Phillip I. Tarr, M.D.

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Division Chief, Gastroenterology, Hepatology and Nutrition
Co-Leader, Pathobiology Research Unit, Department of Pediatrics
Melvin E. Carnahan Professor of Pediatrics
Professor of Molecular Microbiology
Gastroenterology, Hepatology and Nutrition

phone: (314) 454-6173


  • BA, Brown University1975
  • MD, 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

  • 1984 - PresPediatrics - ABP
  • 1992 - PresPediatric Gastroenterology - ABP
  • 2002 - PresMO
  • 2012 - 2012BCS
  • 2013The American Board of Pediatrics (ABP) Maintenance of Certification (MOC)
  • 2016 - PresAR

Honors and Awards

  • 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

Recent Publications view all (211)

  1. Maternal activation of the EGFR prevents translocation of gut-residing pathogenic Escherichia coli in a model of late-onset neonatal sepsis. Proceedings of the National Academy of Sciences of the United States of America. 2020. doi:10.1073/pnas.1912022117  PMID:32179676  
  2. The Probiotic Conundrum: Regulatory Confusion, Conflicting Studies, and Safety Concerns. Journal of the American Medical Association. 2020;323(9):823-824. doi:10.1001/jama.2019.22268  PMID:32125410 
  3. The effect of legume supplementation on the gut microbiota in rural Malawian infants aged 6 to 12 months. American Journal of Clinical Nutrition (E-pub ahead of print). 2020. doi:10.1093/ajcn/nqaa011  PMID:32047925 
  4. Diagnostic Test Accuracy of Commercial Tests for Detection of Shiga Toxin-Producing Escherichia coli: A Systematic Review and Meta-Analysis Clinical Chemistry. 2020;1;66(2):302-315. doi:10.1093/clinchem/hvz006  PMID:32040589 
  5. A novel histological index for evaluation of environmental enteric dysfunction identifies geographic-specific features of enteropathy among children with suboptimal growth. PLOS Neglected Tropical Diseases. 2020. doi:10.1371/journal.pntd.0007975  PMID:31929525 
  6. Lactotrehalose, an Analog of Trehalose, Increases Energy Metabolism Without Promoting Clostridioides difficile Infection in Mice. Gastroenterology. 2019. doi:10.1053/j.gastro.2019.11.295  PMID:31838076 
  7. Discordant transmission of bacteria and viruses from mothers to babies at birth. Microbiome. 2019. doi:10.1186/s40168-019-0766-7  PMID:31823811 
  8. Contribution and Interaction of Shiga Toxin Genes to Escherichia coli O157:H7 Virulence. Toxins. 2019. doi:10.3390/toxins11100607  PMID:31635282 
  9. Transdermal fluorescence detection of a dual fluorophore system for noninvasive point-of-care gastrointestinal permeability measurement. Biomed Opt Express. 2019. doi:10.1364/BOE.10.005103  PMID:31646033 
  10. Persistent metagenomic signatures of early-life hospitalization and antibiotic treatment in the infant gut microbiota and resistome. Nat Microbiol. 2019. doi:10.1038/s41564-019-0550-2   PMID:31501537 
  11. Letter: Lactobacillus rhamnosus GG offers no benefit over placebo in children with acute gastroenteritis. Aliment Pharmacol Ther. 2019. doi:10.1111/apt.15418  PMID:31414542 
  12. Global Review of the Age Distribution of Rotavirus Disease in Children Aged <5 Years Before the Introduction of Rotavirus Vaccination. Clinical Infectious Diseases. 2019. doi:10.1093/cid/ciz060  PMID:30689799 
  13. Clinical interpretation of enteric molecular diagnostic tests. Clinical Microbiology and Infection. 2019. doi:10.1016/j.cmi.2019.08.018  PMID:31491461 
