Idiopathic Calcium Nephrolithiasis

Abstract

Calcium nephrolithiasis (CaNL) accounts for more than 70% of all renal stones, and its prevalence has increased in the last decades. Under this definition are included patients passing stones, composed of calcium oxalates and/or calcium phosphates. Current views of the pathogenesis of CaNL are based on the role of metabolic abnormalities which concur to render urines more conducive to crystallization. Therefore, the diagnostic approach is aimed at detecting these abnormalities, and the medical treatment assumes that a decrease in the risk of lithogenesis will result in remission or improvement of recurrences. The workup of the patients with CaNL begins with the analysis of passed stones and X-ray, sonography or other imaging techniques. Eligible patients, that is, both recurrent active stone formers and single-stone formers with individual risk factors, are considered for a metabolic evaluation, by which a number of blood and urine parameters are measured and others calculated. These include estimates of urine state of saturation with calcium and uric acid salts, net gastrointestinal alkali absorption, renal threshold of phosphate and other renal clearances and net acid and total nitrogen excretions. Basically, this screening is informative on renal function, metabolic abnormalities and their pathophysiology, risk of stone formation and dietary habits. During treatment it gives information about patient compliance and adverse effects of therapy. The cost of a comprehensive screening in Piedmont is 192,000 ITL (100 Euro) and rises to 300,000 ITL (154 Euro) if hormones and hydroxyproline are measured. In individual patients second- and third-level studies are performed, in order to detect systemic diseases which account for about 20% of CaNL in our series. Cost-to-benefit analysis has shown that the medical procedures for CaNL yield considerable saving in terms of difference between expenditure for drugs and testing and reduction of stone events. However, the current workup cannot be considered exhaustive, because misleading events may hamper the relation between laboratory findings and clinical outcome, and factors other than urine composition have appeared on the scenario of nephrolithiasis. These represent our challenge for the third millennium.

The relationship between insulin, insulin resistance, parathyroid hormone, cortisol, testosterone, and thyroid function tests in the presence of nephrolithiasis: a comprehensive analysis

“…However, previously it was reported that glucocorticoids may increase the risk of kidney stones [10]. Glucocorticoid–dependent nephrolithiasis (GDNL) may result as a consequence of hypercalciuria, hyperuricosuria, and hypercystinuria, which are common features of patients with Cushing's syndrome [20–22] and are clearly associated with kidney stones formation [23]. However, GDNL probably has a multifactorial pathogenesis, because several other factors related with glucocorticoid excess such as obesity, hypertension, insulin resistance may contribute to kidney stones formation [10].…”

Bone and Metabolic Markers in Women With Recurrent Calcium Stones

“…Thus, this population must be closely followed and, even after this first episode, be evaluated with a complete metabolic study because the rule is recurrence [8,9]. Some authors defend that metabolic study and analysis of stone are important for determining different profiles of lithogenic risk, which allows for adequate treatment to be based on risk [10].…”

New step-by-step algorithms for diagnosis of calcium oxalate urolithiasis based on a qualitative mineralogical composition of calculi

“…A systematic review of the experimental and clinical studies on calcium oxalate urolithiasis performed during the last two decades [1,[4][5][6][7][8][12][13][14][15][16][17] has been used to elaborate new step-by-step approaches for diagnosing and treating this frequent disorder. These clinic and laboratory research have included the quantitative mineralogical analysis of calculi by X-ray diffraction or IR-spectroscopy, electronic microscopy study of their texture and biochemical analysis of blood and urine of patients with COH renal stones.…”

“…There are many excellent studies on calcium oxalate urolithiasis that have been performed for the last twenty years (see, for example [4][5][6][7][8][12][13][14][15][16][17] and references therein). These results can provide at least, as a first approximation, the relationship between metabolic disorders that caused COH stone formation and the stone composition.…”