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M A Nassuato

Publications and source records attributed to M A Nassuato.

4 recordsLinked to original sources

Plasma phospholipid arachidonic acid content and calcium metabolism in idiopathic calcium nephrolithiasis.

BACKGROUND: Reports of an increase in plasma and erythrocyte phospholipid arachidonic acid content and in urinary prostaglandin E2 (PGE2) excretion in patients with idiopathic calcium nephrolithiasis suggested their crucial role in the pathogenesis of hypercalciuria, a well-known risk factor for lithogenesis. METHODS: To confirm this hypothesis, 15 healthy subjects and 20 nephrolithiasis patients were evaluated for plasma phospholipid polyunsaturated fatty acid content and PGE2 concentration, serum parathyroid hormone, 25 hydroxyvitamin D3, 1, 25-dihydroxyvitamin D3, and bone-specific alkaline phosphatase levels, as well as urinary excretion of calcium, biochemical markers of bone resorption (hydroxyproline and crossLaps), and intestinal calcium absorption. Furthermore, the effect of a 30-day fish-oil diet supplementation on the previously mentioned parameters was investigated in the patients. RESULTS: At baseline, patients compared with controls showed higher levels of plasma phospholipid arachidonic acid content (P = 0.002), PGE2 (P = 0.0004), serum 25-vitamin D3 (P = 0.001), and 1,25-vitamin D3 (P = 0.001), urinary excretion of calcium (P = 0.001), hydroxyproline (P = 0.007), and crossLaps (P = 0.019), as well as intestinal calcium absorption (P = 0.03 at 60 min). Fish oil supplementation induced a reduction in the plasma phospholipid arachidonic acid level (P < 0.0001), and except for serum concentrations of 25-vitamin D3, normalized baseline blood and urinary parameters, including intestinal calcium absorption. A close correlation between plasma PGE2 and serum 1,25-vitamin D3 (P = 0.004) and between phospholipid arachidonic acid and intestinal calcium absorption (P = 0.0002) and calciuria (P = 0.007) was observed, as well as between urine excretion of crossLaps and hydroxyproline (P < 0.0001), crossLaps and calcium (P < 0.0001), and hydroxyproline and calcium (P < 0.0001). CONCLUSIONS: These findings indicate that the phospholipid arachidonic acid content anomaly could represent the primary event responsible for the mosaic of metabolic and clinical alterations that are distinctive features of renal stone formers, and suggest that a common pathogenetic mechanism might account for the several forms of hypercalciuria detected in idiopathic calcium nephrolithiasis.

Adult↗

The abnormal red-cell oxalate transport is a risk factor for idiopathic calcium nephrolithiasis: a prospective study.

An abnormal erythrocyte transmembrane oxalate flux was described in recurrent idiopathic calcium nephrolithiasis. To verify whether it might represent a risk marker of renal stone disease, two prospective studies were carried out. One hundred ninety patients with idiopathic calcium nephrolithiasis who were enrolled at their first episode of lithiasis during the period 1984 to 1986, form the basis of the first prospective study. The impact of erythrocyte oxalate transport anomaly, gender, familial occurrence of nephrolithiasis, hypercalciuria, hyperoxaluria, and hyperuricosuria on stone recurrence by both bivariate and multivariate analysis of frequencies was assessed. The predictive value of the erythrocyte anomaly for a patient's becoming a stone former was also assessed in five nephrolithiasis families. Recurrence occurred in 57.9% of patients; this was significantly associated with the erythrocyte anomaly, hyperoxaluria, and male gender. However, when using multivariate analysis, only gender and the erythrocyte anomaly were statistically significant and were independent predictors of recurrency. The probability of stone recurrency predicted by the logistic model ranged from 30.1% for women with normal erythrocyte oxalate transport, to 73.4% for men with the erythrocyte anomaly. The family follow-up showed that only subjects with the erythrocyte abnormality become renal stone-formers in the 8-yr survey. By showing the predictive value of the erythrocyte oxalate anomaly for recurrent calcium nephrolithiasis, our findings support the notion that this anomaly is a risk factor in renal stone disease.

Adolescent↗