title: [Stage II focal xanthogranulomatous pyelonephritis].
abstract: OBJECTIVE
  To report a case of focalized stage II xanthogranulomatous pyelonephritis and the diagnostic difficulties encountered.
  
  
  METHODS
  A 63-year-old female consulted at the emergency services for fever during the last two months and right lumbar pain. Urinary cultures were negative. A CT scan showed a poorly-defined heterogeneous mass in the lower pole of the right kidney. Fine needle punction-aspiration biopsy was compatible with renal cell carcinoma. The patient underwent radical nephrectomy.
  
  
  RESULTS
  The histopathological study showed focalized stage II xanthogranulomatous pyelonephritis but no evidence of neoplasia.
  
  
  CONCLUSIONS
  Xanthogranulomatous pyelonephritis can mimic the clinical, cytological and imaging features of renal neoplasia.
authors.affiliation: Servicio y Catedra de Urología, Hospital Universitario del Mar, Universidad Autónoma de Barcelona, Barcelona, España. 92863@imas.imim.es
authors.forename: Noelia
authors.initials: N
authors.lastname: Alonso Gracia
authors.forename: Joan
authors.initials: J
authors.lastname: Griño Garreta
authors.forename: Oscar
authors.initials: O
authors.lastname: Bielsa Gali
authors.forename: Antoni
authors.initials: A
authors.lastname: Gelabert-Mas
mesh_terms: D001707:Biopsy, Needle; D002292:Carcinoma, Renal Cell / Q000175:diagnosis*; D003937:Diagnosis, Differential; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D007680:Kidney Neoplasms / Q000175:diagnosis*; D008875:Middle Aged; D011705:Pyelonephritis, Xanthogranulomatous / Q000175:diagnosis* / Q000000981:diagnostic imaging / Q000473:pathology / Q000601:surgery; D014057:Tomography, X-Ray Computed