  14. Lactobacillus for Gastroenteritis in Children. Reply. N Engl J Med. 2019;380(19):e36. PMID:31067399 
  15. Impaired Chylomicron Assembly Modifies Hepatic Metabolism Through Bile Acid-Dependent and Transmissible Microbial Adaptations. Hepatology. 2019;70(4):1168-1184. doi:10.1002/hep.30669  PMCID:PMC6783349  PMID:31004524 
  16. Comparative Evaluation of Enteric Bacterial Culture and a Molecular Multiplex Syndromic Panel in Children with Acute Gastroenteritis. J Clin Microbiol. 2019. PMID:30971465 
  17. Pigment Visibility on Rectal Swabs Used to Detect Enteropathogens: A Prospective Cohort Study. J Clin Microbiol. 2019. PMID:30944189 
  18. Respiratory Medications in Infants <29 Weeks during the First Year Postdischarge: The Prematurity and Respiratory Outcomes Program (PROP) Consortium. J Pediatr. 2019. PMID:30857774 
  19. Performance of commercial tests for molecular detection of Shiga toxin-producing Escherichia coli (STEC): a systematic review and meta-analysis protocol. BMJ Open. 2019;9(3):e025950. PMID:30850413 
  20. Black Race Is Associated with a Lower Risk of Bronchopulmonary Dysplasia J Pediatr. 2019. PMID:30612812 
  21. Performance of Stool Testing Recommendations for Acute Gastroenteritis when Used to Identify Children with Nine Potential Bacterial Enteropathogens. Clin Infect Dis. 2018. PMID:30517612 
  22. Case definitions of hemolytic uremic syndrome following Escherichia coli O157:H7 infection vary in validity. Int J Med Microbiol. 2018;308(8):1121-1127. PMID:30466555 
  23. Lactobacillus rhamnosus GG versus Placebo for Acute Gastroenteritis in Children. N Engl J Med. 2018;379(21):2002-2014. PMID:30462938 
  24. Infant diet and maternal gestational weight gain predict early metabolic maturation of gut microbiomes. Nat Med. 2018. PMID:30374198 
  25. Strength of the association between antibiotic use and hemolytic uremic syndrome following Escherichia coli O157:H7 infection varies with case definition. Int J Med Microbiol. 2018;308(7):921-926. PMID:30257808 
  26. Diagnostic Interpretation Guidance for Pediatric Enteric Pathogens: A Modified Delphi Consensus Process. Can J Infect Dis Med Microbiol. 2018;2018:2589826. PMCID:PMC6180965  PMID:30363711 
  27. Gut Sphingolipid Composition as a Prelude to Necrotizing Enterocolitis. Sci Rep. 2018;8(1):10984. PMID:30030452 
  28. Relationship between Enteric Pathogen and Acute Gastroenteritis Disease Severity - A Prospective Cohort Study. Clin Microbiol Infect. 2018. PMID:29964235 
  29. Importance of case age in the purported association between phylogenetics and hemolytic uremic syndrome in Escherichia coli O157:H7 infections. Epidemiol Infect. 2018;1-6. PMID:29914582 
  30. Clinical and Laboratory Predictors of Shiga Toxin-Producing Escherichia coli Infection in Children With Bloody Diarrhea. J Pediatric Infect Dis Soc. 2018. PMID:29617871 
  31. Acute Responses to Diuretic Therapy in Extremely Low Gestational Age Newborns: Results from the Prematurity and Respiratory Outcomes Program Cohort Study. J Pediatr. 2018. PMID:29599068 
  32. Carriage of Cronobacter sakazakii in the very preterm infant gut. Clin Infect Dis. 2018. PMID:29394356 
  33. Geogenomic Segregation and Temporal Trends of Human Pathogenic Escherichia coli O157:H7, Washington, USA, 2005-20141. Emerg Infect Dis. 2018;24(1):32-39. PMCID:PMC5749469  PMID:29260688 
