title: Peritoneal dialysis peritonitis by anaerobic pathogens: a retrospective case series.
abstract: BACKGROUND
  Bacterial infections account for most peritoneal dialysis (PD)-associated peritonitis episodes. However, anaerobic PD peritonitis is extremely rare and intuitively associated with intra-abdominal lesions. In this study, we examined the clinical characteristics of PD patients who developed anaerobic peritonitis.
  
  
  METHODS
  We retrospectively identified all anaerobic PD peritonitis episodes from a prospectively collected PD registry at a single center between 1990 and 2010. Only patients receiving more than 3 months of PD were enrolled. We analyzed clinical features as well as outcomes of anaerobic PD peritonitis patients.
  
  
  RESULTS
  Among 6 patients, 10 episodes of PD-associated peritonitis were caused by anaerobic pathogens (1.59% of all peritonitis episodes during study the period), in which the cultures from 5 episodes had mixed growth. Bacteroides fragilis was the most common species identified (4 isolates). Only 3 episodes were associated with gastrointestinal lesions, and 4 episodes were related to a break in sterility during exchange procedures. All anaerobic pathogens were susceptible to clindamycin and metronidazole, but penicillin resistance was noted in 4 isolates. Ampicillin/sulbactam resistance was found in 2 isolates. In 5 episodes, a primary response was achieved using the first-generation cephalosporin and ceftazidime or aminoglycoside. In 3 episodes, the first-generation cephalosporin was replaced with aminoglycosides. Tenckhoff catheter removal was necessary in 2 episodes. Only one episode ended with mortality (due to a perforated bowel).
  
  
  CONCLUSIONS
  Anaerobic PD-associated peritonitis might be predominantly caused by contamination, rather than intra-abdominal events. Half of anaerobic PD-associated peritonitis episodes had polymicrobial growth. The overall outcome of anaerobic peritonitis is fair, with a high catheter survival rate.
authors.forename: Chia-Ter
authors.initials: CT
authors.lastname: Chao
authors.forename: Szu-Ying
authors.initials: SY
authors.lastname: Lee
authors.forename: Wei-Shun
authors.initials: WS
authors.lastname: Yang
authors.forename: Huei-Wen
authors.initials: HW
authors.lastname: Chen
authors.forename: Cheng-Chung
authors.initials: CC
authors.lastname: Fang
authors.forename: Chung-Jen
authors.initials: CJ
authors.lastname: Yen
authors.forename: Chih-Kang
authors.initials: CK
authors.lastname: Chiang
authors.forename: Kuan-Yu
authors.initials: KY
authors.lastname: Hung
authors.forename: Jenq-Wen
authors.initials: JW
authors.lastname: Huang
mesh_terms: D000328:Adult; D000368:Aged; D001421:Bacteria, Anaerobic; D001424:Bacterial Infections / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D015331:Cohort Studies; D004866:Equipment Contamination / Q000517:prevention & control; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010530:Peritoneal Dialysis / Q000009:adverse effects*; D010538:Peritonitis / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology*; D011446:Prospective Studies; D012189:Retrospective Studies; D055815:Young Adult