title: Clinical and microbiological characteristics of perianal infections in adult patients with acute leukemia.
abstract: BACKGROUND
  Perianal infection is a common problem for patients with acute leukemia. However, neutropenia and bleeding tendency are relatively contraindicated to surgical intervention. The epidemiology, microbiology, clinical manifestations and outcomes of perianal infection in leukemic patients are also rarely discussed.
  
  
  METHODS
  The medical records of 1102 adult patients with acute leukemia at a tertiary medical center in Taiwan between 2001 and 2010 were retrospectively reviewed and analyzed.
  
  
  RESULTS
  The prevalence of perianal infection was 6.7% (74 of 1102) in adult patients with acute leukemia. Twenty-three (31%) of the 74 patients had recurrent episodes of perianal infections. Patients with acute myeloid leukemia had higher recurrent rates than acute lymphoblastic leukemia patients (p = 0.028). More than half (n = 61, 53%) of the perianal infections were caused by gram-negative bacilli, followed by gram-positive cocci (n = 36, 31%), anaerobes (n = 18, 15%) and Candida (n = 1, 1%) from pus culture. Eighteen patients experienced bacteremia (n = 24) or candidemia (n = 1). Overall 41 (68%) of 60 patients had polymicrobial infection. Escherichia coli (25%) was the most common micro-organism isolated, followed by Enterococcus species (22%), Klebsiella pneumoniae (13%), and Bacteroides species (11%). Twenty-five (34%) of 74 patients received surgical intervention. Acute leukemia patients with surgically managed anal fistulas tended to have fewer recurrences (p = 0.067). Four (5%) patients died within 30 days after diagnosis of perianal infection. Univariate analysis of 30-day survival revealed the elderly (≧ 65 years) (p = 0.015) and patients with shock (p<0.001) had worse outcome. Multivariate analysis showed septic shock to be the independent predictive factor of 30-day crude mortality of perianal infections (p = 0.016).
  
  
  CONCLUSIONS
  Perianal infections were common and had high recurrence rate in adult patients with acute leukemia. Empirical broad-spectrum antibiotics with anaerobic coverage should be considered. Shock independently predicted 30-day crude mortality. Surgical intervention for perianal infection remains challenging in patients with acute leukemia.
authors.affiliation: Department of Internal Medicine, National Taiwan University Hospital, Taipei, Taiwan.
authors.forename: Chien-Yuan
authors.initials: CY
authors.lastname: Chen
authors.forename: Aristine
authors.initials: A
authors.lastname: Cheng
authors.forename: Shang-Yi
authors.initials: SY
authors.lastname: Huang
authors.forename: Wang-Huei
authors.initials: WH
authors.lastname: Sheng
authors.forename: Jia-Hau
authors.initials: JH
authors.lastname: Liu
authors.forename: Bo-Sheng
authors.initials: BS
authors.lastname: Ko
authors.forename: Ming
authors.initials: M
authors.lastname: Yao
authors.forename: Wen-Chien
authors.initials: WC
authors.lastname: Chou
authors.forename: Hui-Chi
authors.initials: HC
authors.lastname: Lin
authors.forename: Yee-Chun
authors.initials: YC
authors.lastname: Chen
authors.forename: Woei
authors.initials: W
authors.lastname: Tsay
authors.forename: Jih-Luh
authors.initials: JL
authors.lastname: Tang
authors.forename: Shan-Chwen
authors.initials: SC
authors.lastname: Chang
authors.forename: Hwei-Fang
authors.initials: HF
authors.lastname: Tien
mesh_terms: D000038:Abscess / Q000150:complications* / Q000382:microbiology*; D000208:Acute Disease; D000293:Adolescent; D000328:Adult; D000368:Aged; D001424:Bacterial Infections / Q000150:complications*; D005260:Female; D006761:Hospitals; D006801:Humans; D007938:Leukemia / Q000150:complications*; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D009181:Mycoses / Q000150:complications*; D012003:Rectal Fistula / Q000150:complications* / Q000382:microbiology*; D012189:Retrospective Studies; D055815:Young Adult