Clinical Characteristics Of Ureaplasma Urealyticum Respiratory Tract Infection In Preterm Neonates

Research background:Ureaplasma urealyicum(UU) was the most common organism that causes infection in the human gential tract.It affected pregnancy outcome such as infertility, chorioamnionitis,spontaneous abortion,and preterm Labor.It could be vertical transmitted from infected females to the fetus and induced host immunological response of neonates and sequential pneumonia,bronchopulmonary dysplasia(BPD),bacteremia, infection of the central nervous system and other systemic diseases.It was well known that UU was the major organism that leads to infection of pregnant women and fetus in perinatal period.However,the clinical characteristics of ureaplasma urealyicum respiratory tract infection in preterm neonates in Chinese neonatal intensive unit was not systematically studied.Objective:This study was to analyze the clinical characteristics of ureaplasma urealyticum respiratory tract infection in premature neonates,and to find the fators that would increase survival rate and improve outcome of preterm neonates in perinatal period. Methods:It was a prospective study to evaluate the premature neonates＜32 weeks gestation age with mechanical ventilation,who had low respiratory tract secretion tested for ureaplasma urealyticum DNA by the polymerase chain reaction in the first 48 hours of life.The clinical characteristics were analyzed and summarized.Result:1.Ureaplasma urealyticum respiratory tract infection rate was 31.40%.Positive group had higher incidence of premature rupture of membranes(60.5%vs 10.8%), spontaneous vaginal delivery(92.1%vs 68.7%),and lower gestational age(29vs 31weeks)(P＜0.05).2.Positive group had higher total white cell and neutrophil counts during the first 2 weeks of life(P＜0.05).3.Positive group had lower FIO₂ with mechanical ventilation(21%vs 30%),higher rate of chest radiographic abnormalities(36.8%vs 9.6%) and longer days with oxygen therapy(8.5 vs 4days)(P＜0.05).4.Positive group had increased incidence of BPD(15.8%vs 7.2%)(P＜0.05).5.Infection with UU-DNA＞2.5×10⁴copies would had longer days with oxygen therapy(10 vs 6days) and increased incidence of BPD(25%vs 0%)(P＜0.05).Conclusions:1.Ureaplasma urealyticum respiratory tract infection in preterm neonates would had increased incidence rate of premature rupture of membranes,spontaneous vaginal delivery and lower gestational age.2.Ureaplasma urealyticum respiratory tract infection would have higher total white cell and neutrophil counts during the first 2 weeks of life.3.Ureaplasma urealyticum respiratory tract infection would have higher rate of chest radiographic abnormalities. 4.Ureaplasma urealyticum respiratory tract infection in preterm neonates would had lower FIO₂ with mechanical ventilation,longer days with oxygen therapy and increased incidence of BPD.5.UU-DNA＞2.5×10⁴ copies would predict unfavourable outcome.