Association between colonization of the respiratory tract with Ureaplasma species and bronchopulmonary dysplasia in newborns with extremely low gestational age: a retrospective study

AIM: To ascertain the incidence of respiratory tract colonization in extremely low gestational age newborns (ELGANs) with Ureaplasma parvum and Ureaplasma urealyticum and determine if there is a difference in the severity of bronchopulmonary dysplasia (BPD) between ELGANs with and without Ureaplasma species (spp) colonization. METHODS: We reviewed the medical records of ELGANs 23 0/7–27 6/7 weeks of gestation, tested for U. parvum and U. urealyticum in our Center from January 1, 2009 to December 31, 2019. Ureaplasma spp were identified with the Mycofast Screening Revolution assay based on liquid broth cultures or with polymerase chain reaction. RESULTS: This study enrolled 196 preterm newborns. Fifty (25.5%) newborns had Ureaplasma spp respiratory tract colonization, with U. parvum being the predominant species. The incidence rate of respiratory tract colonization with Ureaplasma spp slightly increased in the studied period. The incidence rate for 2019 was 16.2 per 100 infants. BPD severity significantly correlated with Ureaplasma spp colonization (P = 0.041). After controlling for other risk factors for BPD in a regression model, preterm infants colonized with Ureaplasma spp had 4.32 times (95% confidence interval, CI 1.20-15.49) higher odds for developing moderate-to-severe BPD. CONCLUSIONS: U. parvum and U. urealyticum could be associated with the development of BPD in ELGANs.