Childhood Familial Mediterranean Fever in the United States: Spectrum of Clinical Phenotypes and MEFV Genotypes in a Cohort From Southeast Michigan.

Abstract

The aim of this study was to report the spectrum of Familial Mediterranean Fever (FMF) in children living in Southeast Michigan. We reviewed prerecorded data in medical records of FMF patients. Statistical analysis of the data included Fisher exact test, Pearson χ2 procedure, parametric independent samples t test, and parametric analysis of variance using SPSS Version 29.0, IBM Inc. The study included 29 males and 21 females. The mean age at presentation was 4.63 ± 3.66 years, and the mean time to diagnosis was 2.1 ± 2.18 years. A slight majority presented in the first 3 years of age (54%). Family history of FMF was reported in only 58% of patients. Clinical manifestations included fever (84%), gastrointestinal (84%), musculoskeletal (64%; including chronic arthritis, sacroiliitis, and nonbacterial osteomyelitis), chest (28%), cutaneous (14%), and other manifestations (16%). Fever without other manifestations was reported only in patients presenting at ≤3 years of age (p = 0.016), whereas older patients reported more gastrointestinal manifestations (p = 0.04). Reported MEFV variants included p.M694V (n = 26), p.V726A (n = 23), p.M694I (n = 13), and others (n = 10). Homozygote and compound heterozygote patients had more gastrointestinal manifestations (p < 0.001), whereas fever was more common in the heterozygote patients (p = 0.04). The mean follow-up period was 5.34 ± 4.13 years with no renal disease. We report the largest childhood FMF cohort in the United States. A negative family history should not preclude consideration of FMF as a cause of periodic fever. Recurrent fever can be the only manifestation, particularly in young patients with FMF. The absence of fever and chronic progressive musculoskeletal manifestations can uncommonly occur.