The Association Between Respiratory Tract Colonisation with Ureaplasma parvum and Ureaplasma urealyticum and Bronchopulmonary Dysplasia in Extremely Low Gestational Age Newborns: 11-years retrospective study in a single tertiary centre

Abstract Purpose. With this 11-year long retrospective study (2009–2019) we wanted to ascertain the incidence of respiratory tract colonisation of extremely low gestational age newborns (ELGANs) with Ureaplasma parvum and Ureaplasma urealyticum and if there is a difference in the severity of bronchopulmonary dysplasia (BPD) between preterm infants with proven respiratory tract colonisation with U. parvum and U. urealyticum and without colonisation, controlled for other risk factors for BPD. Methods. We reviewed the medical records of ELGANs 23 0/7–27 6/7 weeks of gestation, tested for U. parvum and U. urealyticum. The causative Ureaplasma species (spp.) were identified using Mycofast Screening Revolution assay based on liquid broth cultures or with the PCR method. Results. This study included 196 preterm newborns. Fifty (25.5%) newborns had Ureaplasma spp. respiratory tract colonisation, with U. parvum being the predominant species. The results showed a slightly growing incidence rate of respiratory tract colonisation with Ureaplasma spp. in the observed period. The incidence rate for 2019 was 16.2 per 100 infants. We also discovered a statistically significant correlation between the severity of BPD and the colonisation with Ureaplasma spp. (p=0.041). Controlling for other risk factors for BPD in the regression model, the preterm infants colonised with Ureaplasma spp. had 4.32-times (95% confidence interval, CI 1.20–15.49) higher odds for developing moderate to severe BPD. Conclusions. Our results suggest that U. parvum and U. urealyticum could be associated with the development of BPD in ELGANs.