Brainstem Encephalitis: An Unusual Neurologic Complication of Kikuchi-Fujimoto Disease

Abstract Kikuchi-Fujimoto disease (KFD) is an uncommon, self-limiting histiocytic necrotizing lymphadenitis of unknown aetiology which commonly affects younger women, and displays a higher prevalence amongst Asians. It is characterized by non-specific clinical features of regional lymphadenopathy, fever, and night sweats, and is thus commonly mistaken for tuberculous infections, systemic lupus erythematosus, and lung or lymphomatous malignancies. Nodal biopsy is often helpful in demonstrating the classical findings of necrosis with karyorrhexis. Neurological complications have been sparingly reported, with KFD patients developing aseptic meningitis or meningoencephalitis, weeks to months after the onset of lymphadenopathy. KFD-related neurologic complications involving the brainstem were even rarer, and consequently present significant diagnostic challenges to physicians. Herein, we describe a patient who developed acute area postrema six months after the onset of KFD symptoms