Markers of Bone Metabolism in Children with Nephrotic Syndrome Treated with Corticosteroids

Abstract

The aim of the study was to assess bone mineral density, bone metabolism markers, and vitamin D level in children with idiopathic nephrotic syndrome in the course of 1-year observation. Twenty five children with nephrotic syndrome aged 5-17 years were enrolled into the study. The median number of relapses was 6 (range 1-22). All patients were treated with prednisone and vitamin D (800 IU/day). Bone mineral density of total body (TB-BMD) and lumbar spine (L-BMD), evaluated by dual energy X-ray absorptiometry (DXA) expressed as Z-score, and serum calcium, phosphorus, parathormone (iPTH), alkaline phosphatase (ALP), bone alkaline phosphatase (BAP), osteocalcin (OC), albumin, creatinine, 25(OH)D3, 1,25(OH)2D3 and urine calcium/creatinine ratio (uCa/Cr) were evaluated at the enrollment visit and after 1 year of therapy. After 1 year significant decreases of TB-BMD Z-score (from -0.24±1.34 to -0.74±1.31, p<0.05) and 25(OH)D3 serum level (from 31.7±16.3 to 23.7±9.3; p<0.05) were observed. No other appreciable differences were found. At the study onset, negative correlations were found between L-BMD Z-score and serum ALP, BAP, and phosphorus and between TB-BMD Z-score and urine uCa/Cr. After 1 year, L-BMD Z-score correlated negatively with serum BAP and OC, and positively with serum 25(OH)D3. Multivariate analysis showed that BAP was the strongest predictor of L-BMD Z-score (beta=-0.49; p<0.05). We conclude that children with nephrotic syndrome treated with corticosteroids are at risk of bone mass loss. Serum BAP concentration seems to be a good indicator of spongy bone metabolism in these children, who should be supplemented with vitamin D in an adjustable dose, possibly higher than 800 IU/24 h to prevent osteopenia.

Vitamin D level in nephrotic syndrome, Factors of impact?

“…Children with NS often display a number of calcium homeostasis disturbances causing abnormal bone histology, including hypocalcemia, reduced serum vitamin D metabolites, impaired intestinal absorption of calcium, and elevated levels of immunoreactive parathyroid hormone (PTH). There is also loss of a variety of plasma proteins and minerals in the urine as well as steroid therapy [4]. Vitamin D (which includes both D2 and D3) is not really a vitamin.…”

Evaluation of Biochemical Bone Markers in Children with Nephrotic Syndrome with Correlation to Its Severity

“…Glucocorticosteroids cause hypocalcemia by reducing intestinal calcium absorption and increased urinary calcium losses Ribeiro et al (12) . However, some studies have reported normal serum calcium levels in children with NS due to increased PTH (13) .…”

Bone Densitometry in Children with Idiopathic Nephrotic Syndrome

“…Furthermore Pańczyk-Tomaszewska. , [21] who accounted for typical serum calcium levels to kids with NS Furthermore explaine as much outcomes that might be expected should expanded PTH.…”

“…These outcomes were in understanding for the individuals news person Toward Pańczyk-Tomaszewska. [21] who closed that Youngsters with NS dealt with with corticosteroids would during danger from claiming bone impostor misfortune. Also, Aceto.…”