25-HYDROXY-VITAMIN-D IN NEPHROTIC SYNDROME
1977; Elsevier BV; Volume: 310; Issue: 8029 Linguagem: Inglês
10.1016/s0140-6736(77)90118-0
ISSN1474-547X
AutoresH Schmidt-Gayk, Christa Grawunder, W. Tschöpe, Walter Schmitt, Eberhard Ritz, V. Pietsch, K. Andrássy, Roger Bouillon,
Tópico(s)Vitamin D Research Studies
ResumoSerum-25-hydroxy-vitamin-D (25-OHD) levels were measured in 33 patients with nephrotic syndrome (N.S.) without renal insufficiency (urinary protein excretion>3-5 g/24 h/1·73 m2; glomerular filtration-rate >80 ml/min/1·73 m2). Serum-25-OHD levels were low in patients with N.S. (mean 19 nmol/l, range 4-41 nmol/l), compared with a normal range of 25-200 nmol/l. Serum-concentrations of Gcglobulin—the binding protein for vitamin D and its metabolites (D.B.P.)—were significantly (P<0·001) lower in patients with N.S. (mean 340 mg/l, range 190-480 mg/l) than in non-proteinuric controls (mean 440 mg/l, range 376-510 mg/l, measured by radial immunodiffusion). In contrast to non-proteinuric urine, urine of all N.S. patients contained a large amount of 25-OHD-binding capacity; D.B.P. could be detected in all N.S. urines after concentration. Scatchard analysis of the urine demonstrated the presence of a low-affinity and a high-affinity binding protein (tentatively identified as albumin and D.B.P.).These results suggest an acquired deficiency of circulating 25-OHD in N.S. secondary to urinary loss of protein-bound 25-OHD. The biological relevance of the low 25-OHD levels is unknown. There was no clinical evidence of osteomalacia (X-ray, serum- alkaline-phosphatase); however, slightly elevated serum- parathyroid-hormone (P.T.H.) levels would be compatible with borderline vitamin-D depletion.
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