Affect adults over age 30, occur more often in men. Causes No known underlying cause, in most cases. Blockage at any level. The pain usually appears first in the back, just below the ribs. Over several hours or days, the pain follows the stone's course through the ureter toward the groin.
Pain stops when the stone passes.
Traces of blood in urine. Urine may appear cloudy or dark. Risk Factors Decreased urine volume due to dehydration or hot, dry weather. Family history of kidney stones. Excess alcohol consumption.