Bone mineral density using dual-energy X-ray absorptiometry in children with nephrotic syndrome: a cross-sectional...

Children with nephrotic syndrome (NS) receive long-term steroid therapy and hence there is an increased risk of bone mineral disease. The objective of the study was to compare the bone mineral density (BMD) in children with NS with that of healthy age-matched controls by using Dual-energy x-ray absorptiometry (DXA) and its correlation with metabolic parameters.

A single-center cross-sectional study was conducted to assess the BMD using DXA scan in children aged 5-14 years with NS compared to age and gender-matched healthy children in a tertiary care center. Sixty-two children were included (31 with NS and 31 healthy children as controls), and BMD's were assessed using a DXA scan. Z-scores were calculated and correlated with biochemical parameters such as serum alkaline phosphatase, calcium, phosphate, parathormone, and vitamin D.

Low BMD was observed in almost 64.5% of children with NS. The mean BMD and height adjusted Z score were lower in children with NS than healthy children. The mean BMD/Z-score in NS and controls were-left femur neck (- 2.18 ± 1.49 vs - 0.461 ± 0.94), right femur neck (- 2.47 ± 1.54 vs - 0.50 ± 0.88), spine (- 1.72 ± 1.16 vs - 0.603 ± 0.80), respectively and these differences were statistically significant (p < 0.05). The correlation between cumulative steroid dose and BMD/Z-score was not statistically significant.

Children with NS had lower BMD and serum vitamin D levels than healthy children despite calcium and vitamin D supplementation, and they need periodic evaluation.