[Serologic diagnosis of severe non-bacterial pneumonia and acquired in the community]

The aim of this study was to evaluate the profitability of the serology, especially against Streptococcus pneumoniae and Chlamydia sp., in the community pneumonia with hospital admission.

Descriptive and retrospective study. One hundred fifty-five pair of sera of 129 patients adults and 26 patients with less of 15 years with pneumonia were analysed. Antibody against respiratory virus, Coxiella burnetii, Mycoplasma pneumoniae, Legionella pneumophila, Chlamydia sp. and S. pneumoniae were investigated.

The serology diagnosis was obtained in 58 patients (37.4%) (42 [32.6%] adults and 16 [61.5%] children; p = 0.006). The pneumonia most frequently detected was caused by M. pneumoniae (21 cases; 13.5%), followed by Chlamydia spp. (13, 8.4%), S. pneumoniae (8, 5.2%) and mixed infection in other 7 cases. Detection of antibodies against pneumococcus and Chlamydia sp. improved as a whole in 8.4% (from 29% to 37.4%), a 10.9% (from 22.5 to 32.6%) in adults and none case in children. Moreover, a major proportion of mixed infection and by syncytial respiratory virus in children (19.5 and 11.5%, respectively) versus adults (1.6 and 0%, respectively; p < 0.1) was observed.

With the detection of antibodies against Chlamydia spp. by indirect immunofluorescence and capsular polysaccharide pneumococcal by enzyme-immunoanalysis increased the etiologic diagnosis of the community pneumonia.