Outcome prediction in patients with Fournier's gangrene

We treated 30 patients with Fournier's gangrene during a 15-year period. Data were collected on demographics, medical history, admission signs and symptoms, physical examination, admission laboratory studies and bacteriology. The timing and degree of surgical débridement as well as antibiotic therapy were also reviewed. The extent of disease was calculated from body surface area nomograms. Data were stratified according to the outcomes of death (13 patients) or survival (17). Patients who survived were significantly younger (53 years old, range 23 to 90) than those who died (71 years old, range 53 to 83, p = 0.004). Admission laboratory parameters that were statistically related to outcome included hematocrit, blood urea nitrogen, calcium, albumin, alkaline phosphatase and cholesterol levels. White blood count, platelets, potassium, bicarbonate, blood urea nitrogen, total protein, albumin and lactic dehydrogenase levels 1 week following hospitalization were also associated with outcome. The greater mean extent of body surface area involved among patients who died was not statistically different from that of those who lived (7.16 and 4.32%, respectively, p = 0.1). The number of surgical débridements did not seem to influence outcome. To assess better the physiological profile of the patients in both outcome categories, the acute physiology and chronic health evaluation II severity score was modified to create a Fournier's gangrene severity index. The mean Fournier's gangrene severity index for survivors was 6.9 +/- 0.9 compared to 13.5 +/- 1.5 for nonsurvivors. Regression analysis demonstrated a strong correlation between Fournier's gangrene severity index and death rate (correlation coefficient = 0.934, p = 0.005). Using a Fournier's gangrene severity index threshold value of 9, there was a 75% probability of death with a score greater than 9, while a score of 9 or less was associated with a 78% probability of survival (p = 0.008). In conclusion, Fournier's gangrene is an infectious disease affecting an ever aging population of patients. Deviation from homeostasis is the most important parameter predictive of outcome and not the extent of disease or performance of surgical débridement. The Fournier's gangrene severity index is an objective and simple method to quantify the extent of metabolic aberration that may be used to predict outcome. We recommend the use of the Fournier's gangrene severity index when evaluating therapeutic options and reporting results.