[Gluteal fistula that developed spontaneously from pyonephrosis].

A case is described in which pyonephrosis of 21 months standing has caused gluteal fistula by spontaneously breaking through the deep dorsal musculature. Though the patient has been hospitalized in the surgical ward and treated as out-patient in the specialized surgery for gluteal abscess, i.e. fistula, pyonephrosis maintaining of the fistula was detected and treated only after 18 months. After nephrectomy the fistula closed spontaneously and the patient was cured when leaving the hospital.