Clinical Comparative Study of Azithromycin versus Erythromycin in the Treatment of Acute Respiratory Tract Infections in Children

Summary

The efficacy and tolerability of azithromycin and erythromycin in the treatment of acute respiratory tract infections in children were compared in an open, multicenter, randomized trial. A total of 151 children, aged from 2 months to 14 years, suffering from upper airways infections (60), or lower respiratory tract infections (91), were randomized to be treated either with azithromycin, 10 mg/Kg/day per os once daily for 3 or 10 mg/Kg/day 1 and 5 mg/Kg/days 2-5 (77 patients) or with erythromycin, 50 mg/Kg/day thrice daily for at least 7 days (74 patients). The two treatment groups did not significantly differ as to sex, age, weight, type and severity of infection, and infecting pathogens.

Clinical evaluation was performed prior to therapy, on treatment days 1, 3, 5 and 7, and on day 10. Microbiological and laboratory assessment were carried out at baseline and after the end of therapeutic course. Chest X-ray and serologic assays for Mycoplasma pneumoniae infection were obtained in patients suspected to have lower respiratory tract infections. At the end of therapy, clinical cure was achieved in 73 out of 77 patients (94.8%) in the azithromycin group, and in 60/72 evaluable subjects (83.3%) in the erythromycin group. A significantly more rapid remission of several illness-related signs and symptoms was observed in patients treated with azithromycin. A total of 75 bacterial pathogens were isolated at baseline microbiological examination; at the end of the therapeutic course bacteriological eradication was obtained in 34/34 cases (100%) treated with azithromycin, and in 40/41 children (97.5%) treated with erythromycin. Both study drugs were well tolerated; transient, mild to moderate side-effects were reported in 6.5% of patients treated with azithromycin, and in 9.5% of subjects who received erythromycin. Only 2 children of the erythromycin group withdrew from the study due to adverse effects (vomiting). Significantly abnormal laboratory test values were observed in only one child treated with azithromycin (transient rise in serum AST-ALT values), and returned to normality at follow-up.

In conclusion, azithromycin once daily for 3-5 days is as safe and effective as erythromycin thrice daily for at least 7 days in the treatment of community-acquired respiratory tract infections in infants and children; no statistically significant difference was found between the two treatment groups as to overall clinical and bacteriological efficacy, and systemic tolerability. The significant advantage of a low-dose therapeutic course of azithromycin is made possible by the enhanced antimicrobial potency and the favorable pharmacokinetic properties of this novel macrolide derivative.