Fluids, meds highlight ACP stone prevention guide

Individuals with a history of kidney stones should increase their fluid intake to achieve at least 2 liters of urine per day to prevent recurrence, and if this fails, treatment with a thiazide diuretic, citrate, or allopurinol is recommended, according to a new clinical practice guideline from the American College of Physicians (ACP).

The new evidence-based guideline is published in Annals of Internal Medicine (2014; 161:659-67).

RELATED: Study: Ultrasound over CT for initial stone Dx

“Increased fluid intake spread throughout the day can decrease stone recurrence by at least half with virtually no side effects,” said David Fleming, MD, MA, president of the ACP. “However, people who already drink the recommended amount of liquids, or when increased fluid intake is contraindicated, should not increase their fluid intake.”

The evidence did not show any difference between tap water compared to a specific brand of mineral water, the ACP said in a news release. Evidence also indicated that a decrease in consumption of soft drinks acidified by phosphoric acid, such as colas, is associated with a reduced risk of stone recurrence. (Fruit-flavored soft drinks are often acidified by citric acid.)

The ACP said evidence showed that thiazide diuretics, citrates, or allopurinol effectively reduced recurrence of calcium stones in patients with at least two past stones. No studies directly compared the drugs to each other.

The guideline authors note that doctors also recommend dietary changes to prevent recurring kidney stones, including reducing dietary oxalate (eg, chocolate, beets, nuts, rhubarb, spinach, strawberries, tea, and wheat bran), reducing dietary animal protein and purines, and maintaining normal dietary calcium.

The recommendations are based on published literature in the English language on this topic from 1948 through March 2014. The ACP is the largest medical specialty organization and second-largest physician group in the United States.

More on Stone Disease

Stone patients at greater risk for CHD, stroke

Rising temperatures linked to increased stone risk

Best of AUA 2014: Stone Disease/Endourology

To get weekly news from the leading news source for urologists, subscribe to the Urology Times eNews.