LAUSR

BACKGROUND There is little data on gut microbiome and various factors that lead to dysbiosis in pediatric intestinal failure (PIF). This study aimed to characterize gut microbiome in PIF and determine factors that may affect microbial composition in these patients. METHODS This is a single-center, prospective cohort study of children with PIF followed at our intestinal rehabilitation program. Stool samples were collected longitudinally at regular intervals over a one-year period. Medical records were reviewed, and demographic and clinical data were collected. Medication history including the use of acid blockers, scheduled prophylactic antibiotics and bile acid sequestrants, was obtained. Gut microbial diversity among patients was assessed and compared according to various host characteristics of interest. RESULTS The final analysis included 74 specimens from 12 subjects. Scheduled prophylactic antibiotics, presence of central line associated bloodstream infection (CLABSI) at the time of specimen collection, use of acid blockers and ≥ 50% calories delivered via parenteral nutrition (PN) was associated with reduced alpha diversity, whereas increasing age was associated with improved alpha diversity at various microbial levels (p-value<0.05). Beta diversity differed with age, presence of CLABSI, use of scheduled antibiotics, acid blockers, percent calories via PN and presence of oral feeds at various microbial levels (p-value <0.05). Single taxon analysis identified several taxa at several microbial levels which were significantly associated with various host characteristics. CONCLUSION Gut microbial diversity in PIF subjects is influenced by various factors involved in the rehabilitation process including medications, percent calories received parenterally, CLABSI events, the degree of oral feeding and age. Additional investigation performed across multiple centers is needed to further understand the impact of these findings on important clinical outcomes in PIF.