ESPE Abstracts

Introduction: Nephrotic syndrome (NS) is one of the most frequent glomerular pathological conditions seen in children. The International Study of Kidney Disease in Childhood (ISKDC) reported that 84.5% of children with idiopathic nephrotic syndrome (INS) had minimal-change nephrotic syndrome (MCNS). Complications of INS may arise as a result of the disease itself or secondary to treatment. The chief complications of NS are infection, followed by thromboembolic events. Other disease-associated complications include hypovolemic crisis, cardiovascular complications, acute renal failure and hormonal and mineral alterations (e.g. hypothyroidism, and bone disease).

Objective: To study the level of serum ionized calcium during the active stage and after remission in steroid-sensitive nephrotic syndrome (SSNS) patients and 25-hydroxyvitamin D₃ (25-OHD) and parathyroid hormone (PTH) during the active stage of the disease.

Subjects and Methods: Twenty children with first episode of SSNS attending Alexandria University children’s hospital were investigated, compared to 20 healthy children as a control group. Serum ionized calcium, serum 25-OHD, PTH, phosphorus, alkaline phosphatase (ALP) were measured during the active stage of the disease and serum ionized calcium was repeated after remission.

Results: Children with active SSNS had low ionized calcium and low serum 25-OHD levels, with high PTH, high phosphorus and low ALP levels versus controls. All patients had 25-OHD deficiency of which 80% were severely deficient. Both serum ionized calcium and 25-OHD had a significant negative correlation with PTH (r=− 0.655, P=0.002) and (r=− 0.575, P=0.008) respectively. Serum ionized calcium was negatively correlated to spot protein/creatinine ratio in urine (r=− 0.565, P=0.009). Levels of serum ionized calcium during the active stage of the disease were markedly lower than that after remission. However, both were significantly lower than the control group.

Conclusion: Children with SSNS are at risk of vitamin D deficiency and hypocalcemia, therefore further studies will be needed to prove the need of vitamin D supplementation to prevent the occurrence of possible complications, e.g. tetany or bone abnormalities.