Rapidly progressive Creutzfeldt–Jakob disease in patients with Familial Mediterranean Fever

Background: The largest cluster of familial Creutzfeldt–Jakob disease (fCJD) exists in Jews of Libyan origin. Familial Mediterranean fever (FMF) is an inflammatory disease also common in this population. Objectives: We hypothesized that FMF, as a pro‐inflammatory condition, may affect the course of CJD. Methods: Three hundred and seventy‐two consecutive patients diagnosed clinically and genetically as CJD were included in the study. Two hundred and thirty‐six had fCJD, and 136 had sporadic disease (sCJD). Review of the patient’s records revealed three patients with FMF–CJD co‐morbidity. In addition, 50 DNA samples of patients with CJD were genotyped as homozygote, heterozygote, and non‐carriers of the FMF mutation. The demographic and clinical variables of the groups were compared. Results: The three patients with FMF had an earlier age of onset and significantly shorter disease duration than the patients without FMF. Heterozygote carriers did not differ in disease onset and duration from patients without FMF. Conclusions: The shorter disease duration of CJD patients with FMF may indicate the importance of pro‐inflammatory factors in the disease.