of reflux hypersensitivity.

    View details for DOI 10.1007/s11894-020-00779-x

    View details for PubMedID 32651667

  • The Association Between Gastroparesis and Slow Transit Constipation as Seen by Wireless Motility Capsule (WMC) Radetic, M., Kamal, A., Rouphael, C., Cline, M. LIPPINCOTT WILLIAMS & WILKINS. 2019: S692–S693
  • Gastric per-oral endoscopic myotomy: Current status and future directions WORLD JOURNAL OF GASTROENTEROLOGY Podboy, A., Hwang, J., Nguyen, L. A., Garcia, P., Zikos, T. A., Kamal, A., Triadafilopoulos, G., Clarke, J. O. 2019; 25 (21): 2581–90
  • Gastric per-oral endoscopic myotomy: Current status and future directions. World journal of gastroenterology Podboy, A., Hwang, J. H., Nguyen, L. A., Garcia, P., Zikos, T. A., Kamal, A., Triadafilopoulos, G., Clarke, J. O. 2019; 25 (21): 2581-2590


    Gastroparesis, or symptomatic delayed gastric emptying in the absence of mechanical obstruction, is a challenging and increasingly identified syndrome. Medical options are limited and the only medication approved by the Food and Drug Administration for treatment of gastroparesis is metoclopramide, although other agents are frequently used off label. With this caveat, first-line treatments for gastroparesis include dietary modifications, antiemetics and promotility agents, although these therapies are limited by suboptimal efficacy and significant medication side effects. Treatment of patients that fail first-line treatments represents a significant therapeutic challenge. Recent advances in endoscopic techniques have led to the development of a promising novel endoscopic therapy for gastroparesis via endoscopic pyloromyotomy, also referred to as gastric per-oral endoscopic myotomy or per-oral endoscopic pyloromyotomy. The aim of this article is to review the technical aspects of the per-oral endoscopic myotomy procedure for the treatment of gastroparesis, provide an overview of the currently published literature, and outline potential next directions for the field.

    View details for DOI 10.3748/wjg.v25.i21.2581

    View details for PubMedID 31210711

    View details for PubMedCentralID PMC6558440

  • Under Pressure: Do Volume-Based Measurements Define Rectal Hyposensitivity in Clinical Practice? DIGESTIVE DISEASES AND SCIENCES Kamal, A. N., Garcia, P., Clarke, J. O. 2019; 64 (5): 1062–63
  • Under Pressure: Do Volume-Based Measurements Define Rectal Hyposensitivity in Clinical Practice? Digestive diseases and sciences Kamal, A. N., Garcia, P., Clarke, J. O. 2019

    View details for PubMedID 30963367

  • High Prevalence of Slow Transit Constipation in Patients With Gastroparesis JOURNAL OF NEUROGASTROENTEROLOGY AND MOTILITY Zikos, T. A., Kamal, A. N., Neshatian, L., Triadafilopoulos, G., Clarke, J. O., Nandwani, M., Nguyen, L. A. 2019; 25 (2): 267–75

    View details for DOI 10.5056/jnm18206

    View details for Web of Science ID 000464525700012

  • High Prevalence of Slow Transit Constipation in Patients With Gastroparesis. Journal of neurogastroenterology and motility Zikos, T. A., Kamal, A. N., Neshatian, L., Triadafilopoulos, G., Clarke, J. O., Nandwani, M., Nguyen, L. A. 2019


    Background/Aims: Current evidence suggests the presence of motility or functional abnormalities in one area of the gastrointestinal tract increases the likelihood of abnormalities in others. However, the relationship of gastroparesis to chronic constipation (slow transit constipation and dyssynergic defecation) has been incompletely evaluated.Methods: We retrospectively reviewed the records of all patients with chronic dyspeptic symptoms and constipation who underwent both a solid gastric emptying scintigraphy and a highresolution anorectal manometry at our institution since January 2012. When available, Xray defecography and radiopaque marker colonic transit studies were also reviewed. Based on the gastric emptying results, patients were classified as gastroparesis or dyspepsia with normal gastric emptying (control group). Differences in anorectal and colonic findings were then compared between groups.Results: Two hundred and six patients met the inclusion criteria. Patients with gastroparesis had higher prevalence of slow transit constipation by radiopaque marker study compared to those with normal emptying (64.7% vs 28.1%, P = 0.013). Additionally, patients with gastroparesis had higher rates of rectocele (88.9% vs 60.0%, P = 0.008) and intussusception (44.4% vs 12.0%, P = 0.001) compared to patients with normal emptying. There was no difference in the rate of dyssynergic defecation between those with gastroparesis vs normal emptying (41.1% vs 42.1%, P = 0.880), and no differences in anorectal manometry findings.Conclusions: Patients with gastroparesis had a higher rate of slow transit constipation, but equal rates of dyssynergic defecation compared to patients with normal gastric emptying. These findings argue for investigation of possible delayed colonic transit in patients with gastroparesis and vice versa.

    View details for PubMedID 30870880

  • Inflammatory Bowel Disease and Irritable Bowel Syndrome: What to Do When There Is an Overlap INFLAMMATORY BOWEL DISEASES Kamal, A., Padival, R., Lashner, B. 2018; 24 (12): 2479–82

    View details for DOI 10.1093/ibd/izy277

    View details for Web of Science ID 000456677100001

    View details for PubMedID 30169572