Prognostic factors and monomicrobial necrotizing fasciitis: gram-positive versus gram-negative pathogens

Abstract

BackgroundMonomicrobial necrotizing fasciitis is rapidly progressive and life-threatening. This study was undertaken to ascertain whether the clinical presentation and outcome for patients with this disease differ for those infected with a gram-positive as compared to gram-negative pathogen.MethodsForty-six patients with monomicrobial necrotizing fasciitis were examined retrospectively from November 2002 to January 2008. All patients received adequate broad-spectrum antibiotic therapy, aggressive resuscitation, prompt radical debridement and adjuvant hyperbaric oxygen therapy. Eleven patients were infected with a gram-positive pathogen (Group 1) and 35 patients with a gram-negative pathogen (Group 2).ResultsGroup 2 was characterized by a higher incidence of hemorrhagic bullae and septic shock, higher APACHE II scores at 24 h post-admission, a higher rate of thrombocytopenia, and a higher prevalence of chronic liver dysfunction. Gouty arthritis was more prevalent in Group 1. For non-survivors, the incidences of chronic liver dysfunction, chronic renal failure and thrombocytopenia were higher in comparison with those for survivors. Lower level of serum albumin was also demonstrated in the non-survivors as compared to those in survivors.ConclusionsPre-existing chronic liver dysfunction, chronic renal failure, thrombocytopenia and hypoalbuminemia, and post-operative dependence on mechanical ventilation represent poor prognostic factors in monomicrobial necrotizing fasciitis. Patients with gram-negative monobacterial necrotizing fasciitis present with more fulminant sepsis.

Unusual “Flesh-Eating” Strains of Escherichia coli

“…We could not identify possible predisposing factors leading to the E. coli infection, i.e., receiving Gram-positive active antibiotics prior to the presentation. The reported incidence of E. coli as a monomicrobial pathogen resulting in necrotizing fasciitis is very rare, ranging from 0 to 10% (1,6,11,12). Chen et al (4) reported on 126 patients with a single etiologic agent causing necrotizing fasciitis.…”

“…Among Gram negatives, Vibrio vulnificus and Aeromonas hydrophila are well-known causative agents of monomicrobial necrotizing fasciitis (12). E. coli has been isolated from polymicrobial or Fournier's gangrene, but has rarely been reported in monomicrobial necrotizing fasciitis (8).…”

Necrotizing Fasciitis: A Study of 48 Cases

“…Diabetic neuropathy further increases the risk of injuries, which are very often the triggering factors in cases of necrotizing fasciitis. Pre-existing chronic liver dysfunction, chronic renal failure, thrombocytopenia, hypoalbuminemia, and postoperative dependence on mechanical ventilation represent poor prognostic factors in monomicrobial necrotizing fasciitis [14].…”

Predictors of Monomicrobial Necrotizing Soft Tissue Infections

“…Interestingly, other prior studies have shown that there is no difference in the mortality rates of gram-positive pathogens (9.09%) and gramnegative pathogens (17.14%; p = 1.00) in monomicrobial infections, suggesting that S. pyogenes is no more virulent in necrotizing infections than are organisms such as E. coli or B. fragilis [38].…”