Ascorbic acid is an abettor in calcium urolithiasis: an experimental study.

Two sets of animal experiments using guinea pigs were planned to evaluate the effect of ascorbic acid supplementation on the lithogenic process. In the first set of experiments, 10, 40, and 60 mg doses of ascorbic acid/100g body weight/day were given for 105 days. Neither of the ascorbic acid doses given induced crystalluria, calcification or stone formation, thereby confirming our previous findings that ascorbic acid in the doses used by clinicians does not cause urolith formation. In the second set of experiments, ascorbic acid was supplemented in hypercalciuric (induced by calcium carbonate feeding) and hyperoxaluric (induced by sodium oxalate feeding) animals for 45 days. The results indicated that it exacerbated the calcification process in renal and bladder tissue.

Effectiveness of a unani therapy (sangesarmahi) in management of urinary stone disease.

A Unani medicine called fish stones, an isolate from the skull of Channa sp. when given to stone bearing patient daily in 3 equally divided doses (25 mg/capsule) for 5 days, spontaneously voided the stone in 36% of the stone patients during 5 days of therapy. The therapy did not influence the urinary chemistry and was not a powerful expulsion agent of stone but did effect on ureteric muscles to facilitate the movement of stone down the urinary tract. In guinea pigs, the therapy could not reduce the intensity of experimentally induced hyperoxaluria but showed several other beneficial effects. It decreased urinary uric acid and mucoprotein levels, serum LDH and ALT level; prevented rise in liver LDH and GAO activities and kidney-LDH activity. Histological examination revealed decreased intensity of calcification in liver, kidney and bladder tissues.

Effect of dietary methionine and inorganic sulfate with and without calcium supplementation, on urinary calcium excretion of guinea pigs (Cavia porcellus).

Supplementation of sodium sulfate and DL-methionine along with the standard diet to guinea pigs nearly doubled the urinary calcium in 6 weeks. This was probably due to decreased tubular reabsorption of calcium which was complexed with sulfate in the tubular lumen. A mild calcium load didn't further enhance calcium excretion in sodium sulfate supplemented group, but did so in methionine supplemented group. It may be due to methionine which might have increased the intestinal absorption of calcium. Both of these compounds increased citric acid excretion and decreased magnesium excretion.

Effect of dietary salt (NaCl) supplementation on urinary profile of guinea pigs (Cavia porcellus).

Sodium chloride supplementation (120 mg/kg of body weight/day) for 12 days increased the urinary excretion of calcium from 91.6 +/- 9.0 to 159.4 +/- 16.0 mumol/day and of sulphate from 266.8 +/- 24.5 to 1176.9 +/- 87.2 mumol/day in guinea pigs. The stone risk due to increased urinary calcium excretion could possibly be counterbalanced by increasing urinary sulphate excretion. High salt intake, thus, could not increase the risk of stone formation.

Interdependence of urinary factors in calcareous bladder stone patients.

Twenty-four-hour urinary excretion of calcium, oxalic acid, inorganic phosphorus, magnesium and citric acid was examined in fifty-nine stone formers with bladder stones. Hypercalciuria and hyperoxaluria were present in 18.6% and 44.1%, respectively, while 11.9% of patients had both abnormalities. Hypomagnesuria and hypocitraturia were present in 67.8% and 69.5%, respectively, while 45.7% had both of these abnormalities. Normal urine chemistry in respect of parameters studied was observed only in 1.7% of cases. In 15.2% one risk factor was present, while 83.1% had two or more risk factors. "Path" analysis of the urinary parameters directly related to calcium lithiasis showed that magnesium and oxalic acid have substantial influence on calcium excretion, whereas citric acid had none. The influence of phosphorus did not provide any consistent trend.

Urinary biochemical profile of patients with ureteric calculi in Jodhpur region (north western India).

Urine chemistry of 42 normal subjects (NS) and 59 ureteric stone formers (SF) from Jodhpur region of Rajasthan, India is presented. Twenty four hour urinary levels of calcium, oxalic acid and uromucoids were significantly higher and levels of magnesium, citric acid and inorganic phosphorus were significantly lower in SF as compared to NS. No significant difference was observed in the uric acid, sodium and potassium levels in the two groups. Significant correlation was observed between calcium and magnesium; calcium and oxalic acid; calcium and citric acid; magnesium and oxalic acid; and oxalic acid and citric acid in NS on the basis of mmol/l but not on the basis of mmol/24 h. Calcium and oxalic acid correlation was uninfluenced by magnesium and citric acid levels. The log of risk factor index (RI) was higher (p less than 0.001) in SF (-1.652) as compared to NS (-2.103). The log of ion activity product (IAP) was also higher (p less than 0.001) in SF (-3.192 X 10(-3)) than in NS (-2.914 X 10(-1)). Based on RI and IAP, a scale has been devised for the prediction of the risk of stone formation and recurrence.