A 42-year-old man kept developing painful stones in his right kidney. He already had a known reason to form them: cystinuria, a rare inherited condition that produces cystine stones. But when surgeons went in with a scope to clear the latest stone, they found something else holding it together.
A metallic, wire-like object was poking into the kidney's urine-collecting chamber, its surface crusted with stone. It was an embolization coil, a tiny device placed three years earlier to stop serious bleeding after a previous kidney stone operation.
