RESUMEN
The clinical and laboratory characteristics of bacterial meningitis in subjects over 59 years-old were evaluated to establish variables related to prognosis. All patients with clinical and laboratory findings of acute meningitis were included. Sixty-four episodes in 64 patients were registered. S.pneumoniae was responsible for 19 cases (27.5 percent); L.monocytogens - 3; S.aureus -1; S.bovis - 1; S.agalactie - 1 and Corynebacterium jeikeium - 1. Gram negative bacilli caused seven cases; two cases were due to N.meningitidis and one to H.influenzae. In 50 percent of the cases no microorganisms were isolated. The main symptom was fever (67.8 percent). Headache and neck rigidity were absent in about one-half of the cases and the predominant symptoms were psychomotor agitation, stupor or coma. The presence of concomitant diseases, such as diabetes mellitus (26.6 percent) and pneumonia (17.2 percent), were common. The mortality was high (51.5 percent). This poor prognosis was related to L.monocytogens (100 percent), Gram negatives rods (83 percent) and S.pneumoniae (58 percent). The univariate analysis showed that absence of headache (p=0.002), presence of coma (p=0.04), pneumonia (p=0.01) and immunocompromised status (p=0.01) were associated with risk of death. The type of the microorganisms isolated in the elderly patients with meningitis were often unusual ones. The clinical symptoms were minimal and in many cases, the only clinical presentation was change in mental status. Poor prognosis was observed in spite of intensive care. A high index of suspicion for miningitis while caring for elderly with changes in mental status must be maintained to avoid delays in initiating appropriate therapy.