It has always been thought that most cases of acute respiratory infections (ARI), acute bronchitis and laryngotracheitis are caused by viruses and do not require antibiotics. However, more and more information has recently appeared on the role of “atypical” bacterial pathogens (M. pneumoniae, C. pneumoniae) in the etiology of these infections, especially in young people without concomitant pathology in children. The drugs of choice in the treatment of infections likely caused by "atypical" pathogens (chlamydia and mycoplasmas) are macrolides.

A study by S. Esposito et al. Considered whether M. pneumoniae and C. pneumoniae can cause acute respiratory infections in children with recurrent acute respiratory infections, and whether specific antibiotic therapy improves the condition of patients with acute disease and reduces the incidence of relapse. The study involved 353 children aged 1 to 14; the control group consisted of 208 healthy children. Patients were randomized to receive azithromycin (10 mg / kg / day 3 days a week for 3 weeks) in combination with symptomatic therapy, or only to receive symptomatic therapy.

Acute infection caused by M. pneumoniae and / or C. pneumoniae was diagnosed if the child had a marked increase in the titer of specific antibodies during a test in sera and / or pairs of bacterial DNA was detected in the nasopharyngeal aspirator.

Infections caused by "atypical" pathogens were diagnosed in 54% of patients (compared to only 3.8% in healthy individuals, p less than 0.0001). A short-term clinical effect (more than a month) was noted much more often in patients receiving azithromycin in combination with symptomatic therapy than in children receiving symptomatic therapy only, however, the differences were not statistically significant only in the group of patients infected with "atypical" pathogens. At the same time, a long-term clinical effect (more than 6 months) was significantly more often observed in patients who received azithromycin in addition to symptomatic treatment, than the infection in these patients was caused by "atypical" pathogens or other pathogens.

The study authors suggest that "atypical" bacteria may play a role in the development of recurrent respiratory tract infections in children, and long-term treatment with azithromycin can significantly improve the course of acute episode and reduce the risk of subsequent relapses.