The Development of Intestinal Dysbiosis in Anemic Preterm Infants

OBJECTIVE: Anemia and Proteobacteria-dominant intestinal dysbiosis in very low birth weight (VLBW) infants have been linked to necrotizing enterocolitis, a severe gut inflammatory disease. We hypothesize that anemia of prematurity is related to the development of intestinal dysbiosis. STUDY DESIGN: 342 weekly stool samples collected prospectively from 80 VLBW infants were analyzed for bacterial microbiomes (with 16S rRNA). Linear mixed effects model was used to determine the relationships between the onsets of anemia and intestinal dysbiosis. RESULTS: Hematocrit was associated with intestinal microbiomes, with lower Hct occurring with increased Proteobacteria and decreased Firmicutes. Infants with a hematocrit <30% had intestinal microbiomes that diverged toward Proteobacteria dominance and low diversity after the first postnatal month. The microbiome changes were also related to the severity of anemia. CONCLUSIONS: This finding supports a potential microbiological explanation for anemia as a risk factor for intestinal dysbiosis in preterm infants.