What are kidney stones?
Kidney stones are hard, crystalline deposits that form in the urinary tract when minerals and salts in the urine become concentrated and clump together. They can cause severe flank or back pain, blood in the urine (hematuria), nausea, and sometimes difficulty passing urine. Prevention mainly involves staying well hydrated, reducing intake of excess salt and certain foods (such as those high in oxalate), and maintaining a balanced diet to lower the risk of stone formation.