Clinical Focus


  • Internal Medicine
  • Critical Care Medicine

Academic Appointments


Honors & Awards


  • Alpha Omega Alpha, Temple University School of Medicine (2018)

Professional Education


  • Fellowship: Stanford University Critical Care Medicine Fellowship (2024) CA
  • Board Certification: American Board of Internal Medicine, Pulmonary Disease (2023)
  • Board Certification: American Board of Internal Medicine, Internal Medicine (2021)
  • Residency: Stanford Health Care (2021) CA
  • Medical Education: Temple University (2018) PA
  • BS, Santa Clara University, Finance, Psychology (2011)
  • MD, Temple University School of Medicine (2018)

Stanford Advisors


Graduate and Fellowship Programs


  • Pulmonary & Critical Care Medicine (Fellowship Program)

All Publications


  • Sex differences and immune correlates of Long COVID development, persistence, and resolution. bioRxiv : the preprint server for biology Hamlin, R. E., Pienkos, S. M., Chan, L., Stabile, M. A., Pinedo, K., Rao, M., Grant, P., Bonilla, H., Holubar, M., Singh, U., Jacobson, K. B., Jagannathan, P., Maldonado, Y., Holmes, S. P., Subramanian, A., Blish, C. A. 2024

    Abstract

    Sex differences have been observed in acute COVID-19 and Long COVID (LC) outcomes, with greater disease severity and mortality during acute infection in males and a greater proportion of females developing LC. We hypothesized that sex-specific immune dysregulation contributes to the pathogenesis of LC. To investigate the immunologic underpinnings of LC development and persistence, we used single-cell transcriptomics, single-cell proteomics, and plasma proteomics on blood samples obtained during acute SARS-CoV-2 infection and at 3 and 12 months post-infection in a cohort of 45 patients who either developed LC or recovered. Several sex-specific immune pathways were associated with LC. Specifically, males who would develop LC at 3 months had widespread increases in TGF-β signaling during acute infection in proliferating NK cells. Females who would develop LC demonstrated increased expression of XIST, an RNA gene implicated in autoimmunity, and increased IL1 signaling in monocytes at 12 months post infection. Several immune features of LC were also conserved across sexes. Both males and females with LC had reduced co-stimulatory signaling from monocytes and broad upregulation of NF-κB transcription factors. In both sexes, those with persistent LC demonstrated increased LAG3, a marker of T cell exhaustion, reduced ETS1 transcription factor expression across lymphocyte subsets, and elevated intracellular IL-4 levels in T cell subsets, suggesting that ETS1 alterations may drive an aberrantly elevated Th2-like response in LC. Altogether, this study describes multiple innate and adaptive immune correlates of LC, some of which differ by sex, and offers insights toward the pursuit of tailored therapeutics.

    View details for DOI 10.1101/2024.06.18.599612

    View details for PubMedID 38948732

    View details for PubMedCentralID PMC11212991

  • Association between emergency department disposition and mortality in patients with COVID-19 acute respiratory distress syndrome. Journal of the American College of Emergency Physicians open Lebold, K. M., Moore, A. R., Sanchez, P. A., Pacheco-Navarro, A. E., O'Donnell, C., Roque, J., Parmer, C., Pienkos, S., Levitt, J., Collins, W. J., Rogers, A. J., Wilson, J. G. 2024; 5 (3): e13192

