Phillip I. Tarr, M.D.

Director, Division of Pediatric Gastroenterology and Nutrition
Professor of Molecular Microbiology
Co-Leader, Pathobiology Research Unit, Department of Pediatrics
Gastroenterology, Hepatology and NutritionPathobiologyMolecular Microbiology

phone: 314-286-2848

Research Interests

Dr. Phillip Tarr is the Melvin E. Carnahan Professor of Pediatrics, and Director of the Division of Pediatric Gastroenterology, Hepatology, and Nutrition at Washington University School of Medicine. He co-directs the Pediatrics Pathobiology Research Unit, and is a Professor of Molecular Microbiology. He obtained his MD degree from Yale University School of Medicine in 1980, and completed clinical training in pediatrics, pediatric gastroenterology and pediatric infectious diseases at the University of Washington/Seattle Children’s Hospital, where he remained on the faculty until 2003 when he assumed his present position. Dr. Tarr has had an abiding interest in many different aspects of enteric infections and gut microbiology, with a focus on pediatrics. His chief contributions have been in the field of diarrheagenic Escherichia coli, especially E. coli O157:H7. His work has helped delineate the epidemiology, pathophysiology, and medical management of illnesses caused by this pathogen. He has long advocated the role of accurate and thorough enteric diagnostics as a mainstay of clinical care. His current research is centered on the role of the gut microbiome in childhood development and growth. The diseases he studies include necrotizing enterocolitis, tropical enteropathy, and inflammatory bowel diseases.


  • B.A., Brown University1975
  • M.D., Yale University School of Medicine1980


  • Intern/Resident, University of Washington School of Medicine/Children's Orthopedic Hospital and Medical Center1980 - 1983
  • Senior Fellow, University of Washington School of Medicine1983 - 1987
  • Fellow, University of Washington School of Medicine and Children's Hospital and Medical Center 1988 - 1989

Licensure and Board Certification

  • Pediatrics - ABP1984
  • Pediatric Gastroenterology - ABP1992
  • MO, 2002
  • BCS2012
  • The American Board of Pediatrics (ABP) Maintenance of Certification (MOC)2013


  • American Gastroenterological Association/Blackwell Scientific Research Scholar Award1992 - 1995
  • Food and Drug Administration Commissioner's Special Citation1997 - 1997
  • Melvin E. Carnahan Professor of Pediatrics, Endowed Chair2004 - Pres

Selected Publications view all (10)

  1. Gasparrini AJ, Crofts TS, Gibson MK, Tarr PI, Warner BB, Dantas G. Antibiotic perturbation of the preterm infant gut microbiome and resistome. Gut Microbes. 2016;0. PMID:27472377  
  2. Ordiz MI, Shaikh N, Trehan I, Maleta K, Stauber J, Shulman R, Devaraj S, Tarr PI, Manary MJ. Environmental Enteric Dysfunction is Associated with Poor Linear Growth and Can be Identified by Host Fecal mRNAs. J Pediatr Gastroenterol Nutr. 2016. doi:10.1097/MPG.0000000000001315  PMID:27347722  
  3. Planer JD, Peng Y, Kau AL, Blanton LV, Ndao IM, Tarr PI, Warner BB, Gordon JI. Development of the gut microbiota and mucosal IgA responses in twins and gnotobiotic mice. Nature. 2016;534(7606):263-6. doi:10.1038/nature17940  PMCID:PMC4902178  PMID:27279225  
  4. Freedman SB, Xie J, Neufeld MS, Hamilton WL, Hartling L, Tarr PI, Alberta Provincial Pediatric Enteric Infection Team (APPETITE). Shiga Toxin-Producing Escherichia coli Infection, Antibiotics, and Risk of Developing Hemolytic Uremic Syndrome: A Meta-analysis. Clin Infect Dis. 2016;62(10):1251-8. doi:10.1093/cid/ciw099  PMCID:PMC4845788  PMID:26917812  
  5. Stauber J, Shaikh N, Ordiz MI, Tarr PI, Manary MJ. Droplet digital PCR quantifies host inflammatory transcripts in feces reliably and reproducibly. Cell Immunol. 2016;S0008-8749(16):30016-8. doi:10.1016/j.cellimm.2016.03.007  PMID:27063479  
  6. Warner BB, Deych E, Zhou Y, Hall-Moore C, Weinstock GM, Sodergren E, Shaikh N, Hoffmann JA, Linneman LA, Hamvas A, Khanna G, Rouggly-Nickless LC, Ndao IM, Shands BA, Escobedo M, Sullivan JE, Radmacher PG, Shannon WD, Tarr PI. Gut bacteria dysbiosis and necrotising enterocolitis in very low birthweight infants: a prospective case-control study. Lancet. 2016;S0140-6736(16):00081-7. doi:10.1016/S0140-6736(16)00081-7  PMID:26969089  
  7. Gibson M.K., Wang B., Ahmadi S., Burnham C.A., Tarr P.I., Warner B.B., Dantas G. Developmental dynamics of the preterm infant gut microbiota and antibiotic resistome Nature Microbiology. 2016;1:16024. 
  8. Yu J, Ordiz MI, Stauber J, Shaikh N, Trehan I, Barnell E, Head RD, Maleta K, Tarr PI, Manary MJ. Environmental Enteric Dysfunction Includes a Broad Spectrum of Inflammatory Responses and Epithelial Repair Processes. Cell Mol Gastroenterol Hepatol. 2016;2(2):158-174.e1. doi:10.1016/j.jcmgh.2015.12.002  PMCID:PMC4769221  PMID:26973864  
  9. Rusconi B, Sanjar F, Koenig SS, Mammel MK, Tarr PI, Eppinger M. Whole Genome Sequencing for Genomics-Guided Investigations of Escherichia coli O157:H7 Outbreaks. Front Microbiol. 2016;7:985. PMID:27446025  
  10. Poindexter BB, Feng R, Schmidt B, Aschner JL, Ballard RA, Hamvas A, Reynolds AM, Shaw PA, Jobe AH, Prematurity and Respiratory Outcomes Program. Comparisons and Limitations of Current Definitions of Bronchopulmonary Dysplasia for the Prematurity and Respiratory Outcomes Program. Ann Am Thorac Soc. 2015;12(12):1822-30. doi:10.1513/AnnalsATS.201504-218OC  PMCID:PMC4722827  PMID:26397992