Urinary lithiasis and idiopathic hypercalciuria: the importance of dietary intake evaluation

Abstract

Purpose: To evaluate food intake of patients with urinary lithiasis and idiopathic hypercalciuria (IH). Materials and Methods:Between August 2007 and June 2008, 105 patients with lithiasis were distributed into 2 groups: Group 1 (n = 55) -patients with IH (urinary calcium excretion > 250 mg in women and 300 mg in men with normal serum calcium); Group 2 (n = 50) -normocalciuria (NC) patients . Inclusion criteria were: age over 18, normal renal function (creatinine clearance ≥ 60 mL/min), absent proteinuria and negative urinary culture. Pregnant women, patients with some intestinal pathology, chronic diarrhea or using corticoids were excluded. The protocol of metabolic investigation was based on non-consecutive collection of two 24-hour samples for dosages of: calcium, sodium, uric acid, citrate, oxalate, magnesium and urinary volume. Food intake was evaluated through the quantitative method of Dietary Register of three days. Results: Urinary excretion of calcium (433.33 ± 141.92 vs. 188.93 ± 53.09), sodium (280.08 ± 100.94 vs. 200.44.93 ± 65.81), uric acid (880.63 ± 281.50 vs. 646.74 ± 182.76) and magnesium (88.78 ± 37.53 vs. 64.34 ± 31.84) was significantly higher in the IH group in comparison to the NC group (p < 0.05). As regards the nutritional composition of food intake of IH and NC groups, there was no statistical significant difference in any nutrient evaluated. Conclusion: In our study, no difference was observed in the food intake of patients with urinary lithiasis and IH or NC.

Metabolic investigation in patients with nephrolithiasis

“…For example, an elevated intake of sodium has a high impact on the development of hypercalciuria. ( 8 – 10 )…”

Biochemical Alterations in Patients with Oxalocalcic Lithiasis, the Influence of Sex, Age, and Body Mass Index

“…In this study, 10.7% of the patients presented an elevation of urinary sodium. The association of urinary sodium with urinary volume, pH, Oxalate, and citrate has also been described in the literature (9,26,27).…”

Influence of clinical therapy and nutritional counseling on the recurrence of urolithiasis

“…All patients were also instructed to maintain a protein intake of 0.8 to 1 g/kg body weight/ day and an adequate calcium intake (800 to 1000 mg/ day) 8 . Salt restriction (less than 5 g/ day) was recommended if appropriate based on their 24h urine sodium excretion 9 .…”

“…Both dietary changes and specific drug treatments are important in urolith recurrence 6,7 . Certain nutrients may promote or inhibit urolith formation 8,9 . Drinking more liquids influences lithogenesis by increasing urinary volume and decreasing the concentration of lithogenic components 10 .…”