    Abstract

    Patients hospitalized for COVID-19 frequently develop hypoxemia and acute respiratory distress syndrome (ARDS) after admission. In non-COVID-19 ARDS studies, admission to hospital wards with subsequent transfer to intensive care unit (ICU) is associated with worse outcomes. We hypothesized that initial admission to the ward may affect outcomes in patient with COVID-19 ARDS.This was a retrospective study of consecutive adults admitted for COVID-19 ARDS between March 2020 and March 2021 at Stanford Health Care. Mortality scores at hospital admission (Coronavirus Clinical Characterization Consortium Mortality Score [4C score]) and ICU admission (Simplified Acute Physiology Score III [SAPS-III]) were calculated, as well as ROX index for patients on high flow nasal oxygen. Patients were classified by emergency department (ED) disposition (ward-first vs. ICU-direct), and 28- and 60-day mortality and highest level of respiratory support within 1 day of ICU admission were compared. A second cohort (April 2021‒July 2022, n = 129) was phenotyped to validate mortality outcome.A total of 157 patients were included, 48% of whom were first admitted to the ward (n = 75). Ward-first patients had more comorbidities, including lung disease. Ward-first patients had lower 4C and similar SAPS-III score, yet increased mortality at 28 days (32% vs. 17%, hazard ratio [HR] 2.0, 95% confidence interval [95% CI] 1.0‒3.7, p = 0.039) and 60 days (39% vs. 23%, HR 1.83, 95% CI 1.04‒3.22, p = 0.037) compared to ICU-direct patients. More ward-first patients escalated to mechanical ventilation on day 1 of ICU admission (36% vs. 14%, p = 0.002) despite similar ROX index. Ward-first patients who upgraded to ICU within 48 h of ED presentation had the highest mortality. Mortality findings were replicated in a sensitivity analysis.Despite similar baseline risk scores, ward-first patients with COVID-19 ARDS had increased mortality and escalation to mechanical ventilation compared to ICU-direct patients. Ward-first patients requiring ICU upgrade within 48 h were at highest risk, highlighting a need for improved identification of this group at ED admission.

    View details for DOI 10.1002/emp2.13192

    View details for PubMedID 38887225

    View details for PubMedCentralID PMC11180691

  • Elevated Plasma Interleukin-18 Identifies High-Risk Acute Respiratory Distress Syndrome Patients not Distinguished by Prior Latent Class Analyses Using Traditional Inflammatory Cytokines: A Retrospective Analysis of Two Randomized Clinical Trials. Critical care medicine Moore, A. R., Pienkos, S. M., Sinha, P., Guan, J., O'Kane, C. M., Levitt, J. E., Wilson, J. G., Shankar-Hari, M., Matthay, M. A., Calfee, C. S., Baron, R. M., McAuley, D. F., Rogers, A. J. 2023

    Abstract

    Interleukin-18 (IL-18) plasma level and latent class analysis (LCA) have separately been shown to predict prognosis and treatment response in acute respiratory distress syndrome (ARDS). IL-18 is a measure of inflammasome activation, a pathway potentially distinct from inflammation captured by biomarkers defining previously published LCA classes. We hypothesized that elevated IL-18 would identify distinct "high-risk" patients not captured by prior LCA classifications.Statins for acutely injured lungs from sepsis (SAILS) and hydroxymethylglutaryl-CoA reductase inhibition with simvastatin in acute lung injury to reduce pulmonary dysfunction trial (HARP-2) are two large randomized, controlled trials in ARDS in which both LCA assignments and IL-18 levels were shown to predict mortality. We first evaluated the overlap between high IL-18 levels (≥ 800 pg/mL) with prior LCA class assignments using McNemar's test and then tested the correlation between IL-18 and LCA biomarkers using Pearson's exact test on log-2 transformed values. Our primary analysis was the association of IL-18 level with 60-day mortality in the hypoinflammatory LCA class, which was assessed using the Fisher exact test and Cox proportional hazards modeling adjusting for age, Acute Physiology and Chronic Health Evaluation score, and gender. Secondary analyses included the association of IL-18 and LCA with mortality within each IL-18/LCA subgroup.Secondary analysis of two multicenter, randomized controlled clinical trials of ARDS patients.Six hundred eighty-three patients in SAILS and 511 patients in HARP-2.None.We found that 33% of patients in SAILS and HARP-2 were discordant by IL-18 level and LCA class. We further found that IL-18 level was only modestly correlated (0.17-0.47) with cytokines used in the LCA assignment. A substantial subset of individuals classified as hypoinflammatory by LCA (14% of SAILS and 43% of HARP-2) were classified as high risk by elevated IL-18. These individuals were at high risk for mortality in both SAILS (42% 60-d mortality, odds ratio [OR] 3.3; 95% CI, 1.8-6.1; p < 0.001) and HARP-2 (27% 60-d mortality, OR 2.1; 95% CI, 1.2-3.8; p = 0.009).Plasma IL-18 level provides important additional prognostic information to LCA subphenotypes defined largely by traditional inflammatory biomarkers in two large ARDS cohorts.

