Rarely the underlying cause is primary oxaluria, a liver enzyme deficiency leading to massive cortical and medullary nephrocalcinosis, and renal failure.Ĭertain medications 14 can predispose to calcium oxalate or calcium phosphate calculi, including: Interestingly hyperuricosuria is also associated with increased calcium-containing stone formation and is thought to be related to the uric acid crystals acting as a nidus on which calcium oxalate and calcium phosphate can precipitate 6. In most instances, no specific cause can be identified, although most patients have idiopathic hypercalciuria without hypercalcemia.īrushite is a unique form of calcium phosphate stones that tends to recur quickly if patients are not treated aggressively with stone prevention measures and are resistant to treatment with shock wave lithotripsy. Most renal calculi contain calcium, usually in the form of calcium oxalate (CaC 2O 4) and often mixed with calcium phosphate (CaPO 4) 1,6. Crohn disease) resulting in fats binding calcium Low gut absorption of calcium, leading to increased absorption of oxalate Hypercalciuria: most common metabolic abnormality Urease hydrolyzes urea to ammonium thus increasing urinary pH The more common composition of stones include (more detail below):Ĭalcium oxalate +/- calcium phosphate: ~75%Ĭertain risk factors have been identified including 8:Įspecially with urease producing bacteria (see below) The composition of urinary tract stones varies widely depending upon metabolic alterations, geography, and presence of infection, and their size varies from gravel to staghorn calculi. In children, vague abdominal pain is more typical than the classic colicky pain described by adults 26. Some patients may also present with the complication of obstructive pyelonephritis, and may, therefore, have a septic clinical presentation. Hematuria, although common, may be absent in approximately 15% of patients 1. Small stones that arise in the kidney are more likely to pass into the ureter where they may result in renal colic. Although some renal stones remain asymptomatic, most will result in pain.

Non obstructive left renal calculus