Vitamin D deficiency in children with Chronic Kidney Disease-Mineral Bone Disorder (CKD-MBD) and factors affecting response to cholecalciferol therapy: A quasi-experimental study from low-middle income setting

Chronic Kidney Disease-Mineral Bone Disorder (CKD-MBD) is characterized by hypocalcemia, hyperphosphatemia and abnormal vitamin D (VD) metabolism resulting in high parathyroid hormone secretion. The objective of the study was to determine VD status in children with CKD-MBD and the effect of cholecalciferol therapy in these children.

This quasi-experimental study was conducted at the Department of Pediatrics, National Institute of Child Health, (NICH), Karachi, during 2016-2017. The sample size was 81. VD deficient and insufficient patients were supplemented with oral cholecalciferol and response was assessed by vitamin D (25-OHD), serum calcium, phosphorus and parathyroid hormone (PTH) levels after 3 months.

Fifty (61.70%) were males and 31(38.30%) females. The mean age was 8.06±4.01 years with a majority (70.37%) above 5 years. The mean height was 125.85±25.38 centimeters. The mean disease duration was 2.37±1.38 years. The majority of patients had CKD stage III (56.80%), followed by stage IV (24.7%) and stage II (18.5%). Most patients were insufficient (85.2%) and others were deficient (14.8%) in VD status. The mean serum 25-OHD, PTH, Calcium and Phosphorus levels before therapy and after supplementation were 16.98±4.24 ng/ml and 39.34±9.08 ng/ml, 105.11±26.40 pg/ml and 90.82±24.92 pg/ml, 8.92±0.77 mg/dl and 9.32±0.76 mg/dl, 3.61±0.37 mg/dl and 4.07±0.38 mg/dl, respectively. The P-value was <0.05.

VD supplementation has increased serum calcium and serum 25-OHD levels and suppressed phosphate and PTH levels, which may halt the MBD and thereby improve the outcome of CKD. Therefore, early supplementation with cholecalciferol therapy is recommended for all children with CKD.