Increase in bronchopulmonary infection due to Branhamella catarrhalis

In a six month prospective study during the winter Branhamella catarrhalis was isolated from the sputum of 63 patients with symptoms of bronchopulmonary infection: 49 isolates were in pure culture and 14 were with another pathogen, Haemophilus influenzae being the commonest (found with 10 of the 14 B catarrhalis isolates). Of 36 patients infected in the community, 26 required admission to hospital. The remaining 27 patients were infected while in hospital. Forty four of the 63 isolates produced beta lactamase; 26 of these had been acquired in the community. As a result 29 patients were treated inappropriately with ampicillin and did not respond to this treatment. beta Lactamase produced by B catarrhalis may also protect other pathogens normally susceptible to beta lactam antibiotics. Most patients had chronic lung diseases or lung cancer, but three otherwise healthy patients who did not smoke developed bronchitis. B catarrhalis contributed to the death of five patients. A survey of the antibiotic prescribing habits of the referring general practitioners together with the sensitivity results of B catarrhalis suggest that changes in antibiotic prescribing habits in the community may be responsible for the increase in B catarrhalis infection.