Grapefruit-sized kidney stone successfully removed.

Sri Lankan Army doctors have removed the world's largest kidney stone, weighing 801 grams and measuring 13.372 centimeters in length, breaking two Guinness World Records. Kidney stones are solid pieces of material that crystallize in the kidney, ureters or bladder due to genetic and environmental factors. They are relatively common and can be prevented by staying hydrated and reducing sodium intake. Stones above 3 millimeters in diameter often require more extensive treatment such as surgery to remove them.