Hydroxycitrate: a potential new therapy for calcium urolithiasis

Area of Science:

• Nephrology
• Biochemistry
• Urology

Background:

• Alkali supplements increase urine citrate, aiding calcium kidney stone treatment by inhibiting crystallization.
• Alkali's urine pH increase may limit effectiveness for calcium phosphate stones and in patients with alkaline urine.

Purpose of the Study:

• To evaluate hydroxycitrate as a potential therapeutic agent for calcium kidney stones.
• To assess hydroxycitrate's efficacy in inhibiting calcium oxalate crystallization and complexing calcium.
• To review existing human data on hydroxycitrate and identify research gaps.

Main Methods:

• In vitro studies assessing hydroxycitrate's calcium-complexing capacity and crystallization inhibition.
• Review of current human knowledge regarding hydroxycitrate ingestion and urinary excretion.
• Identification of necessary research for clinical recommendation.

Main Results:

• Hydroxycitrate demonstrates in vitro calcium-binding capacity comparable to citrate.
• Hydroxycitrate effectively inhibits and dissolves calcium oxalate monohydrate crystals in vitro.
• Hydroxycitrate is excreted in urine and does not alter urine pH, unlike citrate therapy.

Conclusions:

• Hydroxycitrate presents a potential alternative to alkali citrate for kidney stone therapy.
• Its non-metabolized nature and urine pH-neutral effect are advantageous.
• Further clinical studies are required to establish hydroxycitrate as a recommended kidney stone treatment.