    View details for DOI 10.1097/CCM.0000000000006028

    View details for PubMedID 37695136

  • Right Ventricular Dysfunction Patterns Among Patients with COVID-19 in the Intensive Care Unit - a Retrospective Cohort Analysis. Annals of the American Thoracic Society Sanchez, P. A., O'Donnell, C. T., Francisco, N., Santana, E. J., Moore, A. R., Pacheco-Navarro, A., Roque, J., Lebold, K. M., Parmer, C. M., Pienkos, S. M., Celestin, B. E., Levitt, J. E., Collins, W. J., Lanspa, M. J., Ashley, E. A., Wilson, J. G., Haddad, F., Rogers, A. J. 2023

    Abstract

    Right ventricular (RV) dysfunction is common among patients hospitalized with COVID-19; however, its epidemiology may depend on the echocardiographic parameters used to define it.To evaluate the prevalence of abnormalities in three common echocardiographic parameters of RV function among COVID-19 patients admitted to the intensive care unit, as well as the effect of RV dilatation on differential parameter abnormality and the association of RV dysfunction with 60-day mortality.Retrospective cohort study of COVID-19 ICU patients between March 4th,2020 to March 4th, 2021, who received a transthoracic echocardiogram within 48 hours before to at most 7 days after ICU admission. RV dysfunction and dilatation respectively defined by guideline thresholds for tricuspid annular plane systolic excursion (TAPSE), RV fractional area change (RVFAC), RV free wall longitudinal strain (RVFWS), and RV basal dimension or RV end-diastolic area. Association of RV dysfunction with 60-day mortality assessed through logistic regression adjusting for age, prior history of congestive heart failure, invasive ventilation at time of TTE and APACHE II score.116 patients were included, of which 69% had RV dysfunction by > 1 parameter and 36.3% of these had RV dilatation. The three most common patterns of RV dysfunction included: Presence of 3 abnormalities, the combination of abnormal RVFWS and TAPSE, and isolated TAPSE abnormality. Patients with RV dilatation had worse RVFAC (24% vs 36%, p = 0.001), worse RVFWS (16.3% vs 19.1%, p = 0.005), higher RVSP (45mmHg vs 31mmHg, p = 0.001) but similar TAPSE (13mm vs 13mm, p = 0.30) compared to those with normal RV size. After multivariable adjustment, 60-day mortality was significantly associated with RV dysfunction (OR 2.91, 95% CI 1.01 - 9.44), as was the presence of at least 2 parameter abnormalities.ICU patients with COVID-19 had significant heterogeneity in RV function abnormalities present with different patterns associated with RV dilatation. RV dysfunction by any parameter was associated with increased mortality. Therefore, a multiparameter evaluation may be critical in recognizing RV dysfunction in COVID-19.

    View details for DOI 10.1513/AnnalsATS.202303-235OC

    View details for PubMedID 37478340

  • Effect of total cholesterol and statin therapy on mortality in ARDS patients: a secondary analysis of the SAILS and HARP-2 trials. Critical care (London, England) Pienkos, S. M., Moore, A. R., Guan, J., Levitt, J. E., Matthay, M. A., Baron, R. M., Conlon, J., McAuley, D. F., O'Kane, C. M., Rogers, A. J. 2023; 27 (1): 126

