Defining hypercalciuria in nephrolithiasis.

The classic definition of hypercalciuria, an upper normal limit of 200  mg/day, is based on a constant diet restricted in calcium, sodium, and animal protein; however, random diet data challenge this. Here our retrospective study determined the validity of the classic definition of hypercalciuria by comparing data from 39 publications analyzing urinary calcium excretion on a constant restricted diet and testing whether hypercalciuria could be defined when extraneous dietary influences were controlled. These papers encompassed 300 non-stone-forming patients, 208 patients with absorptive hypercalciuria type I (presumed due to high intestinal calcium absorption), and 234 stone formers without absorptive hypercalciuria; all evaluated on a constant restricted diet.

Effect of gonadotropin-releasing hormone agonist and medroxyprogesterone acetate on calcium metabolism: a prospective, randomized, double-blind, placebo-controlled, crossover trial.

Objective: The purpose of this study was to prospectively compare the effectiveness of administering medroxyprogesterone acetate (MPA; 20 mg/d) in either the first (protocol A) or last (protocol B) 12-week period as well as a 6-month course of the GnRH agonist (GnRH-a; leuprolide acetate; 1 mg/d, SC) on calcium (Ca) metabolism.

Design: Prospective, randomized, double-blind, placebo-controlled, crossover trial.

Setting: Clinical research center, university hospital.