Study shows possible benefit of azithromycin in pregnancy
Giving pregnant women a dose of azithromycin during labor reduces infections in both mothers and newborns, according to a new study in Pediatrics. But an accompanying commentary suggests the harms of azithromycin exposure could outweigh the benefits.
In a post-hoc analysis of a double-blind, placebo-controlled randomized trial, 829 Gambian women were given either an oral dose of azithromycin or a placebo. Investigators were looking to see whether the intervention had an effect on maternal and neonatal clinical infections such as sepsis, which is a high risk in sub-Saharan Africa because of poor nutrition and unhygienic delivery conditions. In Gambia, the authors note, neonatal deaths represent 40% of all deaths in children under the age of 5, and maternal mortality is among of the highest in the developing world.
Overall, the researchers found that maternal infections were lower in the azithromycin group than in the placebo group (3.6% vs. 9.2%), as was the prevalence of mastitis (1.4% vs. 5.1%) and fever (1.9% vs. 5.8%). The overall prevalence of infections was also lower among the newborns of the azithromycin group (18.1% vs. 23.8%), with a marked difference in skin infections (3.1% vs. 6.4%).
"Our results show that azithromycin administered to women in labor reduces maternal and neonatal infections and maternal episodes of fever," the authors write. "Larger trials designed to assess the effect of the intervention on severe morbidity and mortality are urgently needed."
But as noted in the accompanying commentary from two members of the American Academy of Pediatrics Committee on Infectious Diseases, the decrease in infections among the azithromycin group was driven primarily by mastitis in the mothers and skin infections in neonates, none of which were described as severe. In addition, no significant difference in rates of sepsis, malaria, hospitalizations, or deaths in mothers or infants were observed.
Furthermore, the commentary authors write, azithromycin exposure may facilitate the emergence of antimicrobial resistance, could alter the structure and function of the human microbiome, and has been associated with the development of hypertrophic pyloric stenosis in infants.
"In light of the small potential benefits observed in the Oluwalana study, the potential harms of azithromycin exposure likely outweigh the upside for this specific indication," the authors write. They suggest that future studies should assess azithromycin's effects on serious maternal and neonatal infections and evaluate potential harms.
Jan 27 Pediatrics study
Jan 27 Pediatrics commentary
Research highlights how antibiotics can stimulate bacterial reproduction
A study today in Ecology and Evolution shows that growth of bacteria can be boosted by antibiotics.
In the study, researchers from the University of Exeter in Great Britain were looking to determine the fitness costs associated with antibiotic resistance in Escherichia coli when exposed to the antibiotic doxycycline. Their working assumption was that the bacteria that acquired resistance mutations might proliferate more slowly.
To investigate, the researchers exposed E coli bacteria to eight rounds of antibiotic therapy over 4 days. As expected, the bacteria grew more resistant with each round of treatment. But what was unexpected was that the mutated E. coli reproduced faster after antibiotic exposure and formed much larger populations than bacteria exposed to no antibiotics. Furthermore, the ability to reproduce faster remained after antibiotic exposure ended.
"Our research suggests there could be added benefits for E.coli bacteria when they evolve resistance to clinical levels of antibiotics," lead author Robert Beardmore, BSc, said in a University of Exeter press release. "Bacteria have a remarkable ability to rearrange their DNA and this can stop drugs working, sometimes in a matter of days."
Jan 30 Ecol Evol study
Jan 30 University of Exeter press release