    Abstract

    Two acute respiratory distress syndrome (ARDS) trials showed no benefit for statin therapy, though secondary analyses suggest inflammatory subphenotypes may have a differential response to simvastatin. Statin medications decrease cholesterol levels, and low cholesterol has been associated with increased mortality in critical illness. We hypothesized that patients with ARDS and sepsis with low cholesterol could be harmed by statins.Secondary analysis of patients with ARDS and sepsis from two multicenter trials. We measured total cholesterol from frozen plasma samples obtained at enrollment in Statins for Acutely Injured Lungs from Sepsis (SAILS) and Simvastatin in the Acute Respiratory Distress Syndrome (HARP-2) trials, which randomized subjects with ARDS to rosuvastatin versus placebo and simvastatin versus placebo, respectively, for up to 28 days. We compared the lowest cholesterol quartile (< 69 mg/dL in SAILS, < 44 mg/dL in HARP-2) versus all other quartiles for association with 60-day mortality and medication effect. Fisher's exact test, logistic regression, and Cox Proportional Hazards were used to assess mortality.There were 678 subjects with cholesterol measured in SAILS and 509 subjects in HARP-2, of whom 384 had sepsis. Median cholesterol at enrollment was 97 mg/dL in both SAILS and HARP-2. Low cholesterol was associated with higher APACHE III and shock prevalence in SAILS, and higher Sequential Organ Failure Assessment score and vasopressor use in HARP-2. Importantly, the effect of statins differed in these trials. In SAILS, patients with low cholesterol who received rosuvastatin were more likely to die (odds ratio (OR) 2.23, 95% confidence interval (95% CI) 1.06-4.77, p = 0.02; interaction p = 0.02). In contrast, in HARP-2, low cholesterol patients had lower mortality if randomized to simvastatin, though this did not reach statistical significance in the smaller cohort (OR 0.44, 95% CI 0.17-1.07, p = 0.06; interaction p = 0.22).Cholesterol levels are low in two cohorts with sepsis-related ARDS, and those in the lowest cholesterol quartile are sicker. Despite the very low levels of cholesterol, simvastatin therapy seems safe and may reduce mortality in this group, though rosuvastatin was associated with harm.

    View details for DOI 10.1186/s13054-023-04387-9

    View details for PubMedID 36978134

    View details for PubMedCentralID 6201750

  • Novel TRAF2 variant and KDR deletion are implicated in the pathogenesis of pulmonary arterial hypertension Gallego, N., Pienkos, S., Condon, D., Cruz, A., Ochoa, N., Nevado, J., Arias, P., Agarwal, S., Patel, H., Chakraborty, A., Lapunzina, P., Escribano, P., de Jesus, V., Tenorio, J. SPRINGERNATURE. 2022: 197-198
  • Novel TNIP2 and TRAF2 Variants Are Implicated in the Pathogenesis of Pulmonary Arterial Hypertension FRONTIERS IN MEDICINE Pienkos, S., Gallego, N., Condon, D. F., Cruz-Utrilla, A., Ochoa, N., Nevado, J., Arias, P., Agarwal, S., Patel, H., Chakraborty, A., Lapunzina, P., Escribano, P., Tenorio-Castano, J., de Jesus Perez, V. A., Spanish PAH Consortium 2021; 8: 625763

    Abstract

    Background: Pulmonary arterial hypertension (PAH) is a rare disease characterized by pulmonary vascular remodeling and right heart failure. Specific genetic variants increase the incidence of PAH in carriers with a family history of PAH, those who suffer from certain medical conditions, and even those with no apparent risk factors. Inflammation and immune dysregulation are related to vascular remodeling in PAH, but whether genetic susceptibility modifies the PAH immune response is unclear. TNIP2 and TRAF2 encode for immunomodulatory proteins that regulate NF-κB activation, a transcription factor complex associated with inflammation and vascular remodeling in PAH. Methods: Two unrelated families with PAH cases underwent whole-exome sequencing (WES). A custom pipeline for variant prioritization was carried out to obtain candidate variants. To determine the impact of TNIP2 and TRAF2 in cell proliferation, we performed an MTS [3-(4,5-dimethylthiazol-2-yl)-5-(3-carboxymethoxyphenyl)-2-(4-sulfophenyl)-2H-tetrazolium] assay on healthy lung pericytes transfected with siRNA specific for each gene. To measure the effect of loss of TNIP2 and TRAF2 on NF-kappa-beta (NF-κB) activity, we measured levels of Phospho-p65-NF-κB in siRNA-transfected pericytes using western immunoblotting. Results: We discovered a novel missense variant in the TNIP2 gene in two affected individuals from the same family. The two patients had a complex form of PAH with interatrial communication and scleroderma. In the second family, WES of the proband with PAH and primary biliary cirrhosis revealed a de novo protein-truncating variant in the TRAF2. The knockdown of TNIP2 and TRAF2 increased NF-κB activity in healthy lung pericytes, which correlated with a significant increase in proliferation over 24 h. Conclusions: We have identified two rare novel variants in TNIP2 and TRAF2 using WES. We speculate that loss of function in these genes promotes pulmonary vascular remodeling by allowing overactivation of the NF-κB signaling activity. Our findings support a role for WES in helping identify novel genetic variants associated with dysfunctional immune response in PAH.

