We have all, I hope, come to understand that prescribing an antibiotic requires judicious consideration of the drug’s risks and benefits. There should be a clear indication for use, usually an active infection. There are exceptions.
Preterm and low birth weight babies are prone to particular infections with a high mortality rate. One of these is necrotizing enterocolitis, with a mortality rate of 50 percent. It is standard to give these delicate infants antibiotics to prevent, not treat, these deadly infections. The risks associated with preventive antibiotics are fewer than the high risks of infection. A new study, finds that early life exposure to antibiotics in neonatal mice has adverse effects on the gut into adulthood. The antibiotics interfere with the development of a normal, healthy, gut microbiome, enteric nervous system, and gut function.
The research, led by Dr. Jaime Foong from the Department of Anatomy and Physiology at the University of Melbourne, is the first to show that antibiotics given to neonatal mice have these long-lasting effects which result in disturbed gastrointestinal function. This includes the speed of motility through the gut and diarrhea-like symptoms in adulthood.
Researchers gave mice an oral dose of vancomycin every day for the first ten days of their lives. Their care was otherwise routine until they were young adults. Then, their gut tissue was examined to measure structure, function, microbiota, and nervous system.
Changes were also dependent on the sex of the mice. The females had long whole gut transit, and males had lower fecal weight than the control group. Both males and females had greater fecal water content than controls, with diarrhea.
Mice have many similarities to humans, but they are born with more immature guts than humans, with accelerated growth due to their shorter lifespans. Their gut microbiota and nervous systems are simpler than humans, so it cannot be assumed that human infants and children will have identical effects with interventions identical to those performed on mice.
The researchers will be doing further studies on the mechanisms of antibiotics on the gut and the causes of the sex-specific actions, as well as antibiotic effects on metabolism and brain function.
“We are very excited about the findings of our study which show that antibiotics given after birth could have prolonged effects on the enteric nervous system,” Dr. Foong says in a statement. “This provides further evidence of the importance of microbiota on gut health and could introduce new targets to advance antibiotic treatment to very young children.”
The research paper is published in The Journal of Physiology.