Efficacy and tolerability of azithromycin versus amoxicillin/clavulanic acid in acute purulent exacerbation of chronic bronchitis

Abstract

An open randomized trial was conducted in 142 hospitalized and out-patients with acute purulent exacerbation of chronic bronchitis to compare the clinical efficacy and tolerability of azithromycin (n = 69) and amoxicillin/clavulanic acid (n = 73). Azithromycin (500 mg) was administered as a single dose for three days and amoxicillin/clavulanic acid (amoxicillin 875 mg-clavulanic acid 125 mg) was given b.i.d. for 8 days (8.16 +/- 1.18). Before therapy and 24-48 hours after the end of treatment, sputum culture (by positioning five orthodontal swabs at the opening of salivary gland ducts after a washing of the oral cavity with sterile saline solution to avoid oral contamination), chest X-rays, arterial blood gas analysis, trials of respiratory functions and routine blood tests were performed. In the azithromycin group (69 patients) the efficacy rate was 67.6% (46 patients: 34 cured and 12 improved); in 22 patients (32.4%) the treatment failed; 1 patient was not evaluated because of no follow-up. The overall efficacy rate in the amoxicillin/clavulanic acid group (73 patients) was 97.3% (71 patients: 60 cured and 11 improved); in 1 patient (1.4%) the treatment failed and 1 patient was a drop-out for side effects. All pathogens isolated before treatment were susceptible to the antibiotics administered. At the end of treatment microbiological efficacy was 67.1% in the azithromycin group and 98.6% in the amoxicillin/clavulanic acid group. The tolerability was judged good in both treatment groups. Side effects were observed in 1 patient treated with amoxicillin/clavulanic acid (diarrhea), which imposed interruption of treatment, and in 2 patients from the azithromycin group (gastralgia and biochemical laboratory tests: renal function).(ABSTRACT TRUNCATED AT 250 WORDS)