The etiology of neonatal pneumonia, complicated by bronchopulmonary dysplasia

Abstract.
BACKGROUND:
The frequency of bronchopulmonary dysplasia (BPD) in preterm infants with a “ventilator-associated” pneumonia (VAP) ranges between 7 to 50%. OBJECTIVE:To investigate the features of the etiological structure of neonatal pneumonia complicated by BPD, and to determine the sensitivity of pathogens to antibiotics.
METHODS: A retrospective chart review of 194 preterm infants with VAP, birth weight from 780 to 2820 g and gestational age from 27 to 37 weeks was conducted. A microbiological study of washings from the respiratory tract was conducted by standard qualitative and quantitative methods.
RESULTS: Respiratory tract infections caused by E. coli (with hemolytic properties), Enterococcus spp. (with hemolytic properties), Pseudomonas aeruginosa, Stenotrophomonas maltophilia, various types of mycoplasmas, Staphylococcus aureus, and Candida krusei were found 4– 13 times more frequent in preterm infants with BPD than in preterm infants without BPD and more mature infants with or without this complication. BPD developed 7– 11 times more frequent in preterm infants with prolonged VAP and change in pathogens than in preterm infants with VAP without change of agent. BPD developed 5– 7 times more frequent in preterm infants with the association of pathogens than in preterm infants with a monoinfection. Massive colonization of respiratory tract pathogens by 1– 3 days of life (lg4 colony forming units in 1 ml and above) was an unfavorable prognostic factor for the development of VAP, complicated by BPD.
CONCLUSION: The reduction in the frequency of BPD is might be possible with timeous and adequate antibacterial therapy of VAP.

*Corresponding Author: 

Maria Vasilievna Kushnareva, MD, Leningrad Prospekt, 45, Building 3, Apartment 262, Moscow, Russia, 125167. Tel.: +7 4991574457; +79165456968; Fax: +7 499 483 33 35; E-mail: mkuschnareva@mail.ru.