Reduced 25-OH vitamin D in patients with autoimmune cytopenias, clinical correlations and literature review

Vitamin D deficiency is widespread in Western Countries and has been found related to autoimmune and hematologic disease incidence and clinical course. We evaluated vitamin D levels, vitamin D receptor (VDR) and T helper (Th)1, Th2 and Th17 immunomodulatory cytokines in patients with immune thrombocytopenic purpura (ITP, N = 44), primary autoimmune hemolytic anemia (AIHA, n = 35), Evans' syndrome (n = 5) and chronic idiopathic neutropenia (ClN, n = 19) and also tested vitamin D effect on the in vitro production of anti-erythrocyte autoantibodies. 25-OH-vitamin D levels were significantly lower and vitamin D receptor higher in patients than in controls. Among ITP cases, those with very low vitamin D levels displayed reduced platelet counts, irrespective of the bleeding history. In AIHA patients, LDH values negatively correlated with vitamin D levels in mixed forms, and reticulocyte counts were positively related with vitamin D. Considering treatment, AIHA patients who had been treated with 2 therapy lines or more showed lower mean 25-OH-vitamin D levels than those untreated or treated with one line of therapy only. IL-6, IL-10, IL-17 and IFN-gamma levels were higher in patients versus controls, whereas TNF-alpha. was significantly reduced. Finally, vitamin D at concentrations of 10, 20, and 40 ng/mL reduced the in vitro production of anti-erythrocyte autoantibodies both in pokeweed-stimulated and unstimulated cultures, In conclusion, vitamin D is reduced in autoimmune cytopenias and correlate with disease severity, supporting its possible protective role against the development of autoimmunity. Literature review showed vitamin D deficiency reports both in onco- and in non onco-hematologic diseases with a relationship with disease severity/activity in myeloid and lymphoid neoplasms, as well as in sickle cell disease. Supplementation has produced weak results in autoimmune and hematologic diseases, and further studies are needed. (C) 2016 Elsevier B.V. All rights reserved.