A kidney stone does not usually cause symptoms when it remains in the kidney. However, when a stone moves from the kidney into the ureter, it can cause a blockage of flow of urine, increasing pressure and swelling within the kidney and leading to the symptoms of kidney stones.

Severe, often excruciating, pain is the hallmark symptom of kidney stones. The pain is located in the flank or low back and can radiate to the front of the abdomen. It can cause scrotal or testicular pain in males. The pain is referred to as renal colic and typically occurs in intermittent waves. Associated symptoms can include sweating, nausea, and vomiting. Sometimes, blood can be seen in the urine. If an associated urinary tract infection is present, symptoms like difficulty urinating, painful urination, and urinary urgency can develop.

Causes of kidney stones

The cause of kidneys stones can vary depending on the type of stone that forms. Dehydration from reduced fluid intake or strenuous exercise without adequate fluid replacement increases the risk of kidney stones. Obstruction to urine outflow can also lead to stone formation. Uric acid kidney stones can occur due to elevated uric acid levels in their blood (hyperuricemia). Certain urinary tract infections can increase the risk of kidney stone formation. These are known as struvite or infection stones. Other metabolic conditions (such as gout) and certain medications can also increase the risk.