[Clinical significance of Ureaplasma urealyticum in bronchopulmonary dysplasia of prematurity]

Abstract

Objective: To investigate the association of Ureaplasma urealyticum (UU) infection with the incidence of bronchopulmonary dysplasia (BPD), to compare the clinical manifestations and prognosis of BPD infants with or without Ureaplasma urealyticum infection.

Method: Data were retrospectively collected between January 2004 and June 2011. All infants whose gestational age was ≤ 32 w and survived at 36 w were included in this study. Endotracheal aspirates were collected for UU polymerase chain reaction (PCR) within the first 48 hr of life. Statistical analyses were performed by using SPSS 11.5 software. The clinical characteristics of infants in the two groups were compared. The association of UU infection and BPD was analyzed and the clinical manifestations and prognosis of BPD in the two groups were compared.

Result: The results of PCR for UU were positive while that for other pathogens were negative in 168 infants whose chest X rays confirmed pulmonary inflammatory changes (UU group). The results of PCR for UU were negative in 393 infants (non-UU group). Except for premature rupture of membranes >24 hr, the rates of vaginal delivery, neonatal respiratory distress syndrome (NRDS) and surfactant use, there was no significant difference in the demographics and other baseline clinical characteristics of the two groups. The incidence of BPD was higher in UU group than in non-UU group and there was statistically significant difference in severity of BPD (P = 0.044, 0.031). The infants had been followed up until they were 1 year old. Compared to infants in non-UU group, infants in UU group showed no significant differences in the rate of death of pulmonary infection in moderate and severe BPD infants, the same as the rates of BPD infants hospitalized again or hospitalized more than 2 times because of pulmonary infection or/and wheezing episode in the first year after birth.

Conclusion: Preterm infants infected with UU were more likely to have BPD than non-UU infants. BPD infants associated with UU infection were more severe than that in non-UU infants. Prognosis of BPD infants associated with UU infection was similar to that of the infants whose BPD was not associated with UU infection.