  34. Microbial antigen encounter during a preweaning interval is critical for tolerance to gut bacteria. Sci Immunol. 2017;2(18). PMCID:PMC5759965  PMID:29246946 
  35. Environmental Enteric Dysfunction: A Case Definition for Intervention Trials. Am J Trop Med Hyg. 2017;97(6):1643-1646. PMID:29016294 
  36. 2017 Infectious Diseases Society of America Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea. Clin Infect Dis. 2017;65(12):1963-1973. PMID:29194529 
  37. Serologic Evidence of Gut-driven Systemic Inflammation in Juvenile Idiopathic Arthritis. J Rheumatol. 2017;44(11):1624-1631. PMID:28916545 
  38. The Microbiome and Biomarkers for Necrotizing Enterocolitis: Are We Any Closer to Prediction? J Pediatr. 2017;189:40-47.e2. PMCID:PMC5614810  PMID:28669607 
  39. Randomised controlled trial of Lactobacillus rhamnosus (LGG) versus placebo in children presenting to the emergency department with acute gastroenteritis: the PECARN probiotic study protocol. BMJ Open. 2017;7(9):e018115. PMCID:PMC5623493  PMID:28947466 
  40. Measurement of gut permeability using fluorescent tracer agent technology. Sci Rep. 2017;7(1):10888. PMCID:PMC5589723  PMID:28883476 
  41. Case-Control Assessment of the Roles of Noroviruses, Human Bocaviruses 2, 3, and 4, and Novel Polyomaviruses and Astroviruses in Acute Childhood Diarrhea. J Pediatric Infect Dis Soc. 2017;6(3):e49-e54. PMID:28186546 
  42. Early pregnancy vaginal microbiome trends and preterm birth. Am J Obstet Gynecol. 2017;217(3):356.e1-356.e18. PMCID:PMC5581228  PMID:28549981 
  43. Enteropathogen detection in children with diarrhoea, or vomiting, or both, comparing rectal flocked swabs with stool specimens: an outpatient cohort study. Lancet Gastroenterol Hepatol. 2017;2(9):662-669. PMID:28712662 
  44. Impaired Barrier Function and Autoantibody Generation in Malnutrition Enteropathy in Zambia. EBioMedicine. 2017;22:191-199. PMCID:PMC5552244  PMID:28750860 
  45. Independence of gut bacterial content and neonatal necrotizing enterocolitis severity. J Pediatr Surg. 2017;52(6):993-998. PMCID:PMC5473614  PMID:28410788 
  46. Intestinal dysbiosis in preterm infants preceding necrotizing enterocolitis: a systematic review and meta-analysis. Microbiome. 2017;5(1):31. PMCID:PMC5343300  PMID:28274256 
  47. Environmental Enteric Dysfunction and the Fecal Microbiota in Malawian Children. Am J Trop Med Hyg. 2017;96(2):473-476. PMCID:PMC5303055  PMID:27956653 
  48. Associations Between Hydration Status, Intravenous Fluid Administration, and Outcomes of Patients Infected With Shiga Toxin-Producing Escherichia coli: A Systematic Review and Meta-analysis. JAMA Pediatr. 2017;171(1):68-76. PMID:27893870 
  49. Environmental Enteric Dysfunction Is Associated With Poor Linear Growth and Can Be Identified by Host Fecal mRNAs. J Pediatr Gastroenterol Nutr. 2016;63(5):453-459. PMCID:PMC5084633  PMID:27347722 
  50. Antibiotic perturbation of the preterm infant gut microbiome and resistome. Gut Microbes. 2016;7(5):443-9. PMCID:PMC5154371  PMID:27472377 
  51. Whole Genome Sequencing for Genomics-Guided Investigations of Escherichia coli O157:H7 Outbreaks. Front Microbiol. 2016;7:985. PMCID:PMC4928038  PMID:27446025 
  52. Development of the gut microbiota and mucosal IgA responses in twins and gnotobiotic mice. Nature. 2016;534(7606):263-6. PMCID:PMC4902178  PMID:27279225 
  53. Shiga Toxin-Producing Escherichia coli Infection, Antibiotics, and Risk of Developing Hemolytic Uremic Syndrome: A Meta-analysis. Clin Infect Dis. 2016;62(10):1251-1258. PMCID:PMC4845788  PMID:26917812 
