The effect of 25-hydroxyvitamin D3 on the immune system.

AIM: To examine the effect of 25-OH vitamin D3 on the immune system in patients with nutritional rickets. METHODS: Fifty-three patients were included in our study between April 2002 and March 2004. Diagnosis of rickets was based on clinical, biochemical and radiological examinations. Cell surface markers (CD), complement factors (C), and immunoglobulin (Ig) levels were determined to find out any relationship between rickets and immune system deficiency. RESULTS: Among the causes of admission to hospital, fever (66%) and coughing (62.2%) were the most frequent. Pneumonia was accompanied by rickets in 47.1% of the cases. Plasma CD4 levels before the treatment were higher than those in the post-treatment period, whereas CD20 and CD56 levels were lower. CONCLUSION: B cell and natural killer cell reduction which occur because of vitamin D deficiency may contribute to the development of pneumonia and other infections in patients with nutritional rickets.