Meningeal involvement in Wegener's granulomatosis confirmed and monitored by positive circulating antineutrophil cytoplasm in cerebrospinal fluid.

MRI and CSF investigations revealed meningeal involvement in a 29-year-old patient with biopsy-confirmed Wegener's granulomatosis. The intracranial manifestation of Wegener's granulomatosis was supported by the detection of pathologic circulating antineutrophil cytoplasm (c-ANCA) in the CSF. We monitored disease activity by c-ANCA measurement in the CSF. After repeated cycles of intrathecal administration of methotrexate and corticoids, progression of meningeal infiltration stopped, and CSF c-ANCA titers became negative.