Vitamin D deficiency in hemodialysis.

Sir,

The recent publication on vitamin D deficiency in hemodialysis is very interesting.[1] Bansal et al. concluded: “Vitamin D deficiency and insufficiency are universal in our hemodialysis patients, with severe vitamin D deficiency in two-third of patients.”[1] Indeed, the nutrient deficiency is an important problem in hemodialysis patients. However, the important question remaining is still on the exact pathophysiology of this disorder. The metabolic alteration can be an explanation for vitamin D deficiency among the hemodialysis patients.[2] Nevertheless, the vitamin D deficiency can be due to several etiologies including decreased intake, diminished absorption, or insufficient sunlight exposure. In fact, sunlight exposure is the main contributing source of vitamin D in human beings. The appropriateness of sunlight exposure among hemodialysis patients is little mentioned. The query is whether there is a proper recommendation for the hemodialysis patients to get appropriate sunlight exposure. In a recent report, it is noted that vitamin D deficiency was highly prevalent in the subjects with decreased sunlight exposure.[3] It is also confirmed that sunlight exposure increased the serum concentration of 25-hydroxyvitamin D in hemodialysis patients.[4]