Evidence against a contribution of conventional urine risk factors to de novo ESRD renal stones.

BACKGROUND The authors measured urine and blood stone risk factors in African-American (AA) haemodialysis (HD) patients with new onset of stones during dialysis. METHODS Patients with nephrolithiasis (NL) newly manifested during dialysis were matched by age, sex and urine output and dialysis duration to AA HD patients without history or symptoms of stones. Two 24 h urine and serum samples were collected and analysed for conventional stone risk factors. RESULTS Three percent of the patients formed new stones while on HD; none had formed stones prior to end-stage renal disease. Newly onset NL patients had higher urine citrate and lower serum potassium levels than HD patients without stones. CONCLUSION Usual stone risk factors did not correlate with new stones during dialysis.