Necrotizing soft tissue infection: analysis of the factors related to mortality in 30 cases of a single institution for 5 years

Purpose: Necrotizing soft tissue infection is the infection of the soft tissue with necrotic changes. It is rare, but results in high mortality. We analyzed the characteristics of patients, prognosis, and mortality factors after reviewing 30 cases of a single hospital for 5 years. Methods: From January 2009 to December 2013, 30 patients diagnosed with necrotizing fasciitis or Fournier's gangrene in Pusan National University Hospital were enrolled for this study. The following parameters were analyzed retrospectively: demographics, infection site, initial laboratory finding, initial antibiotics, isolated microorganisms, number of surgeries, time to first operation, length of intensive care unit, and total hospital stays. Results: The overall mortality rate was 23.3%. Mean body mass index (HMI) of the survival group (24.7 +/- 5.0 kg/m(2)) was significantly higher than the nonsurvival group (22.0 +/- 1.4 kg/m(2), P = 0.029). When BMI was less than 23 kg/m(2), the mortality rate was significantly higher (P = 0.025). Two patients (6.7%) with chronic kidney disease requiring hemodialysis died (P = 0.048). Initial WBC count (>13x10(3)/mu L), CRP (>26.5 mg/dL), and platelet (PLT) count (<148x10(3)/mu L) were found to have negative impact on the prognosis of necrotizing soft tissue infection. Factors such as potassium level, blood urea nitrogen (>27.6 mg/dL), serum creatinine (>1.2 mg/dL) that reflected kidney function were significant mortality factors. Conclusion: Patients with low BMI or abnormal values of WBC count, CRP, and PLT count reflecting the degree of infection or abnormal renal function will need more intensive care.