Low plasma vitamin D levels in patients with familial Mediterranean fever.

Familial Mediterranean fever (FMF) is an autosomal recessive, inherited autoinflammatory disease characterized by recurrent, self-limited attacks of fever and inflammation of serosal surfaces. There is an explosion of the data regarding inflammatory markers in FMF and clinical effects of chronic inflammation on the disease presentation. Vitamin D (vit D) is the common denomination of a group of sterols with a crucial role in phospho-calcium metabolism. There are some data about the importance of vit D in the initiation and propogation of a range of autoimmune diseases. The aim of the present study was to determine whether vit D deficiency is present in patients with FMF compared with healthy individuals. The study group included 99 patients with diagnosis of FMF attended to our outpatient Rheumatology and Nephrology Clinics of Atatürk Education and Research Hospital. The control group comprised 51 age- and sex-matched healthy people selected from hospital staff. Serum baseline 25-hydroxy vit D levels were measured by HPLC method using an Agilent 1100 Liquid Chromatograph. We found significantly lower serum 25-hydroxy vit D levels among FMF patients compared with matched controls and a high prevalence of vit D deficiency. This study demonstrated that vit D deficiency is frequent in patients with FMF than the healthy controls. It is convenient to look for vit D deficiency and to correct vit D nutritional status in FMF patients.