Early Acquisition of Pneumocystis jirovecii Colonization and Potential Association With Respiratory Distress Syndrome in Preterm Newborn Infants.

Background: Pneumocystis pneumonia is a well-recognized lung disease of premature and malnourished babies. Even though serologic studies have shown that children are exposed to Pneumocystis jirovecii early in life, the epidemiology of human P. jirovecii infection and the host-microorganism relationship in infancy remain poorly understood. The aim of the present study was to investigate the prevalence of P. jirovecii colonization in preterm infants and its possible association with medical complications.

Methods: A prospective observational study of preterm infants (birth weight <1500 g and/or gestational age <32 weeks) was carried out. Identification of P. jirovecii colonization was performed by means of molecular techniques in nasal aspirated samples at birth.

Results: A total of 128 preterm infants were included during the study period. Pneumocystis DNA was identified in 25.7% (95% confidence interval [CI], 17.8%-33.7%) of newborns studied. A significant increase of respiratory distress syndrome in colonized group, even after adjusting for confounding factors (odds ratio, 2.7 [95% CI, 1.0-7.5]; P = .04), was observed. No differences were observed in other medical conditions between the 2 groups.

Conclusions: Pneumocystis jirovecii colonization is frequent in preterm births and could be a risk factor to develop respiratory distress syndrome among preterm infants.