Clinical Focus


  • Gastroenterology

Academic Appointments


Professional Education


  • Board Certification: American Board of Internal Medicine, Internal Medicine (2014)
  • Fellowship: Mayo Clinic Gastroenterology Fellowship (2019) MN
  • Board Certification: American Board of Internal Medicine, Gastroenterology (2018)
  • Fellowship: Mayo Clinic Gastroenterology Fellowship (2018) MN
  • Residency: Indiana University Internal Medicine Residency (2014) IN
  • Medical Education: American University of Beirut Office of the Registrar (2009) Lebanon

Clinical Trials


  • Extension Study to PTR-01-002 (A Study in Recessive Dystrophic Epidermolysis Bullosa (RDEB) Patients Previously Treated With PTR-01) Not Recruiting

    A sub-set of patients who participated in PTR-01-002 will be enrolled in an open-label study, if they meet the study eligibility criteria.

    Stanford is currently not accepting patients for this trial. For more information, please contact Irene Bailey, 650-721-7149.

    View full details

All Publications


  • Anorectal manometry for the diagnosis of pelvic floor disorders in patients with hypermobility spectrum disorders and hypermobile Ehlers-Danlos syndrome. BMC gastroenterology Zhou, W., Zikos, T. A., Halawi, H., Sheth, V. R., Gurland, B., Nguyen, L. A., Neshatian, L. 2022; 22 (1): 538

    Abstract

    INTRODUCTION: Functional gastrointestinal disorders (FGID) including impaired rectal evacuation are common in patients with Hypermobility Spectrum Disorder (HSD) or Hypermobile Ehlers-Danlos Syndrome (hEDS). The effect of connective tissue pathologies on pelvic floor function in HSD/hEDS remains unclear. We aimed to compare clinical characteristics and anorectal pressure profile in patients with HSD/hEDS to those of age and sex matched controls.METHODS: We conducted a retrospective review of all FGID patients who underwent high resolution anorectal manometry (HR-ARM) and balloon expulsion test (BET) for evaluation of impaired rectal evacuation. Patients with HSD/hEDS were age and sex matched to a randomly selected cohort of control patients without HSD/hEDS. An abnormal BET was defined as the inability to expel a rectal balloon within 2minutes. Wilcoxon rank sum test and Fisher's exact test were used to make comparisons and logistic regression model for predictive factors for abnormal evacuation.RESULTS: A total of 144 patients (72 with HSD/hEDS and 72 controls) were analyzed. HSD/hEDS patients were more likely to be Caucasian (p<0.001) and nulliparous. Concurrent psychiatric disorders; depression, and anxiety (p<0.05), and somatic syndromes; fibromyalgia, migraine and sleep disorders (p<0.001) were more common in these patients. Rate of abnormal BET were comparable among the groups. HDS/hEDS patients had significantly less anal relaxation and higher residual anal pressures during simulated defecation, resulting in significantly more negative rectoanal pressure gradient. The remaining anorectal pressure profile and sensory levels were comparable between the groups. While diminished rectoanal pressure gradient was the determinant of abnormal balloon evacuation in non HSD/hEDS patients, increased anal resting tone and maximum volume tolerated were independent factors associated with an abnormal BET in HSD/hEDS patients. Review of defecography data from a subset of patients showed no significant differences in structural pathologies between HSD/hEDS and non HSD/hEDS patients.CONCLUSIONS: These results suggest anorectal pressure profile is not compromised by connective tissue pathologies in HSD patients. Whether concurrent psychosomatic disorders or musculoskeletal involvement impact the pelvic floor function in these patients needs further investigation.

    View details for DOI 10.1186/s12876-022-02572-8

    View details for PubMedID 36564719

  • Diagnostic journeys: characterization of patients and diagnostic outcomes from an academic second opinion clinic. Diagnosis (Berlin, Germany) Chao, S., Lotfi, J., Lin, B., Shaw, J., Jhandi, S., Mahoney, M., Singh, B., Nguyen, L., Halawi, H., Geng, L. N. 2022

    Abstract

    Diagnostic programs and second opinion clinics have grown and evolved in the recent years to help patients with rare, puzzling, and complex conditions who often suffer prolonged diagnostic journeys, but there is a paucity of literature on the clinical characteristics of these patients and the efficacy of these diagnostic programs. This study aims to characterize the diagnostic journey, case features, and diagnostic outcomes of patients referred to a team-based second opinion clinic at Stanford.Retrospective chart review was performed for 237 patients evaluated for diagnostic second opinion in the Stanford Consultative Medicine Clinic over a 5 year period. Descriptive case features and diagnostic outcomes were assessed, and correlation between the two was analyzed.Sixty-three percent of our patients were women. 49% of patients had a potential precipitating event within about a month prior to the start of their illness, such as medication change, infection, or medical procedure. A single clear diagnosis was determined in 33% of cases, whereas the remaining cases were assessed to have multifactorial contributors/diagnoses (20%) or remained unclear despite extensive evaluation (47%). Shorter duration of illness, fewer prior specialties seen, and single chief symptom were associated with higher likelihood of achieving a single clear diagnosis.A single-site academic consultative service can offer additional diagnostic insights for about half of all patients evaluated for puzzling conditions. Better understanding of the clinical patterns and patient experiences gained from this study helps inform strategies to shorten their diagnostic odysseys.

    View details for DOI 10.1515/dx-2022-0029

    View details for PubMedID 35596123