title: How complicated is complicated diverticulitis?--phlegmonous diverticulitis revisited.
abstract: OBJECTIVE
  The purpose of this study is to elucidate the accuracy of a clinical classification system for acute diverticulitis with special regard to "phlegmonous diverticulitis".
  
  
  METHODS
  A consecutive patient series (n = 318; General Hospital Nuremberg, 1/2004-12/2006) was classified preoperatively (imaging with 4/16-slice spiral CT scanner) according to the Hansen and Stock (H&S) classification which is commonly used in Germany and evaluated based on histopathology.
  
  
  RESULTS
  Pre-treatment classification grouped 30 patients (9.4%) as uncomplicated diverticulitis (type I according to H&S), for whom treatment was merely conservative. One hundred twelve patients (35.2%) were classified as phlegmonous diverticulitis (type IIA), 84 (26.4%) as "covered perforations" (type IIB) and 27 (8.5%) as "free perforations" (type IIC), and 54 (17.0%) as chronically recurrent diverticulitis (type III, 17.0%). The remaining 11 patients (3.5%) were not staged preoperatively. Accuracy of staging of complicated diverticulitis differed significantly between type IIC (100.0%), type IIB (91.0%), and type IIA (36.1%). The latter group was frequently understaged as it concealed a substantial number of patients (n = 44; 53.0%) with IIB disease. Neither laboratory tests (CRP/WBC) nor clinical parameters allowed distinction of correctly and falsely staged patients with type IIA disease.
  
  
  CONCLUSIONS
  Patients with phlegmonous diverticulitis (type IIA) represent the most challenging group among patients with acute diverticulitis as they are frequently understaged and conceal cases with covered perforations (type IIB). This may support the view to subsume phlegmonous diverticulitis (type IIA) under complicated diverticulitis.
authors.affiliation: Department of General-, Visceral-, Vascular and Pediatric Surgery, University Hospital Wuerzburg, Wuerzburg, Germany.
authors.forename: Christian F
authors.initials: CF
authors.lastname: Jurowich
authors.forename: Stefanie
authors.initials: S
authors.lastname: Jellouschek
authors.forename: Ralf
authors.initials: R
authors.lastname: Adamus
authors.forename: Reinhard
authors.initials: R
authors.lastname: Loose
authors.forename: Annette
authors.initials: A
authors.lastname: Kaiser
authors.forename: Christoph
authors.initials: C
authors.lastname: Isbert
authors.forename: Christoph-Thomas
authors.initials: CT
authors.lastname: Germer
authors.forename: Burkhard H A
authors.initials: BH
authors.lastname: von Rahden
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004239:Diverticulitis, Colonic / Q000145:classification* / Q000150:complications* / Q000473:pathology / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011300:Preoperative Care; D012680:Sensitivity and Specificity