Purpose: In this study, we present clinical data from 16,000 familial Mediterranean fever patients. We also discuss the clinical manifestation of a subset of these patients and their potential symptom associations with other disorders.
Methods: Familial Mediterranean fever patients were confirmed using Tel-Hashomer criteria and were tested for the 12 most common mutations using the familial Mediterranean fever StripAssay. A total of 100 samples were selected, and their MEFV gene exons and intron junctions were completely sequenced.
Results: We observed that in children severe phenotypes with polyserositis, erysipelas-like erythema, splenomegaly, and vasculitis are associated with high penetrance of exon 10 mutations, particularly M694V. Several forms of arthritis were associated with familial Mediterranean fever, including acute mono/oligoarthritis in the lower extremities, destructive arthritis, ankylosing spondylitis, sacroiliitis, arthritis of the hip joint, and juvenile chronic arthritis. Severe life-threatening complications, such as adhesive intestinal obstruction, renal amyloidosis, and uncommon/rare symptoms were sometimes the only form of familial Mediterranean fever manifestation.
Conclusion: We suggest performing familial Mediterranean fever genetic testing for patients presenting with rare/uncommon symptoms also common in other disorders, to prevent misdiagnosis or delayed diagnosis. In our experience, the most effective patient management for familial Mediterranean fever was its rapid diagnosis through genetic testing, initiation of colchicine therapy, and promotion of attack prevention through counseling.