What is Urinary calculi?
Urolithiasis (from Greek oûron, "urine", + lithos, "stone", + -iasis) is the formation of urinary calculi (urinary stones), which are calculi formed or located anywhere in the urinary system. It comprises nephrolithiasis (the formation of kidney stones), ureterolithiasis (the formation of stones in the ureters), and cystolithiasis (the formation of bladder stones).
Urinary stones are typically classified by their location or by their chemical composition (calcium-containing, struvite, uric acid, or other compounds). In humans, calcium oxalate is a major constituent of most urinary stones. About 80% of those with kidney stones are men. Men most commonly experience their first episode between 20-30 years of age, while for women the age at first presentation is somewhat later.