A Randomized Controlled Trial to assess the effect of Vitamin D deficiency and supplementation on Bone Mineral Density in steroid sensitive nephrotic syndrome

Steroid sensitive nephrotic syndrome (NS) is a common disease affecting Indian children. The majority of affected patients have multiple relapses over many years and require repeated and long term steroid courses. Steroid toxicities like osteoporosis have been well described in this condition and may cause long term morbidity, even after the NS has resolved. Reduction in bone mineralisation has been reported to occur early, within 2 to 3 months of steroid therapy. Unfortunately in the majority of patients steroid treatment cannot be avoided.

During NS episodes, there is loss of Vitamin D binding protein along with albumin in the urine. Patients have been shown to have low levels of 25 hydroxycholecalciferol in this condition. Correction of this associated hypovitaminosis D may improve bone health in this disease and reduce degree of osteoporosis.

In addition, low Vitamin D stores have been associated with inflammatory and infective conditions. Infections are the commonest precipitants of relapses in NS. Thus correction of hypovitaminosis D may reduce relapse rates in pediatric NS.

In this RCT, patients with NS relapse are recruited, and randomised into intervention and control groups. The intervention group receives Vitamin D and calcium supplements in the attempt to optimise serum 25hydroxycholecalciferol levels. Subsequently over a 6 month period, the changes in serum 25hydroxycholecalciferol, bone mineral density and bone mineral content as well as relapse rate is analysed and compared with the control group. Monitoring is performed for any adverse effects of Vitamin D therapy, such as hypercalcemia, hypercalciuria and nephrocalcinosis.