Impact of long-term potassium citrate therapy on urinary profiles and recurrent stone formation.
OBJECTIVE
Potassium citrate therapy has become one of the cornerstones of medical stone management. We elucidated the long-term effects of potassium citrate on urinary metabolic profiles and its impact on stone formation rates.


METHODS
We performed a retrospective cohort study in patients treated at the Comprehensive Kidney Stone Center at our institution between 2000 and 2006. Patients with pre-therapy and post-therapy 24-hour urinary profiles available who remained on potassium citrate for at least 6 months were included in the analysis.


RESULTS
Of the 1,480 patients with 24-hour urinary profiles 503 met study inclusion criteria. Mean therapy duration was 41 months (range 6 to 168). Overall a significant and durable change in urinary metabolic profiles was noted as soon as 6 months after the onset of therapy. These changes included increased urinary pH (5.90 to 6.46, p <0.0001) and increased urinary citrate (470 to 700 mg a day, p <0.0001). The stone formation rate also significantly decreased after the initiation of potassium citrate from 1.89 to 0.46 stones per year (p <0.0001). There was a 68% remission rate and a 93% decrease in the stone formation rate.


CONCLUSIONS
Potassium citrate provides a significant alkali and citraturic response during short-term and long-term therapy with the change in urinary metabolic profiles sustained as long as 14 years of treatment. Moreover, long-term potassium citrate significantly decreases the stone formation rate, confirming its usefulness in patients with recurrent nephrolithiasis.
Robinson
Marnie R
MR
Comprehensive Kidney Stone Center, Division of Urologic Surgery, Duke University Medical Center, Durham, North Carolina, USA.
Leitao
Victor A
VA
Haleblian
George E
GE
Scales
Charles D
CD
Chandrashekar
Aravind
A
Pierre
Sean A
SA
Preminger
Glenn M
GM
D015331:Cohort Studies; D004232:Diuretics / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000188:drug therapy* / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D019357:Potassium Citrate / Q000627:therapeutic use*; D012008:Recurrence; D012189:Retrospective Studies; D013997:Time Factors
D004232:Diuretics; D019357:Potassium Citrate