We describe the case of a patient with a history of resistant asthma who presented with subacute neuropathy, hypereosiniphilia and central nervous system involvement; these findings were consistent with allergic granulomatous angiitis (Churg-Strauss syndrome). Although cutaneous biopsy prompted the diagnosis, the cases reported suggests that clinical, biological and histological data are all essential for the diagnosis. We emphasize that an early recognition of this syndrome may be important, since appropriate therapy may lead to recovery or influence favorably at least long term survival.