Familial Mediterranean Fever After Cord Blood Transplantation for Familial Hemophagocytic Lymphohistiocytosis.

Familial Mediterranean fever (FMF) is a hereditary autoinflammatory disorder accompanied by periodic fever and sterile serositis. We report a 5-year-old boy with FMF, who underwent second unrelated cord blood transplantation (CBT) for recurrent familial hemophagocytic lymphohistiocytosis. Periodic attacks of fever and abdominal pain started 6 months after CBT. He was diagnosed with FMF according to the Tel-Hashomer criteria and treated successfully with colchicine. Genetic testing showed heterozygous p.E148Q mutation in the MEFV gene from both donor and recipient cells. Several CBT-related factors including use of an immunosuppressant can potentially be involved in the pathogenesis of FMF in our patient.