Introduction: Adult non tuberculous primary bacterial meningitis (PBM) represents an important cause of morbidity and mortality in hospitals. The shortage of studies based on the population in Latin America provided the motivation for this work.
Aims: To determine the incidence of PBM in the captive population of our hospital and carry out a descriptive analysis of the cases detected.
Patients and methods: We performed an epidemiological study of the captive population (CP) of the hospital (an average of 85,200 patients in 11 years) and a retrospective descriptive examination of patients who had been admitted. The clinical histories of all patients over the age of 18 who had been admitted with PBM between 1 January 1988 and 31 December 1998 were studied.
Results and conclusions: A total number of 87 cases of primary bacterial meningitis were registered, of which 70 belonged to the CP. The overall gross rate of PBM incidence in the CP was 8.6/100,000 per year. The annual incidence rate, adjusted to the 1991 National Census on the Argentinean Population, was 5.4/100,000 per year, with a greater frequency between the ages of 70 and 79: 21/100,000 per year. Median age: 73 (lower quartile, 66; upper quartile, 78). Clinical manifestations included high temperatures (90%), consciousness disorders (87%), and a stiff neck (81%). The frequency with which it appeared remained constant over the 11 year period, without showing any seasonal variations. The most frequent etiological agent was pneumococcus (50%). No cases of PBM by Listeria were reported. Overall fatality during the stay in hospital was 23%, without any type of modification over the period we studied.