title: The Prediction Predicament: Rethinking Necrotizing Soft Tissue Infections Mortality.
abstract: BACKGROUND
  Our study sought to identify independent risk factors predisposing patients with necrotizing soft tissue infections (NSTIs) to mortality from among laboratory values, demographic data, and microbiologic findings in a small population. To this end, a retrospective review was conducted of the medical records of all patients with NSTI who had been treated at our institution from 2003 to 2012 (n=134).
  
  
  METHODS
  Baseline demographics and comorbidities, clinical and laboratory values, hospital course, and the microbiologic characteristics of surgical incision cultures were recorded. Each variable was tested for association with survival status and all associated variables with p<0.15 were included in a logistic regression model to seek factors associated independently with mortality.
  
  
  RESULTS
  Surprisingly, no demographic or pre-existing condition proved to be a predictor of mortality. Two laboratory values had an inverse correlation to mortality: High C-reactive protein (CRP) and highest recorded CRP. Of surgical incisions that grew bacteria in culture, 33.6% were polymicrobial. Mortality rates were highest with Enterococcus-containing polymicrobial infections (50%), followed by those containing Pseudomonas (40%), and Streptococcus spp. (27%). Understanding why so many studies across the literature, now including our own, find such disparate results for correlation of NSTI mortality with patient data may lie in the fundamentally dynamic nature of the organisms involved.
  
  
  CONCLUSIONS
  This study suggests that no single factor present on admission is a robust predictor of outcome; it is likely that survival in NSTI is predicated upon a complex interaction of multiple host and microbial factors that do not lend themselves to reduction into a simple formula. It is also abundantly clear that the well-established principles of NSTI surgery should continue to be followed in all cases, with an emphasis on early debridement, irrespective of apparent severity of initial presentation.
authors.affiliation: 1 Department of Surgery, Texas Tech University Health Sciences Center , Lubbock, Texas.
authors.forename: Samantha A
authors.initials: SA
authors.lastname: Moore
authors.affiliation: 1 Department of Surgery, Texas Tech University Health Sciences Center , Lubbock, Texas.
authors.forename: Brandon H
authors.initials: BH
authors.lastname: Levy
authors.affiliation: 2 Department of Mathematics and Statistics, Texas Tech University , Lubbock, Texas.
authors.forename: Chalani
authors.initials: C
authors.lastname: Prematilake
authors.affiliation: 1 Department of Surgery, Texas Tech University Health Sciences Center , Lubbock, Texas.
authors.forename: Sharmila
authors.initials: S
authors.lastname: Dissanaike
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002648:Child; D019115:Fasciitis, Necrotizing / Q000401:mortality*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D012307:Risk Factors; D018461:Soft Tissue Infections / Q000401:mortality*; D016019:Survival Analysis; D055815:Young Adult