Cognitive outcome after bacterial meningitis

To evaluate long-term cognitive deficits in unselected patients with previously diagnosed meningitis and to compare these deficits to neurologic and psychopathologic impairment.

Twenty-two unselected patients (mean age 52.5 +/- 17.1 years) were examined neurologically, psychiatrically, and psychometrically 30 +/- 11 months after the acute stage of bacterial meningitis. Results of psychometric tests were compared with clinical long-term deficits. Psychometric tests were additionally applied on 17 healthy controls (mean age 49.2 +/- 14.2 years).

Neurologic or psychopathologic symptoms were found in 16 patients. Psychometrically, the speed of cognitive processes and psychomotor performance, concentration, visuoconstructive capacity, and memory functions were reduced significantly in patients as compared to controls. Verbal intelligence was less affected than performance efficiency. Patients with pneumococcal meningitis had significantly lower test results than patients with other pathogens. The psychometric test results were only slightly related with clinical findings of the follow-up examination.

Psychometric deficits are frequent after bacterial meningitis, and their relation with neurologic and psychopathologic symptoms is loose. The pattern of neuropsychologic impairment accentuates psychomotor slowing combined with memory disturbances, and resembles features observed in subcortical cognitive impairment.