  54. Gut bacteria dysbiosis and necrotising enterocolitis in very low birthweight infants: a prospective case-control study. Lancet. 2016;387(10031):1928-36. PMCID:PMC5553277  PMID:26969089 
  55. Droplet digital PCR quantifies host inflammatory transcripts in feces reliably and reproducibly. Cell Immunol. 2016;303:43-9. PMCID:PMC4863679  PMID:27063479 
  56. Developmental dynamics of the preterm infant gut microbiota and antibiotic resistome. Nat Microbiol. 2016;1:16024. PMCID:PMC5031140  PMID:27572443 
  57. Environmental Enteric Dysfunction Includes a Broad Spectrum of Inflammatory Responses and Epithelial Repair Processes. Cell Mol Gastroenterol Hepatol. 2016;2(2):158-174.e1. PMCID:PMC4769221  PMID:26973864 
  58. Gut Colonization of Healthy Children and Their Mothers With Pathogenic Ciprofloxacin-Resistant Escherichia coli. J Infect Dis. 2015;212(12):1862-8. PMCID:PMC4655851  PMID:25969564 
  59. 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. PMCID:PMC4722827  PMID:26397992 
  60. Impact of neonatal intensive care bed configuration on rates of late-onset bacterial sepsis and methicillin-resistant Staphylococcus aureus colonization. Infect Control Hosp Epidemiol. 2015;36(10):1173-82. PMCID:PMC5089903  PMID:26108888 
  61. Early life dynamics of the human gut virome and bacterial microbiome in infants. Nat Med. 2015;21(10):1228-34. PMCID:PMC4710368  PMID:26366711 
  62. The effect of dietary resistant starch type 2 on the microbiota and markers of gut inflammation in rural Malawi children. Microbiome. 2015;3:37. doi:10.1186/s40168-015-0102-9  PMCID:PMC4558878  PMID:26334878 
  63. Alberta Provincial Pediatric EnTeric Infection TEam (APPETITE): epidemiology, emerging organisms, and economics. BMC Pediatr. 2015;15:89. PMCID:PMC4521468  PMID:26226953 
  64. Real-Time PCR Assay for Detection and Differentiation of Shiga Toxin-Producing Escherichia coli from Clinical Samples. J Clin Microbiol. 2015;53(7):2148-53. PMCID:PMC4473226  PMID:25926491 
  65. Identification of Candidate Adherent-Invasive E. coli Signature Transcripts by Genomic/Transcriptomic Analysis. PLoS One. 2015;10(6):e0130902. PMCID:PMC4509574  PMID:26125937 
  66. Development of an enhanced human gastrointestinal epithelial culture system to facilitate patient-based assays. Gut. 2015;64(6):911-20. PMCID:PMC4305344  PMID:25007816 
  67. Respiratory consequences of prematurity: evolution of a diagnosis and development of a comprehensive approach. J Perinatol. 2015;35(5):313-21. doi:10.1038/jp.2015.19  PMCID:PMC4414744  PMID:25811285 
  68. Prematurity and respiratory outcomes program (PROP): study protocol of a prospective multicenter study of respiratory outcomes of preterm infants in the United States. BMC Pediatr. 2015;15:37. PMCID:PMC4407843  PMID:25886363 
  69. Agitation down-regulates immunoglobulin binding protein EibG expression in Shiga toxin-producing Escherichia coli (STEC). PLoS One. 2015;10(3):e0119583. PMCID:PMC4352079  PMID:25746924 
  70. Gut resistome development in healthy twin pairs in the first year of life. Microbiome. 2015;3:27. doi:10.1186/s40168-015-0090-9  PMCID:PMC4480905  PMID:26113976 
  71. Small bowel resection induces long-term changes in the enteric microbiota of mice. J Gastrointest Surg. 2015;19(1):56-64; discussion 64. PMCID:PMC4576885  PMID:25183407 
