A foreign body in the kidney.

Urinary infection is frequently due to or accompanied by the deposit of calculi, and in these circumstances it is notoriously difficult to treat the infection satisfactorily so long as the foreign body remains. Rarely a foreign body introduced into the bladder per urethram is found to be the cause of chronic pyuria. Still more rarely-as in the case here recorded-a foreign body may ulcerate through the wall of some part of the alimentary tract into the kidney, ureter or bladder and give rise to urinary infection.