Vitamin D in Rheumatic Diseases: State of the Art

Introduction: The classical role of vitamin is the regulation of calcium levels in the blood and in the interstitial fluids. In the last years the role of vitaminD has been studied in other diseases and in autoimmunity. Aim: To revise the role of vitamin D in rheumatic diseases. Results: Studies have suggested a potential role of vitamin D in autoimmune system and a possible negative correlation with disease activity in SLE patients that present many risk factors predisposing to low vitamin D serum levels. Patients with CTD may present low levels of vitamin D and it may relate to the development into a specific CTD. Patients with SSc present skin fibrosis that may influence serum levels of vitamin D; in RA a negative correlation between low levels of vitamin D and disease activity and bone loss has been suggested. The link between vitamin D and JIA is still discussed, however some studies showed a similar correlation than in RA. In Kawasaki disease low levels of vitamin D seem to have a role in coronary complications. Conclusions: Low levels of vitamin D have been detected in rheumatic diseases and a negative link between vitamin D deficiency and disease activity has been suggested.