Clinical predictors for severe sepsis in patients with necrotizing fasciitis: an observational cohort study in northern Thailand

Patcharin Khamnuan,1,2 Wilaiwan Chongruksut,3 Kijja Jearwattanakanok,4 Jayanton Patumanond,5 Apichat Tantraworasin,3 1Clinical 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, 4Department of Surgery, Nakornping Hospital, Chiang Mai, Thailand; 5Clinical Epidemiology Unit, Clinical Research Center, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand Background: Necrotizing fasciitis (NF) is a life-threatening infection of skin and fascia. Its progress is extremely fast, with extensive necrosis. Delay in treatment, with subsequent huge soft tissue loss and associated severe sepsis, remains a major cause of death in the management of NF. Objective: The aim of this study was to explore clinical characteristics that may be used to predict severe sepsis in patients with NF, in the context of routine clinical practice in northern Thailand. Methods: A retrospective observational cohort study was conducted. The patient cohort in this study consisted of all patients who were diagnosed with NF by surgical or pathological confirmation. The follow-up period started with the admission date and ended with the discharge date. The clinical variables were collected from patients registered at three provincial hospitals in northern Thailand from 2009 to 2012. The clinical predictors for severe sepsis were analyzed using multivariable risk regression. Results: A total of 1,452 patients were diagnosed with NF, either with severe sepsis (n=237 [16.3%]) or without severe sepsis (n=1,215 [83.7%]). From the multivariable analysis, female sex (relative risk [RR] =1.51; 95% confidence interval [CI] =1.04–2.20), diabetes mellitus (RR =1.40; 95% CI =1.25–1.58), chronic heart disease (RR =1.31; 95% CI =1.15–1.49), hemorrhagic bleb (RR =1.47; 95% CI =1.32–1.63), skin necrosis (RR =1.45; 95% CI =1.34–1.57), and serum protein <6 g/dL (RR =2.67; 95% CI =1.60–4.47) were all predictive factors for severe sepsis. Conclusion: The clinical predictors for severe sepsis in patients with suspicion of NF included female sex, diabetes mellitus, chronic heart disease, hemorrhagic bleb, skin necrosis, and serum protein ,6 d/dL. The risk ratio was much higher in patients with total protein <6 g/dL, which is associated with malnutrition. Therefore, provision of sufficient nutritional support and close monitoring for these clinical predictors may be beneficial to reduce morbidity and mortality. Keywords: Necrotizing fasciitis, severe sepsis, clinical predictor

Necrotizing fasciitis: epidemiology and clinical predictors for amputation

Patcharin Khamnuan,1,2 Wilaiwan Chongruksut,3 Kijja Jearwattanakanok,4 Jayanton Patumanond,5 Apichat Tantraworasin3 1Clinical Epidemiology Program, Faculty of Medicine, Chiang Mai University, Chiang Mai, 2Department of Nursing, Phayao Hospital, Phayao, 3Department of Surgery, Faculty of Medicine, Chiang Mai University, 4Department of Surgery, Nakornping Hospital, Chiang Mai, 5Clinical Epidemiology Unit, Clinical Research Center, Faculty of Medicine, Thammasat University, Pathum Thani, Thailand Background: Necrotizing fasciitis, a relatively uncommon infection involving the skin, subcutaneous tissue, and fascia, is a rapidly progressive soft tissue infection and a medical and surgical urgency. Delayed debridement, with subsequent huge soft tissue loss is associated with loss of limb and infection and is the most common cause of mortality. The purpose of this work is to describe the epidemiology of necrotizing fasciitis and to identify the clinical characteristics that may be used to predict amputation in routine clinical practice. Methods: Retrospective cohort study data were collected from three general hospitals located in the Chiang Rai, Kamphaeng Phet, and Phayao provinces in northern Thailand. Epidemiologic data for all patients with a surgically confirmed diagnosis of necrotizing fasciitis between 2009 and 2012 were collected. Medical records and reviews were retrieved from inpatient records, laboratory reports, and registers. Clinical predictors for amputation were analyzed by multivariable risk regression. Results: A total of 1,507 patients with a diagnosis of necrotizing fasciitis were classified as being with amputation (n=127, 8.4%) and without amputation (n=1,380, 91.6%). The most common causative Gram-positive and Gram-negative pathogens were Streptococcus pyogenes (33.3% in the amputation group and 40.8% in the non-amputation group) and Escherichia coli (25% in the amputation group and 17.1% in the non-amputation group). Predictive factors for amputation included gangrene (risk ratio [RR] 4.77, 95% confidence interval [CI] 2.70–8.44), diabetes mellitus (RR 3.08, 95% CI 1.98–4.78), skin necrosis (RR 2.83, 95% CI 2.52–3.18), soft tissue swelling (RR 1.76, 95% CI 1.24–2.49), and serum creatinine values ≥1.6 mg/dL on admission (RR 1.71, 95% CI 1.38–2.12). All data were analyzed using the multivariable risk regression generalized linear model. Conclusion: The most causative pathogens were S. pyogenes and E. coli. Clinical predictors for amputation in patients with necrotizing fasciitis included having diabetes mellitus, soft tissue swelling, skin necrosis, gangrene, and serum creatinine values ≥1.6 mg/dL on admission. Thus, patients with any of these predictors should be monitored closely for progression and receive early aggressive treatment to avoid limb loss. Keywords: necrotizing fasciitis, clinical predictors, amputatio

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