  72. Phenotypic and genotypic analysis of Clostridium difficile isolates: a single-center study. J Clin Microbiol. 2014;52(12):4260-6. PMCID:PMC4313296  PMID:25275005 
  73. Shiga toxin-producing Escherichia coli: a single-center, 11-year pediatric experience. J Clin Microbiol. 2014;52(10):3647-53. PMCID:PMC4187762  PMID:25078916 
  74. Patterned progression of bacterial populations in the premature infant gut. Proc Natl Acad Sci U S A. 2014;111(34):12522-7. PMCID:PMC4151715  PMID:25114261 
  75. Sepsis from the gut: the enteric habitat of bacteria that cause late-onset neonatal bloodstream infections. Clin Infect Dis. 2014;58(9):1211-8. PMCID:PMC3982840  PMID:24647013 
  76. Heteropathogenic virulence and phylogeny reveal phased pathogenic metamorphosis in Escherichia coli O2:H6. EMBO Mol Med. 2014;6(3):347-57. PMCID:PMC3958309  PMID:24413188 
  77. Genome Sequence of Escherichia coli O157:H7 Strain 2886-75, Associated with the First Reported Case of Human Infection in the United States. Genome Announc. 2014;2(1). PMCID:PMC3886948  PMID:24407635 
  78. Fecal carriage of methicillin-resistant Staphylococcus aureus and vancomycin-resistant Enterococcus in healthy children. Antimicrob Agents Chemother. 2014;58(2):1261-2. PMCID:PMC3910844  PMID:24277049 
  79. Precise dissection of an Escherichia coli O157:H7 outbreak by single nucleotide polymorphism analysis. J Clin Microbiol. 2013;51(12):3950-4. PMCID:PMC3838074  PMID:24048526 
  80. Viral co-infections are common and are associated with higher bacterial burden in children with clostridium difficile infection. J Pediatr Gastroenterol Nutr. 2013;57(6):813-6. PMCID:PMC4098970  PMID:23838821 
  81. Intestinal inflammatory biomarkers and outcome in pediatric Clostridium difficile infections. J Pediatr. 2013;163(6):1697-1704.e2. PMCID:PMC4098967  PMID:24011765 
  82. Pediatric fecal microbiota harbor diverse and novel antibiotic resistance genes. PLoS One. 2013;8(11):e78822. PMCID:PMC3827270  PMID:24236055 
  83. Validation of the modified Vesikari score in children with gastroenteritis in 5 US emergency departments. J Pediatr Gastroenterol Nutr. 2013;57(4):514-9. PMCID:PMC3788842  PMID:23676445 
  84. Dysregulation of angiopoietin 1 and 2 in Escherichia coli O157:H7 infection and the hemolytic-uremic syndrome. J Infect Dis. 2013;208(6):929-33. PMCID:PMC3749007  PMID:23801605 
  85. Gastrointestinal viruses were not found as an aetiology of culture-negative illness in NICU patients. Arch Dis Child Fetal Neonatal Ed. 2013;98(4):F374-5. PMID:23563694 
  86. Markers of intestinal inflammation, not bacterial burden, correlate with clinical outcomes in Clostridium difficile infection. Clin Infect Dis. 2013;56(12):1713-21. PMCID:PMC3707425  PMID:23487367 
  87. Whole-Genome Draft Sequences of 26 Enterohemorrhagic Escherichia coli O157:H7 Strains. Genome Announc. 2013;1(2):e0013412. PMCID:PMC3593324  PMID:23516226 
  88. Biogeography of the ecosystems of the healthy human body. Genome Biol. 2013;14(1):R1. PMCID:PMC4054670  PMID:23316946 
  89. Use and accuracy of diagnostic imaging by hospital type in pediatric appendicitis. Pediatrics. 2013;131(1):e37-44. PMCID:PMC3529953  PMID:23266930 
  90. Detection of low-concentration host mRNA transcripts in Malawian children at risk for environmental enteropathy. J Pediatr Gastroenterol Nutr. 2013;56(1):66-71. PMID:22832511 
  91. Diarrhea etiology in a pediatric emergency department: a case control study. Clin Infect Dis. 2012;55(7):897-904. PMCID:PMC3657524  PMID:22700832 
