An association between kidney stone composition and urinary metabolic disturbances in children.

Objective: To determine kidney stone composition in children and to correlate stone fractions with urinary pH and metabolic urinary risk factors.

Patients And Methods: We studied 135 pediatric patients with upper urinary tract lithiasis in whom excreted or extracted stones were available for analyses. Composition of stones was analyzed.

Correspondence between Ca²⁺ and calciuria, citrate level and pH of urine in pediatric urolithiasis.

Background: Hypercalciuria and hypocitraturia are considered the most important risk factors for urolithiasis. Citrate binds to urinary calcium to form a soluble complex which decreases the availability of ionized calcium (Ca(2+)) necessary for calcium oxalate formation and phosphate crystallization. The aims of this study were to assess the Ca(2+) fraction in relation to total calciuria, citraturia and urinary pH and to determine whether urinary Ca(2+) concentration is a helpful biomarker in metabolic evaluation of children with urolithiasis.