Comparison of amoxycillin/clavulanate with amoxycillin in children and adults with chronic obstructive pulmonary disease and infection with Haemophilus influenzae

71 children and adults (median age 7 years) with chronic obstructive pulmonary disease in which ampicillin-sensitive Haemophilus influenzae were isolated from lower airway secretions were included in a single-blind study comparing amoxycillin/clavulanate and amoxycillin alone. The dosage of amoxycillin was 50 mg/kg/day given together with probenecid and divided in 3 doses. Duration of treatment was 14 days. Clinical and bacteriological examinations were performed at study entry and again immediately after the treatment period. A late bacteriological follow-up 1.5 months after entry was performed. 65 patients were eligible for analysis of clinical outcome, and no difference between the groups was found. Side-effects were mild at a frequency of 3% for either preparation. In terms of eradication of the initially isolated H. influenzae amoxycillin/clavulanate tended to be better than amoxycillin, although the difference was not significant (70% and 57%, respectively). In a subset of 33 patients with polymicrobial flora amoxycillin/clavulanate was significantly more effective than amoxycillin. However, amoxycillin/clavulanate did not significantly reduce the emergency of beta-lactamase producing H. influenzae during treatment, and thus offers no advantage over amoxycillin in patients with amoxycillin-sensitive H. influenzae. The combination should be reserved to patients with either polymicrobial flora or ampicillin-resistant H. influenzae.