Ureaplasma Urealyticum Tracheal Colonization and Respiratory Disease in Newborns

Abstract

BACKGROUND: Causality between Ureaplasma urealyticum (U) grown from tracheal cultures (TC) and bronchopulmonary dysplasia (BPD), pulmonary hypertension (PPHNB), and neonatal mortality has been proposed. We re-examined these relationships using a cohort design. MATERIALS & METHODS: We prospectively obtained TC from 377 mechanically ventilated infants delivered at University Hospital who were intubated an average of 23 days, and from whom we collected 783 TC (288 of them taken at birth and the rest weekly). Clinical and laboratory information was retrieved from medical records. RESULTS: Of the 377 infants, 54 (14%) had one or more positive TC for U during hospitalization. Of the 54 colonized infants, 45 (83%) weighed ≤ 1,250 g, 7 (13%) between 1,251 and 2,500 g, and 2 (4%) 2,500 g. One hundred and eighty four infants had birthweights ≤ 1,250 g. Forty-five (24%) of them were U positive and 139 (76%) were negative. Mean birthweight, gestational age, duration of mechanical ventilation, incidence and severity of BPD, and neonatal mortality were similar between the two groups. Forty infants diagnosed with PPHNB who were mechanically ventilated an average of 7 days provided 91 TC. Only 2 of these infants were U positive. Thirty-nine PPHNB patients survived and did not develop BPD. CONCLUSIONS: U. urealyticum tracheal colonization defined by serial TC is common among small, premature, mechanically ventilated infants. No association between this colonization and incidence or severity of BPD, neonatal mortality, and PPHNB was found. [Respir Care 1996;41(1):22-29]