RESUMEN
A 77-year-old man with a history of cigarette smoking had suffered from vertigo and depression repeatedly for twelve years. He gradually developed bradykinesia in the past half decade and fell down 3 times in the last half year. On admission, he presented with cerebellar ataxia and bulbar symptoms. Brain MRI showed atrophy in the cerebellum and brainstem. 123I-IMP SPECT showed hypoperfusion bilaterally in the cerebellum. Blood examinations showed various elevated inflammatory values and positive for HLA-B51. Cerebrospinal fluid (CSF) revealed aseptic meningitis and increased IL-6 levels. Therefore, we strongly suspected that he had chronic progressive neuro-Behcet's disease (CPNBD), clinically. Systemic mucocutaneous symptoms appeared 1 month after starting treatments. Pathological findings of his skin biopsy were consistent with Behcet's disease. It should be kept in mind that both positive HLA-B51 and increased CSF IL-6 levels have the possibility of containing important clues in the diagnosis of CPNBD.