MARKERS OF BONE TURNOVER IN PATIENTS WITH NEPHROLITHIASIS

Nineteen patients with active nephrolithiasis, 14 patients with nonact ive nephrolithiasis, and 17 healthy subjects were examined under stand ardized intake of calcium, phosphorus, purine, and protein. In patient s both with active and nonactive renal stone disease the following abn ormalities were found: elevated plasma levels of PTH and osteocalcin, increased activity of the bone isozyme of alkaline phosphatase, low pl asma levels of phosphate, and increased urinary excretion of calcium a nd oxalic acid. These abnormalities were more marked in patients with active than with nonactive nephrolithiasis. No correlation was found b etween plasma PTH levels and parameters of bone turnover as well as ca lciuria and oxaluria. Results presented in this paper suggest that Smi th's criteria of active renal stone disease are of minor pathogenetic and therapeutic value, and patients with active nephrolithiasis differ from nonactive renal stone formers by more elevated oxaluria and mark ers of bone turnover and more marked abnormalities in calcium-phosphat e metabolism related parameters.