    View details for DOI 10.3389/fmed.2021.625763

    View details for Web of Science ID 000649921700001

    View details for PubMedID 33996849

    View details for PubMedCentralID PMC8119639

  • Pulmonary Arterial Hypertension Secondary to Drugs and Toxins. Clinics in chest medicine Ramirez, R. L., Pienkos, S. M., de Jesus Perez, V., Zamanian, R. T. 2021; 42 (1): 19–38

    Abstract

    Pulmonary arterial hypertension secondary to drugs and toxins is an important subgroup of group 1 pulmonary hypertension associated with significant morbidity and mortality. Many drugs and toxins have emerged as risk factors for pulmonary arterial hypertension, which include anorexigens, illicit agents, and several US Food and Drug Administration-approved therapeutic medications. Drugs and toxins are classified as possible or definite risk factors for pulmonary arterial hypertension. This article reviews agents that have been implicated in the development of pulmonary arterial hypertension, their pathologic mechanisms, and methods to prevent the next deadly outbreak of drug- and toxin-induced pulmonary arterial hypertension.

    View details for DOI 10.1016/j.ccm.2020.11.008

    View details for PubMedID 33541612

  • The chronic disease self-management program--A pilot study in patients undergoing hemodialysis. Nephrology news & issues Slesnick, N., Pienkos, S., Sun, S., Doss-McQuitty, S., Schiller, B. 2015; 29 (4): 22-3, 27-8, 30-2

    Abstract

    A strong emphasis on self-management for health maintenance in a variety of chronic diseases has been shown to benefit patients' outcomes and quality of life. However, little has been published on such programs in patients with chronic kidney disease. We studied the feasibility and effectiveness of the Chronic Disease Self-Management Program (CDSMP) in 14 patients with ESRD undergoing conventional hemodialysis. This program is designed to enhance skills in the areas of medical, emotional, and role management. Outcome measures in health status, self-management behaviors, self-efficacy, and health care utilization were evaluated through use of questionnaires at baseline and after six months.

    View details for PubMedID 26263750

  • Knowledge and perception of home dialysis in ESRD patients: a survey in incident and prevalent patients undergoing in-center HD. Nephrology news & issues Pienkos, S., Sun, S., Doss-McQuitty, S., Czajkowski, T., Schiller, B. 2013; 27 (6): 24-6, 28

    View details for PubMedID 23729080

  • First exposure to home therapy options--where, when, and how. Nephrology nursing journal : journal of the American Nephrology Nurses' Association Czajkowski, T., Pienkos, S., Schiller, B., Doss-McQuitty, S. 2013; 40 (1): 29-34; quiz 35

    Abstract

    Pre-dialysis education is known to impact modality choice among patients with end stage renal disease, but many of these patients report a lack of education in alternative dialysis therapies. Since 2004, Satellite Healthcare, a non-profit dialysis provider, has implemented chronic kidney disease education through Options classes at WellBound Centers, resulting in 23% of patients being treated with home therapies. The Satellite Healthcare-WellBound experience confirms that Options classes and a compelling infrastructure for home dialysis therapies are vital elements to bring alternative dialysis therapies to more patients.

    View details for PubMedID 23539802