Biochemical Effect of Dietary Natural Fruit Juice in the Patients with Hypocitraturic Calcium Urolithiasis

Yoon, Seung Hwan; Moon, Young Tae

Abstract

PURPOSE: Citrate is a well recognized inhibitor of the formation of urinary calcium stones, and hypocitraturia plays an important role in the recurrent calcium urolithiasis. We evaluated the biochemical effects of dietary natural fruit juice in calcium stone formers with hypocitraturia in an attempt to decrease or eliminate the need for pharmacological therapy.
MATERIALS AND METHODS
This prospective study included 26 women and 34 men (mean age 42.5 years) with documented calcium urolithiasis. Among 60 patients, hypocitraturia(<320mg/24-hour urine) was detected in 40. Forty patients with hypocitraturia were divided into each 20 patient groups, one for orange juice and the other for grape juice. Twenty patients without hypocitraturia were also divided into each 10 patient groups for the controls. Each bottle of orange and grape juice measures 180ml in volume, which contains citrate of 1.22gm and 0.65gm, respectively. All 60 patients consumed juices at regular intervals, 4 bottles a day for 14 days. Blood and 24-hour urine sample were obtained for biochemical analysis after 7 and 14 days of juice therapy and compared to the baseline values of pre-juice therapy.
RESULTS
The administration of natural fruit juice, either orange or grape, did not result in any significant change in serum biochemical study in all 60 patients(p>0.05). But, levels of urinary citrate were significantly increased in 29(97%) patients in orange juice group(n=30) and were normalized in 19(95%) patients with hypocitraturia. In grape juice group(n=30), levels of urinary citrate were significantly increased in 28(93%) patients and were normalized in 18(90%) patients with hypocitraturia. But, in hypocitraturic patients taking orange juice, urinary oxalate increased in 12(60%) patients. The natural juice therapy was well tolerated. Some G-I trouble occured(11%) but did not require cessation of therapy. Cirtate supplementation with natural fruit juice increased urinary citrate more than 1.5-2 times, but increased urinary oxalate value in orange juice group with hypocitraturia.
CONCLUSIONS
Natural fruit juices, orange and grape, are well tolerated dietary source of citrate, and may be useful as adjunctive treatment for patients with hypocitraturic calcium urolithiasis.