[Causes of encephalopathy: descriptive study at Abidjan (Cote-d'Ivoire)].

Objective: Assess the etiology and course of cases of encephalopathy seen in the neurology department of the Cocody University Hospital in Abidjan (Côte-d'Ivoire), a city of more than three million inhabitants.

Methods: Retrospective analysis of patients admitted to the hospital neurology unit from 1 December, 1998, through 31 December, 2000; with a lesion of the brain, brainstem, cerebellum or meninges. Lesions were either confirmed by computed tomography or clinically obvious; MRI was unavailable.

Results: Overall, 1011 subjects met the inclusion criteria: 58% were male; their median age was 45 years (range: 1 to 93 years); more than 40% were not working, and 92% had a medical history. The etiology was vascular (445), infectious (380) or undetermined (125); rare cases were degenerative (5) or traumatic (4). Of 35 cases of metabolic encephalopathy, half were associated with another etiology. Pathological confirmation of cerebral tumors (22) was unavailable. All cases of toxic encephalopathy (11) involved adults and alcohol. Global lethality was 26% and did not differ significantly according to whether or not the etiology was identified (26% vs 28.8%). Another 13% were lost to follow-up (left without discharge), and 61% patients recovered and were discharged after a median hospitalization of 12.5 days.

Conclusion: The proportion of cases with an undetermined etiology is worrisome. Better knowledge would be useful to develop indicators to evaluate improvements in the medical management of these diseases.