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, ureter, or bladder, or by their chemical composition. About 80% of those with kidney stones are men. Kidney stones typically leave the body by passage in the urine stream, and many stones are formed and passed without causing symptoms. If stones grow to sufficient size they can cause obstruction of the ureter. Ureteral obstruction causes postrenal azotemia and hydronephrosis, as well as spasm of the ureter. This leads to pain, most commonly felt in the flank, lower abdomen, and groin. Renal colic can be associated with nausea, vomiting, fever, blood in the urine, pus in the urine, and painful urination. Renal colic typically comes in waves lasting 20 to 60 minutes, beginning in the flank or lower back and often radiating to the groin or genitals. The diagnosis of kidney stones is made on the basis of information obtained from the history, physical examination, urinalysis, and radiographic studies. Ultrasound examination and blood tests may also aid in the diagnosis. Wikipedia [ - ]

A kidney stone, also known as a renal calculus is a solid concretion or crystal aggregation... [ + ]