This article is more than 5 years old. Information may no longer be current.

Antibiotic use in preterm infants harms gut microbiome, contributes to resistance

Gautam Dantas

Approximately 99% of infants who are born with very low birth weight receive antibiotics within the first 2 days of life, contributing to antibiotic resistance and the destruction of helpful bacteria in the gut microbiome, according to a presentation at the NIH’s workshop, “The Human Microbiome: Emerging Themes at the Horizon of the 21st Century.”

This antibiotic use leaves preterm and low birth weight infants susceptible to infection from bacteria such as Escherichia coli, Klebsiella pneumoniae and other urgent threat pathogens.

“We are interested in the natures of specific antibiotics that create responses from microbiomes and understanding the collateral damage that these antibiotics might engender,” Gautam Dantas, PhD, associate professor in the departments of pathology and immunology, biomedical engineering and molecular microbiology at Washington University School of Medicine in St. Louis, said in the presentation. “This might influence choices made from a first-line medicine perspective.”

Dantas mentioned that the top two medications that an infant receives in the NICU are antibiotics, and that four of the top eight most commonly used medications include antimicrobials. These drugs include ampicillin, gentamicin, cefotaxime and vancomycin.

Predictors of antibiotic use and a lower richness of gut microbiomes include the use of a NICU hospital room, 10 total days of antibiotics, the method of delivery, feeding choices (breast milk vs. formula), other medications, maternal health and infant infection.

Dantas notes that this information is of particular importance because antibiotic-resistant infections are predicted to cause 10 million estimated deaths and cost $100 trillion to the global economy in 2050.

“The reason we care about the microbiome in preterm infants is because of the high risk of infections,” Dantas said. “They receive an insane assortment of antibiotics. We have this cohort of kids born about 10 weeks too early, and almost every one of them receives antibiotics for the first few days of life. If you think about it, there is a developing ecosystem that we are carpet-bombing with things that are going to disrupt it.” – by Katherine Bortz