  92. Editorial commentary: Escherichia coli O104:H4 and hemolytic uremic syndrome: the analysis begins. Clin Infect Dis. 2012;55(6):760-3. PMID:22670035 
  93. Risk factors for the hemolytic uremic syndrome in children infected with Escherichia coli O157:H7: a multivariable analysis. Clin Infect Dis. 2012;55(1):33-41. PMCID:PMC3493180  PMID:22431799 
  94. Azithromycin decolonization of STEC--a new risk emerges. Nat Rev Nephrol. 2012;8(7):429. PMID:22664737 
  95. The CXCR4/CXCR7/SDF-1 pathway contributes to the pathogenesis of Shiga toxin-associated hemolytic uremic syndrome in humans and mice. J Clin Invest. 2012;122(2):759-76. PMCID:PMC3266777  PMID:22232208 
  96. Early volume expansion during diarrhea and relative nephroprotection during subsequent hemolytic uremic syndrome. Arch Pediatr Adolesc Med. 2011;165(10):884-9. PMCID:PMC4064458  PMID:21784993 
  97. The age of necrotizing enterocolitis onset: an application of Sartwell's incubation period model. J Perinatol. 2011;31(8):519-23. PMCID:PMC3145821  PMID:21273988 
  98. Obscured phylogeny and possible recombinational dormancy in Escherichia coli. BMC Evol Biol. 2011;11:183. PMCID:PMC3152902  PMID:21708031 
  99. Bacterial DNA content in the intestinal wall from infants with necrotizing enterocolitis. J Pediatr Surg. 2011;46(6):1029-33. PMCID:PMC3118995  PMID:21683193 
  100. Enterohaemorrhagic Escherichia coli haemolysin is cleaved and inactivated by serine protease EspPα. Environ Microbiol. 2011;13(5):1327-41. PMCID:PMC3472028  PMID:21352460 
  101. Chromosomal instability in enterohaemorrhagic Escherichia coli O157:H7: impact on adherence, tellurite resistance and colony phenotype. Mol Microbiol. 2011;79(4):1024-44. PMCID:PMC3064760  PMID:21299654 
  102. Further evidence of constrained radiation in the evolution of pathogenic Escherichia coli O157:H7. Infect Genet Evol. 2010;10(8):1282-5. PMCID:PMC3742067  PMID:20691811 
  103. Bacterial macroscopic rope-like fibers with cytopathic and adhesive properties. J Biol Chem. 2010;285(42):32336-42. PMCID:PMC2952234  PMID:20688909 
  104. Proinflammatory fecal mRNA and childhood bacterial enteric infections. Gut Microbes. 2010;1(4):209-212. PMCID:PMC3023602  PMID:21327027 
  105. Shiga toxin 1 interaction with enterocytes causes apical protein mistargeting through the depletion of intracellular galectin-3. Exp Cell Res. 2010;316(4):657-66. PMCID:PMC2815162  PMID:19744479 
  106. Deer sausage: a newly identified vehicle of transmission of Escherichia coli O157:H7. J Pediatr. 2009;155(4):587-9. PMID:19773004 
  107. A method for isolating and analyzing human mRNA from newborn stool. J Immunol Methods. 2009;349(1-2):56-60. PMCID:PMC2850193  PMID:19660464 
  108. The Escherichia coli ycbQRST operon encodes fimbriae with laminin-binding and epithelial cell adherence properties in Shiga-toxigenic E. coli O157:H7. Environ Microbiol. 2009;11(7):1815-26. PMCID:PMC2888687  PMID:19508558 
  109. A precise reconstruction of the emergence and constrained radiations of Escherichia coli O157 portrayed by backbone concatenomic analysis. Proc Natl Acad Sci U S A. 2009;106(21):8713-8. PMCID:PMC2689004  PMID:19439656 
  110. Parental management of childhood diarrhea. Clin Pediatr (Phila). 2009;48(3):295-303. PMID:19023110 
  111. Tri-county comprehensive assessment of risk factors for sporadic reportable bacterial enteric infection in children. J Infect Dis. 2009;199(4):467-76. PMCID:PMC3693595  PMID: