Epidemiological features and chemotherapy of community-acquired respiratory tract infections.

The epidemiology of community-acquired respiratory tract infections (RTI) is reviewed with emphasis on acute pharyngitis, otitis media, sinusitis, epiglottitis and pneumonia. The numerical importance of upper respiratory tract infections is stressed and their economic impact discussed. Community-acquired pneumonia, although less common, is a more serious infection with a frequent requirement for hospitalization. The heterogeneous microbial aetiology of RTI is stressed, together with the impact this has on chemotherapeutic choice. The latter is likely to remain largely empirical and based on the prevalence of identified pathogens, spectrum of activity and the pharmacokinetic behaviour of the selected agents. The increasing frequency of resistance among respiratory pathogens, notably Haemophilus influenzae, and to a lesser extent Streptococcus pneumoniae, together with the high incidence of beta-lactamase production among Branhamella catarrhalis is of concern. In addition, the issue of beta-lactam inactivation by commensal bacteria suggests that chemotherapeutic strategies for the control of community-acquired respiratory tract infection might justifiably be reconsidered.