Kikuchi disease-associated Mollaret meningitis with MEFV gene mutation successfully treated with colchicine

Background: This case report aims to present a case of Mollaret meningitis caused by Kikuchi disease, an uncommon benign inflammatory disorder, thereby highlighting a novel etiology for Mollaret meningitis. Additionally, it discusses colchicine as a new potential treatment option for Kikuchi disease. Case presentation: A 41-year-old Japanese woman presented with fever and headache. She had nuchal rigidity and bilateral cervical lymphadenopathies. Her past medical history included multiple episodes of aseptic meningitis and cervical lymphadenopathy for more than twenty years. Lumbar puncture showed increased lymphocytes and IL-6 level and pathognomonic Mollaret cells. Excisional lymph node biopsy revealed histiocytic necrotizing lymphadenitis, confirming the diagnosis of Kikuchi disease. Subsequently, her recurrent Kikuchi disease was successfully treated with colchicine. Furthermore, genetic analysis of the MEFV gene revealed heterozygous P369S/R408Q mutation in exon 3. Conclusion: Mollaret meningitis can be caused by Kikuchi disease, and recurrence of both may be suppressed by colchicine.