[Prevalence of Chlamydia pneumoniae in respiratory infections in children: an ambulatory diagnostic problem].

It has been recently suggested that Chlamydia Pneumoniae infection is a common finding among children with acute respiratory diseases. Chlamydia cell culture is difficult and time-consuming to perform. Polymerase chain reaction (PCR) is a more rapid but also more expensive technique used to identify Chlamydia in pharyngeal swab, but it can be performed only in few specialized laboratories. We tested a rapid enzyme immuno-assay to detect Chlamydia in 20 children with respiratory infections (mean age 3.29 years; male:female ratio = 12:8) and in 21 healthy children (mean age 4.70 years male:female ratio = 15:6). Prevalence of Chlamydia isolation from pharyngeal swab was very high in both patients and healthy children without a significative difference in the two considered groups (45% vs 42%, p = 0.8). Specific Chlamydia IgG antibodies were undetectable in all patients and healthy children. Nine out of 20 patients affected by acute respiratory disease were Chlamydia-positive and 11 out 20 were Chlamydia-negative: these two groups didn't differ in regard to clinical and laboratory features, whereas duration of symptoms was significantly longer in Chlamydia-positive patients (9.3 vs 5.5 days, p = 0.014). Our study suggests a high prevalence of Chlamydia pharyngeal swab positivity in both healthy and sick children. Diagnosis of Chlamydia infection was not feasible on the basis of the considered clinical and laboratory findings.