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

Abstract

Objectives: The aim of this study was to report the spectrum of Familial Mediterranean Fever (FMF) in children living in Southeast Michigan.

Methods: We reviewed prerecorded data in medical records of FMF patients. Statistical analysis of the data included Fisher exact test, Pearson χ 2 procedure, parametric independent samples t test, and parametric analysis of variance using SPSS Version 29.0, IBM Inc.

Results: 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.

Conclusions: 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.