Short-term azithromycin may reduce ureaplasma infection-related morbidity in preterm infants
Preterm infants who tested positive for ureaplasma respiratory tract infection had poorer survival over the first year of life, according to a study presented at ERS 2018. However, a 3-day course of prophylactic azithromycin could potentially reduce this morbidity and mortality burden.
Participants in this prospective, multicentre, double-blind trial were 121 infants born at a gestational age of 24–28 weeks who were randomized to receive intravenous azithromycin (20 mg/kg; n=60) or placebo (n=61) once a day for 3 days.
Tracheal or nasopharyngeal samples were taken both before and after drug or placebo administration and parents of the infants completed respiratory health-related questionnaires at 6 and 12 months. Forty-four infants (36.3 percent) tested positive for ureaplasma infection, with a higher rate (45 percent) observed among more premature infants (born at 24–26 weeks gestation).
At 12 months, infants who tested positive for ureaplasma infection on tracheal samples had poorer survival compared with those who tested negative (71 percent vs 90 percent) or those who only tested positive on nasopharyngeal specimens (100 percent). [ERS 2018, abstract OA301]
Infants who tested positive for ureaplasma infection on tracheal samples were also more at risk of developing bronchopulmonary dysplasia and other respiratory issues over the first 12 months of life compared with those who tested negative (67 percent vs 50 percent) or those with positive nasopharyngeal samples only (21 percent), and also had poorer bronchopulmonary dysplasia-free survival (33, 50, and 79 percent, respectively).
Infants with a ureaplasma infection-positive tracheal sample who received azithromycin had a significantly reduced risk of death or severe respiratory morbidity at 12 months compared with those who received placebo (33 percent vs 86 percent; p=0.036).
“We believe that ureaplasma bacteria can interact with a mother’s and baby’s immune defences leading to a chronic infection with persistent inflammation. This can then lead to premature labour or early rupture of the membranes. In a premature baby, inflammation alters the development of the immature lung, contributing to the development of bronchopulmonary dysplasia,” said study author Professor Rose Marie Viscardi from the University of Maryland, Baltimore, Maryland, US, who presented the findings.
“This study shows that ureaplasma respiratory infection is very common in extremely premature infants and clinicians should consider testing for this infection in those newborns who are at risk. It also suggests that the 3-day course of azithromycin is safe and effective,” she said, cautioning that present evidence does not support routine treatment of ureaplasma respiratory infection.
“There is currently no consensus among neonatal specialists on whether to test for ureaplasma, or whether to give treatment if the bacteria are detected. Ureaplasma are not picked up by routine tests for infections and require specialized lab tests. These bacteria are not considered dangerous in healthy people so many clinicians do not think treatment is necessary,” said ERS President-Elect Professor Tobias Welte who was not involved in the study.
“However, this study suggests that in very premature babies this infection is linked with bronchopulmonary dysplasia and a higher risk of death. Larger clinical trials are needed to clarify the importance of detecting ureaplasma in premature babies and to show whether treatment with antibiotics is beneficial. Until then, antibiotic treatment should not be used routinely,” he said.