Pneumococcal meningitis in adults.

A retrospective study was conducted to examine the clinical features and outcome of 31 adult pneumococcal meningitis patients during the years 1981-92. The incidence was 1.0/100,000 adults/year. The case fatality rate was 16% (5/31), and in patients older than 70 years, 33% (3/9). Sequelae were seen in 29% (7/24), mostly otoneurologic symptoms. In 27/28 bacterial isolates the serotypes found were included in the 23-valent unconjugated polysaccharide vaccine in current use. All 28 isolates were fully sensitive to penicillin. 49/51 non-meningitis blood isolates had MIC values < or = 0.06 mg/l, 2 isolates had MIC values of 0.125 mg/l and 0.25 mg/l, and 50/50 were serotypes included in the 23-valent vaccine. Pneumococcal meningitis is a disease causing considerable mortality and morbidity. The relatively low case fatality rate found in the present study may be due to the patients' good health prior to admission, rapid specific microbiological diagnosis, absence of penicillin-resistant pneumococci among the meningitis strains, and immediate institution of specific and supportive therapy.