Clinical significance of Ureaplasma species in bronchopulmonary dysplasia development in preterm infants

This prospective study aimed to investigate colonization of Ureaplasma spp. in preterm infants to evaluate the relationship between Ureaplasma spp. colonization and BPD including other neonatal morbidities. A cohort of 357 preterm infants was examined for Ureaplasma spp. detection. Samples as nasopharyngeal swabs and gastric aspirates (non-intubated infants) whereas tracheal aspirates (intubated infants), were collected within 24 h of birth from infants with < 37 weeks gestational age (GA). Each sample was tested with culture and real-time polymerase chain reaction (RT-PCR) to confirm Ureaplasma spp. colonization. A total of 12 (3.3%) preterm infants (GA, 30.5 ± 2.2 weeks, P = 0.001; BW, 1,529 ± 501 g, P = 0.005) were positive for Ureaplasma spp. colonization. 23 (6.8%) preterm infants (GA, 28.7 ± 1.1 weeks, P = 0.001; BW, 1,234 ± 441 g, P = 0.005) developed BPD. Ureaplasma spp. colonization and BPD development showed an inverse relation with GA and birth weight (BW), and were associated with one antenatal factor (premature rupture of membranes; PROM), two natal factors (smaller GA, lower BW), one postnatal factor (longer use of supplemental oxygen), and p-value was significant for all factors (P < 0.05). Incidence of BPD in Ureaplasma spp. positive group was higher than in Ureaplasma spp. negative group (n = 3, 25% vs. n = 20, 6%, P = 0.001). Multivariate logistic regression analysis revealed a common correlation of Ureaplasma spp. colonization and BPD development with smaller GA (P = 0.012 & 0.001; 95%CI: 0.590-0.937 & 0.181-0.627), independent correlation of Ureaplasma spp. colonization with PROM (P = 0.002; 95%CI: 2.226-35.547) whereas independent correlation of BPD development with Ureaplasma spp. colonization (P = 0.037; 95%CI: 1.167-123.809) and more ventilator days (P = 0.003; 95%CI: 1.197-2.486). Ureaplasma spp. colonization is associated with PROM, smaller GA, and higher incidence of BPD. All preterm infants delivered by mothers with PROM and/or with smaller GAs should be investigated for Ureaplasma spp. colonization to anticipate BPD incidence.