[Incidence of deep respiratory tract infections].

The distribution of respiratory tract infections (RTI) among the general population is not uniform. The incidence in neonates and the elderly (older than 65) is 2 to 3 times higher than that in adults. Examinations to determine the responsible pathogen are conducted in less than 1% of cases of RTI. The overall incidence of Haemophilus influenzae and Streptococcus pneumoniae in hospitalized patients amounts to 13 to 27%. The incidences of Staphylococcus aureus, Klebsiella and Pseudomonas aeruginosa in intensive care units are approximately 20% each. The management of the disease should be based on an aetiological diagnosis, and must take the individual patient's condition into account. Examination of the sputum or bronchial rinsing fluid is still the most reliable form of diagnosis, however, a sufficient number of quantitative methods must be applied. In hospitalized--and especially intensive care--patients these methods are often successful in isolating H. influenzae and pneumococci which we cannot afford to ignore as pathogens.