title: Monomicrobial necrotizing fasciitis in a single center: the emergence of Gram-negative bacteria as a common pathogen.
abstract: BACKGROUND
  Necrotizing fasciitis (NF) is a life-threatening soft tissue infection. It is usually caused by Streptococcus pyogenes and other Gram-positive bacteria. Several reports, however, emphasize the importance of Gram-negative rods in this infection.
  
  
  METHODS
  We retrospectively studied all cases of monomicrobial necrotizing fasciitis hospitalized in our center during the years 2002-2012. We compared clinical characteristics and outcomes of patients with Gram-negative versus Gram-positive infection.
  
  
  RESULTS
  Forty-five cases were reviewed, 19 caused by Gram-negative organisms, 10 of them Escherichia coli, and 26 caused by Gram-positive organisms, 10 of them S. pyogenes. Compared to Gram-positive infections, patients with Gram-negative infections were more likely to have a baseline malignancy (9/19, 47.4%) or to have undergone recent surgery (4/19, 42.3%). The 30-day mortality was higher among Gram-negative infected patients (8/19, 42.1% vs. 8/26, 30.8%). Creatine phosphokinase (CPK) was elevated in a minority of patients with Gram-negative necrotizing fasciitis, and its absolute value was lower than in Gram-positive necrotizing fasciitis.
  
  
  CONCLUSIONS
  In our center, 42% of monomicrobial necrotizing fasciitis cases were found to be caused by Gram-negative organisms, mostly E. coli. These infections usually appeared in immunocompromised or postoperative patients, often presented with normal CPK levels, and were associated with high mortality rates.
authors.affiliation: Infectious Diseases Unit, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel. Electronic address: dafna.yahav@gmail.com.
authors.forename: D
authors.initials: D
authors.lastname: Yahav
authors.affiliation: Department of Medicine F-Recanati, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Duskin-Bitan
authors.affiliation: Infectious Diseases Unit, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: N
authors.initials: N
authors.lastname: Eliakim-Raz
authors.affiliation: Department of Clinical Microbiology, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Ben-Zvi
authors.affiliation: Infectious Diseases Unit, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Shaked
authors.affiliation: Infectious Diseases Unit, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: E
authors.initials: E
authors.lastname: Goldberg
authors.affiliation: Infectious Diseases Unit, Rabin Medical Center, Beilinson Hospital, Petah-Tikva, Israel; Sackler School of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: J
authors.initials: J
authors.lastname: Bishara
mesh_terms: D000328:Adult; D000368:Aged; D004927:Escherichia coli Infections / Q000175:diagnosis / Q000382:microbiology; D019115:Fasciitis, Necrotizing / Q000175:diagnosis / Q000382:microbiology* / Q000401:mortality; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis / Q000382:microbiology* / Q000401:mortality; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000382:microbiology / Q000401:mortality; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies
keywords: Creatine phosphokinase; Escherichia coli; Gram-negative; Necrotizing fasciitis; Soft tissue infection