Necrotizing fasciitis: risk factors of mortality

Patcharin Khamnuan,1,2 Wilaiwan Chongruksut,3 Kijja Jearwattanakanok,4 Jayanton Patumanond,5 Suttida Yodluangfun,6 Apichat Tantraworasin31Clinical Epidemiology Program, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; 2Department of Nursing, Phayao Hospital, Phayao, Thailand; 3Department of Surgery, Faculty of Medicine, Chiang Mai University, Chiang Mai, Thailand; 4Department of Surgery, Nakornping Hospital, Chiang Mai, Thailand; 5Clinical Epidemiology Unit, Clinical Research Center, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand; 6Department of Nursing, Chiangrai Prachanukroh Hospital, Chiang Rai, ThailandBackground: Necrotizing fasciitis (NF) is a serious infection of skin and soft tissues that rapidly progresses along the deep fascia. It becomes a fatal soft tissue infection with high mortality rate if treatment is delayed. Early diagnosis for emergency surgical debridement and broad-spectrum antibiotic therapy were the optimal treatments to reduce the mortality rate of NF.Objective: The aim of this study was to identify risk factors that increased the mortality rate in patients with NF under routine clinical practices.Methods: A retrospective cohort study was performed at three general hospitals located in northern Thailand. All medical records of patients with surgically confirmed NF treated between January 2009 and December 2012 were reviewed. Clinical predictors for mortality were analyzed using multivariable risk regression analysis.Results: Of a total of 1,504 patients with a diagnosis of NF, 19.3% (n=290) died in hospital and 80.7% (n=1,214) survived. From multivariable analysis, being female (risk ratio [RR] =1.37, 95% confidence interval [CI] =1.01–1.84); age >60 (RR =1.39, 95% CI =1.25–1.53); having chronic heart disease (RR =1.64, 95% CI =1.18–2.28), cirrhosis (RR =2.36, 95% CI =1.70–3.27), skin necrosis (RR =1.22, 95% CI =1.15–1.28), pulse rate >130/min (RR =2.26, 95% CI =1.79–2.85), systolic BP <90 mmHg (RR =2.05, 95% CI =1.44–2.91), and serum creatinine ≥1.6 mg/dL (RR =3.06, 95% CI =2.08–4.50) were risk factors for mortality.Conclusion: Prognostic factors for mortality in NF patients included being female; age >60; or having chronic heart disease, cirrhosis, skin necrosis, pulse rate >130/min, systolic BP <90 mmHg, and serum creatinine ≥1.6 mg/dL. Thus, disease progression to mortality may occur in such patients presenting one of these risk factors. Further examination or close monitoring for systemic involvement may be advantageous to reduce morbidity and mortality.Keywords: clinical predictors, risk factor, mortality, necrotizing fasciiti