title: Non-dilated urinary tract obstruction.
abstract: OBJECTIVE
  To describe the occurrence of obstructive uropathy in the absence of dilatation of the urinary tract.
  
  
  METHODS
  Five cases of non-dilated obstructive nephropathy are described. All patients were uraemic on presentation. Obstruction was caused by retroperitoneal malignancy in two patients and uric acid lithiasis in the remaining three. All patients had at least one ultrasound examination. Isotope renography and computed tomography were performed in three and four patients respectively. None of these imaging techniques suggested obstruction in any of the cases. Radionuclide scans were characterised by unusually poor perfusion and parenchymal phase images.
  
  
  RESULTS
  An immediate diuresis and a rapid return of normal renal function occurred after relief of the obstruction in all cases.
  
  
  CONCLUSIONS
  The absence of dilatation in obstructive nephropathy is uncommon but may be responsible for delayed diagnosis and management of a readily treatable cause of acute renal failure.
authors.affiliation: Nephrology Department, St Vincent's Hospital, Fitzroy, VIC.
authors.forename: C A
authors.initials: CA
authors.lastname: Somerville
authors.forename: R
authors.initials: R
authors.lastname: Chmiel
authors.forename: J F
authors.initials: JF
authors.lastname: Niall
authors.forename: B F
authors.initials: BF
authors.lastname: Murphy
mesh_terms: D000368:Aged; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012186:Retroperitoneal Neoplasms / Q000150:complications; D014511:Uremia / Q000209:etiology; D014514:Ureteral Calculi / Q000150:complications / Q000175:diagnosis; D014517:Ureteral Obstruction / Q000150:complications / Q000175:diagnosis* / Q000209:etiology / Q000628:therapy; D014567:Urography / Q000379:methods