title: Detection of medullary and papillary necrosis at an early stage by multiphasic helical computerized tomography.
abstract: OBJECTIVE
  Multiphasic helical computerized tomography (CT) is advocated to identify early manifestations of papillary and medullary necrosis based on decreased enhancement of circumscribed areas in the medullary pyramid. At this stage the devascularizing process can be reversed if causative conditions such as infections or diabetes mellitus are effectively treated.
  
  
  METHODS
  Multiphasic helical CTs were performed in 31 male and 26 female patients with complaints of microscopic hematuria (41), macroscopic hematuria (2), bacteriuria (39) and pyuria (9). Pre-enhancement, arterial, early corticomedullary, parenchymal and excretory phase helical CTs generated 1.25 to 5 mm. thick slices. Followup examination included multiphasic helical CT at 1 and 3 months, and excretory urography for some patients at 3 months.
  
  
  RESULTS
  Bacteriuria was identified as the probable cause of medullary and papillary necrosis in 39 patients, of whom 28 were treated with effective antibiotic therapy, resulting in normalization and re-perfusion of the initial lesion in 16, no change in 5 and progressive disease in 7 at 3-month followup. Of 8 lesions not treated with specific antibiotic therapy 4 progressed and 4 remained unchanged.
  
  
  CONCLUSIONS
  Multiphasic helical CT unlike the excretory urogram can identify medullary and papillary necrosis at an early stage when effective treatment of the underlying cause can reverse the process of devascularization and prevent sloughing of medullary tissues.
authors.affiliation: Department of Radiology and Urology, Tulane University Health Sciences Center, New Orleans, LA, USA.
authors.forename: E K
authors.initials: EK
authors.lastname: Lang
authors.forename: R J
authors.initials: RJ
authors.lastname: Macchia
authors.forename: R
authors.initials: R
authors.lastname: Thomas
authors.forename: R
authors.initials: R
authors.lastname: Davis
authors.forename: G
authors.initials: G
authors.lastname: Ruiz-Deya
authors.forename: R A
authors.initials: RA
authors.lastname: Watson
authors.forename: F
authors.initials: F
authors.lastname: Richter
authors.forename: B
authors.initials: B
authors.lastname: Gayle
mesh_terms: D000328:Adult; D001437:Bacteriuria / Q000150:complications*; D005260:Female; D006417:Hematuria / Q000209:etiology; D006801:Humans; D007668:Kidney / Q000098:blood supply / Q000000981:diagnostic imaging* / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D009336:Necrosis; D011856:Radiographic Image Enhancement; D036542:Tomography, Spiral Computed