RESUMEN
The aim of the case report is presentation of unusual and heavy clinical course of pyelonephritis with renal tissue necrosis in a child with urinary tract malformation. Nine month old girl was admitted to hospital in heavy clinical status due to pyelonephritis--urosepsis. It was complicated by acute renal insufficiency. Patient was treated by broad-spectrum antibiotics and parenteral nutrition. She was feverish for 14 days. Computed tomography done in order to exclude abdominal abscess showed massive renal tissue necrosis of on both sides. Antibiotic treatment was successful after 6 weeks. Urological evaluation revealed bilateral vesico-ureteral refluxes grade IV. Scintigraphy showed multiple scars. Patient was treated Deflux injections (twice). We noted 5 urinary tract recurrences despite antibiotic profilaxis. GFR of 75 ml/min/1.73 m2 was estimated at age of 16 m. Immunodeficiency or malignancy as background of clinical course were excluded. The case we describe presents severe clinical course of pyelonephritis due to complex urinary tract malformation that is to be considered despite based on modern publications "sparing" strategies of diagnosis and profilaxis in urinary tract malformations.