Antibiotic Linked To Newborns' Intestinal Disorder

Pyloric stenosis, which usually occurs in the first or second month of life, is a blockage of the outlet of the stomach that causes projectile vomiting, leading to weight loss and dehydration. It is the most common indication for abdominal surgery in infancy.

"The link between erythromycin and pyloric stenosis is an important finding which will make a difference to the health of babies," said the study's principal investigator, Barbara E. Mahon, M.D., M.P.H., a clinical assistant professor of pediatrics at the IU School of Medicine.

Using clinical data extracted from the Regenstrief Medical Record System -- a comprehensive electronic medical records system that gathers and stores data including diagnoses, radiology and operative reports, pharmacy records, and physician observations -- the researchers studied 14, 876 babies born between June 1993 and December 1999. They found that if given erthromycin during the first two weeks of life, babies were 10.5 times more likely to develop pyloric stenosis than babies who were not given the antibiotic.

"This large scale study could only have been undertaken with the vast amount of data available in the Regenstrief system," said Dr. Mahon. Co-authors of the study are Marc Rosenman, M.D. a health services research fellow at the Regenstrief Institute for Healthcare ,and Martin Kleiman, M.D., Ryan White Professor of Pediatrics at the IU School of Medicine.

The newborns were given erthromycin by mouth in a 10-to-14 day course, usually because of maternal chlamydia at the time of delivery. Erythromycin has had a long history as a useful, safe, and generally well-tolerated drug, the researchers reported. However, as a result of their study they say that the antibiotic should be used only with prudence in the first two weeks of life.

The IU School of Medicine study also showed that babies who received an erythromycin eye ointment, a common treatment for conjunctivitis, did not have a higher risk of pyloric stenosis.