Vitamin D levels in children with familial Mediterranean fever

BACKGROUND: This study aimed to determine whether vitamin D deficiency is more common in children with familial Mediterranean fever (FMF) than in healthy individuals. METHODS: The study group consisted of 100 patients diagnosed with FMF and 50 healthy children. Serum baseline 25-hydroxyvitamin D levels and other related parameters were evaluated. RESULTS: The mean (standard deviation [SD]) vitamin D levels in patients with FMF and healthy controls were 24.78 (8.35) and 28.70 (11.70) ng/mL, respectively. Patients with FMF had significantly decreased vitamin D levels compared with those in healthy controls (P = 0.039). Vitamin D levels were similar in patients with FMF with different MEFV mutations (P = 0.633). Age was significantly correlated with vitamin D levels (r = −0.235, P = 0.019). In addition, a negative correlation between parathyroid hormone and vitamin D levels was detected (r(s) = −0.382, P < 0.0001). CONCLUSION: This study demonstrated that vitamin D levels are lower in children with FMF than in healthy controls. We speculate that vitamin D levels should be carefully examined, and nutritional supplementation may be required in patients with FMF. Further studies with larger patient populations are needed to confirm the frequency of vitamin D deficiency in patients with FMF.