Long-term treatment of renal lithiasis with potassium citrate.

OBJECTIVE

To evaluate the urine metabolic changes induced by sustained potassium citrate (KCit) treatment in patients with either hypocitraturia (HCit) or "unduly acidic urine pH" (UAUpH), and to determine the remission rate in those patients treated for more than 24 months.

METHODS

We retrospectively reviewed the charts of 215 adult patients with recurrent renal stones whose only urinary metabolic risk factors were either HCit (n = 95) or UAUpH (n = 120) and had been treated with KCit for more than 3 months.

RESULTS

In patients with Hcit (55 men and 40 women, mean age was 43 ± 14 years), Kcit therapy (average dose 48 ± 14.7 mEq/d) caused a sustained increase in urinary citrate to normal levels, in urinary potassium and pH and in serum potassium. In patients with UAUpH (73 men and 47 women; mean age 48.7 ± 12 years), Kcit therapy (average dose 42.8 ± 15.5 mEq/d) produced a significant increase in urinary pH, potassium, and uric acid. Remission rate was studied in 35 of these patients, whose median follow-up of 31.6 ± 14.3 months. All of these patients received a mean dose of potassium citrate of 45.4 ± 15.2 mEq/d. In 91% of these patients, there was no stone recurrence, similar for Hcit and UAUpH patients.

CONCLUSIONS

Treatment with potassium citrate corrects the metabolic abnormalities seen in patients with Hcit and UAUpH. This was associated with a very high remission rate of stone disease.