Clostridium septicum is an anaerobic, motile, spore forming, toxin-producing Gram-positive bacillus (GPB) that has been associated with colon and hematologic malignancies. Despite the low incidence of infection, it is a virulent organism leading to rapidly progressive gas gangrene. Only 51 cases of C. septicum related aortic aneurysms have been reported. 100% mortality is reported in patients without surgical intervention versus 79% undergoing surgery. The primary aim of this study was to determine the incidence and clinical outcomes of patients treated at our institution with C. septicum aortitis.
In this IRB-approved retrospective case series, we reviewed our microbiology laboratorys blood and tissue cultures from January 2005 2018 to identify cases of C. septicum infection. All patients > 18 years of age who had positive cultures were reviewed to provide radiographic or histopathologic correlation.
Among 50 patients with C. septicum in blood and tissue cultures, 7 patients were identified with aortitis. Underlying malignancy was found in 4 cases and included colon cancer (3 cases) and prostate cancer (1 case). The most common location for infection was the infrarenal aorta (4 cases). Previous vascular surgery had been performed in 3 cases. Five of the 7 patients underwent surgical repair with pathology revealing GPB in 3 patients and acute inflammation in the other two patients. C. septicum grew in tissue cultures from these patients. Four of the 7 patients (all of whom underwent surgery) had positive blood cultures. The 2 patients that did not undergo surgery died which is consistent with the 100% mortality described in the literature. All patients were treated with beta-lactam therapy. The median duration among the 5 who completed treatment was 7.5 weeks. Among the 5 patients who underwent surgery, 2 are alive (one at 1 year and another at 5 months post operatively), 2 died within the 1st year after surgery, and 1 patient was lost to follow up.
A small percentage of patients with C. septicum aortitis survived over 1 year. Earlier recognition and emergent surgery with appropriate antimicrobial therapy are needed to improve the outcome of patients diagnosed with this rare infection.
G. Keller, None
S. S. Richter, bioMerieux: Grant Investigator , Research grant . BD Diagnostics: Grant Investigator , Research grant . Roche: Grant Investigator , Research grant . Hologic: Grant Investigator , Research grant . Diasorin: Grant Investigator , Research grant . Accelerate: Grant Investigator , Research grant . Biofire: Grant Investigator , Research grant .
S. J. Rehm, None