The influence of vitamin D administration on the clinical presentation, body mass index, and osteoprotegerin (OPG) level in a sample of Egyptian children with familial Mediterranean fever

Abstract

Abstract Background Familial Mediterranean fever (FMF) is autosomal recessive chronic disease represents by recurring attacks of polyserositis, fever, and joint pain. Vitamin D deficiency in FMF children has been recently mentioned in literature and linked to delayed physical growth. Osteoporosis in FMF patients can be linked to low levels of vitamin D, too. Osteoprotegerin (OPG) might be used as an indicator for osteoporosis. Therefore, this work aimed to investigate the impact of vitamin D administration on clinical status, BMI, and bone mineral density represented by alterations in the OPG serum levels in a group of Egyptian children with FMF. This was a prospective longitudinal study carried out on 33 children, aged 4–16 years, with FMF cases. Patients were on colchicine 0.5–2 mg/day and received vitamin D3 oral drops 2800 IU/ml; each drop contains 100 IU in a dose of 600 IU/day for 6 months. The effect of vitamin D administration was evaluated clinically, anthropometrically and by assessment of serum vitamin D and osteoprotegerin at baseline and 6 months later. Results Serum vitamin D levels were below the normal range before intervention and showed significant improvement (p < 0.001) 6 months after intervention. Significant increase in both BMI Z scores (p < 0.05) and OPG serum levels and improvement in the clinical status as illustrated by significant decrease in the number of cases with fever, arthritis, and abdominal pain and significant decrease in the frequency and duration of the attacks (p < 0.001). Conclusion Our results intensely indicate that vitamin D supplementation improved the clinical condition, BMI, and bone mineral density in children with FMF.