A kidney stone, also known as a renal calculus is a solid concretion or crystal aggregation formed in the kidneys from dietary minerals in the urine. Urinary stones are typically classified by their location in the kidney (nephrolithiasis), ureter (ureterolithiasis), or bladder (cystolithiasis), or by their chemical composition (calcium-containing, struvite, uric acid, or other compounds). About 80% of those with kidney stones are men. Men most commonly experience their first episode between 30 and 40 years of age, while for women the age at first presentation is somewhat later.

Signs and symptoms
Pain in the back, belly, or side
Pain or burning during urination
Urgent need to go
Blood in the urine
Cloudy or smelly urine
Going a small amount at a time
Nausea and Vomiting
Fever and chills