Randomized Clinical Study, Comparative of Parallel Groups, to Evaluate the Effectiveness of Three Preparations of Potassium Citrate in Producing an Increase in Urinary pH in Patients with a History of Kidney Stones

Background: A very strict control of urinary pH is recommended to maintain it between 5.5 and 6.2, preventing formation or recurrence of crystals. Kidney stones are a common problem, with a high rate of recurrence, not altered by the success of surgery. Medical treatment prevents recurrence. Potassium Citrate inhibits crystallization of calcium salts. It influences calculogenesis by increasing urinary citrates and alkalinizing the urine. Purpose: to evaluate the similarity in the effect of three K citrate products, K citrate reference product Urocit® 10 mEq, and K citrate from Laboratorios LETI S.A.V., 10 mEq and 15 mEq, on urinary pH. Materials and Methods: We carried out a prospective, randomized study of three parallel groups. We admitted female and male patients with history of kidney stones or evidence of lithiasis (grit, microlithiasis) in the renal echosonogram. Laboratory assessments: urine, 24-hour urine, urinary pH, Calcium, uric acid, Phosphorus, Sodium, protein and urinary creatinine at times: start, day 7, day 21, 30 of treatment. Results: all three products produced a slight increase in urinary pH in the simple urine test and 24-hour urine, with no differences between groups or their logarithmically transformed means and their CI95, which did not exceed the range between 80% and 125%. Conclusions: K Citrate, 10 mEq and 7.5 mEq, from Laboratorios LETI, S.A.V., at a dose of 30 mEq daily in patients with history of kidney stones are equivalent to the reference product Urocit®, in its effects on urinary pH in 24-hour urine, and in the simple urine test.