[Tuberculous meningioma en plaque without extracerebral tuberculosis. A case report]

Tuberculosis continues to be an intensly extended disease in under developed countries in immunodepressed and immunocompetent persons. In the central nervous system tuberculous lesions are the most frequent cause of space occupying lesions.

We report the case of a young, immunocompetent woman from Guinea, currently living in Spain. Following a seizure, neuro imaging showed there to be a right frontal space occupying lesion. The characteristics of the MR images obtained were fundamental to the determination of the meningeal site of the lesion en plaque and to suggest the aetiology as being an infectious inflammatory process, although a meningioma could not be ruled out. The absence of signs of extracerebral disease, the localization and distribution of the lesion and lack of short term response to medical treatment, which covered the different diagnostic possibilities, made it necessary to do a diagnostic meningeal biopsy.

MR imaging is a great help in the diagnosis of tuberculous lesions of the central nervous system. The differential diagnosis between tuberculous pachymeningitis and meningioma, both in the form of plaques, is extremely difficult without obtaining a biopsy specimen. The finding of epithelioid granulomas with caseous necrosis and/or acid alcohol fast bacilli in the biopsy specimen is diagnostic of tuberculosis. A single meningeal lesion situated in the cortex but with no associated extracerebral disease causes considerable difficulty in diagnosis. Tuberculosis must always be remembered in view of the increasing number of immigrants from under developed countries.