Chlamydia trachomatis: A major agent of respiratory infections in infants from low-income families

Objectives: to determine the prevalence of lower respiratory tract infection (lrti) due to chlamydia trachomatis in newborn infants and to describe the clinical,laboratory,and radiological characteristics of the disease. methods: a cross-sectional study carried out over a 12-month period. all infants up to 6 months of age admitted consecutively at the centro pediátrico professor hosannah de oliveira of the universidade federal da bahia in salvador,brazil,and diagnosed with lrti according to clinical and/or radiological criteria were included in the study. c. trachomatis infection was diagnosed by the enzyme-linked immunosorbent assay (elisa) for the detection of igm-class antibodies. the prevalence of lrti by c. trachomatis was determined and the prevalence ratios for the infection and clinical or laboratory variables were calculated. results: one hundred and fifty-one infants were submitted to serology for c. trachomatis and 15 (9.9%) tested positive. chlamydial infection was found only in infants under 5 months of age,mainly in those aged under 2 months. three of the infants with c. trachomatis infection were born by cesarean section. conjunctivitis and eosinophilia had occurred in 33.3% of the cases. chest x rays were abnormal in 92.0% of cases. there was an association between c. trachomatis infection and the duration of hospitalization exceeding 15 days (p = 0.0398) and oxygen therapy (p = 0.0484). conclusions: there was a high prevalence of c. trachomatis respiratory infection in the population studied. the infection was associated with a more severe form of the disease,emphasizing the importance of testing pregnant women for this infection to avoid infection in the newborn infant. copyright © by sociedade brasileira de pediatria.