Prevalence of Chlamydia pneumoniae antibodies in Hungary.

Investigation of Chlamydia pneumoniae (TWAR) antibodies in paired sera of 120 patients with various respiratory diseases revealed a prevalence of 4.2% of IgG seroconversion. IgG antibody without seroconversion was found in 83.3%. Sera of ten patients showed titers as high as 512-1024 or above. Children with no respiratory disease and blood donors in Budapest had specific IgG in 46.5% and 75.2% respectively. Prevalence of IgG antibody in children from the rural areas of Hungary was about 50% lower than in children in the capital. The high prevalence of persistent IgG, indicating earlier infection, suggests that Chlamydia pneumoniae infection may be endemic in Budapest. The small number of the serologically confirmed acute infections in hospitalized patients with pneumonia leads to the conclusion that the majority of patients with chlamydial pneumonia responds to the therapeutic regimen administered by the general practitioner and referral to hospital rarely becomes necessary.