A disproportionate number of patients with Fournier's gangrene were treated at a relatively small group of teaching hospitals. Less than 18% of the 1,720 hospitals analyzed were considered teaching hospitals but 57% of Fournier's gangrene cases were managed at these hospitals. In contrast, patients with Fournier's gangrene were treated at only 30% of nonteaching hospitals (p <0.0001). Patients treated at teaching hospitals were more acutely ill and required more surgical procedures (especially genital/perineal débridement), more mechanical ventilation and other supportive care, likely accounting for the longer stay, greater hospital charges and higher mortality rate.
In this population based study increasing patient age was the strongest independent predictor of mortality (aOR 4.0 to 15.0, p <0.0001). Patients treated at hospitals where more individuals with Fournier's gangrene were treated had 42% to 84% lower mortality than hospitals where only 1 patient per year was treated after adjusting for other important patient and hospital factors (p <0.0001). This may reflect more aggressive diagnosis of and management for Fournier's gangrene at more experienced hospitals. Patients admitted via transfer were also at higher independent risk for death (aOR 1.9). This may reflect more severe illness in transferred patients, lack of critical care facilities at transferring hospitals, or delayed management. These findings support increased regionalization of care for patients with Fournier's gangrene. Because patients often require care from urological surgeons, general surgeons, intensivists and plastic surgeons, a multidisciplinary approach provided at facilities where there is greater experience may improve patient outcomes.
Patients treated at teaching hospitals had a higher mortality rate (aOR 1.9). This may reflect differences in severity, management or supportive care, or diagnostic criteria for Fournier's gangrene at teaching hospitals may differ from criteria at nonteaching hospitals. After adjusting for the number of surgeries required by a patient during hospitalization teaching center status as a marker of disease severity was not an independent predictor of death. Higher mortality at teaching hospitals likely reflects a more severely ill population. Patient race and other hospital related factors assessed, including site, size, ownership and United States region, did not independently predict mortality.
Death tended to occur late during hospitalization. Patients who died had slightly longer median length of stay and greater hospital charges (median $40,871 vs $26,574, p = 0.0001). These findings may reflect a more indolent course of Fournier's gangrene after initial therapy in severely ill patients. Death may also reflect in hospital complications but we have no data on these events.
The Charlson comorbidity index performed well in this patient population. However, congestive heart failure, renal failure and coagulopathy added significantly to the comorbidities characterized in the Charlson index. Future studies of the mortality risk in patients with Fournier's gangrene should consider providing additional attention to these comorbidities.
The morbidity rate due to Fournier's gangrene was high. As in other reports, patients often required many operations, especially genital/perineal débridement, orchiectomy, cystostomy and/or colostomy.19-22
Overall 30% of survivors required ongoing care after hospital discharge. Given the rarity of surgical wound closure (7%) during the initial hospitalizations evaluated, ongoing care was necessary to facilitate open wound closure in many cases.
This study has important limitations. We did not have access to important clinical, laboratory or microbiological culture data so that we could not determine infection severity by skin surface area involvement or evaluate the performance of the Fournier's Gangrene Severity Index in our large patient cohort. The number of distinct visits to the operating room were determined in 61% of cases, potentially limiting use of this variable as a marker of disease severity. Data collection was retrospective, involving administrative data. Differential morbidity coding, coding errors or misclassifications are possible. The ICD-9 code for Fournier's gangrene (608.83) is found under the diseases of the male genital organs subheading and no comparable diagnosis code exists for females. Thus, our search strategy did not identify females with Fournier's gangrene.
To our knowledge we provide the first comparison of outcomes in patients treated at different hospital types and the first population based study of predictors of death. Findings support earlier observations from tertiary care referral centers documenting the frequent need for surgical procedures and supportive care. The large number of cases identified provided a unique opportunity to identify patient and hospital associated factors predictive of mortality.