Partial Body UV Exposure in Chronic Kidney Disease and Extrarenal Vitamin D Metabolism.

BACKGROUND/AIM: Exposure of the skin to sunshine is the major natural source of vitamin D. In order to imitate this natural production of vitamin D for patients with chronic kidney disease, hemodialysis patients were exposed three times a week to radiation of the front part of both legs to normalize the vitamin D status.

PATIENTS AND METHODS: Partial body UVB irradiation was performed during the routine dialysis session. Twenty-two patients took part, with a mean age of 61.7 (range=35-81) years.

RESULTS: Serum levels of 25(OH)D3 and 1,25(OH)2 D3 increased into the mid normal range. Intact parathyroid hormone decreased by 25% and osteocalcin by 45%. 24-Hour blood-pressure monitoring demonstrated decreases in systolic and diastolic blood pressure.

CONCLUSION: Partial body exposure to UVB radiation normalized not only the serum level of 25(OH)D3 , but also that of 1,25(OH)2 D3 , which resulted in a significant decrease in parathyroid hormone, osteocalcin levels, and also in blood pressure. Sunshine imitating UVB exposure utilizes the capacity of the skin to convert extrarenally vitamin D3 to 25(OH)D3 and 1,25(OH)2 D3 .