Cerebellar infarction as the initial presentation of IgG4-related disease.

Although IgG4-RD has CNS manifestations, cerebellar involvement has only been reported in three cases. Our patient presented with cerebellar symptoms, several cerebellar infarcts were evident on the brain MRI, and CT abdomen revealed retroperitoneal tumor. Endoscopic biopsy confirmed IgG4-RD. Steroids are the first-line therapy for IgG4-RD, but our patient was lost to follow-up before treatment.