Mycotic Aneurysm Due to Non-typhi Salmonella: Report of 16 Cases

Abstract

From 1990 through 1994, we collected information on all cases of mycotic aneurysms due to non-typhi Salmonella that occurred at the Veterans General Hospital in Kaohsiung, Taiwan. All cases of salmonella bacteremia were reviewed to find any additional cases. A total of 16 cases of salmonella mycotic aneurysms occurred. The mortality rate was 100% among the three patients treated with medical therapy alone. Nine (70%) of the 13 patients who received surgical and medical therapy survived. Ten of the 16 cases were due to Salmonella choleraesuis. Diagnosis was established by computed tomography or aortography. Gallium scans were of no diagnostic utility. A culture of blood from a patient with underlying atherosclerosis that is positive for invasive Salmonella should prompt a search for a mycotic aneurysm. Treatment with a third-generation cephalosporin and resection of the infected vessel is usually successful.

Isolation of Salmonella enterica serotype choleraesuis resistant to ceftriaxone and ciprofloxacin

“…MR angiography produces images in the transverse, sagittal, and coronal planes, which display the entire thoracic or abdominal aorta in one plane. The availability of these multiple views facilitates the diagnosis of mycotic aneurysm and the determination of its extent and in many cases reveals the presence of branch vessel involvement (27,131,150). Figure 2 shows an MR angiogram of a patient with a mycotic aneurysm at the infrarenal portion of the abdominal aorta.…”

“…Mycotic aneurysm caused by Salmonella was almost uniformly fatal in previous times; however, multiple publications of case reports and case series found that early surgical intervention has greatly increased survival (3,27,63,105,131,142,150). Most surgeons consider the excision of an infected vessel with extra-anatomic vascular reconstruction to be the surgery of choice for abdominal mycotic aneurysm (142).…”

“…Most surgeons consider the excision of an infected vessel with extra-anatomic vascular reconstruction to be the surgery of choice for abdominal mycotic aneurysm (142). In addition, a prolonged course of antibiotics (for 6 weeks or longer) is indicated (3,40,150). A recent review of 136 evaluable cases in patients seen from 1948 through 1999 found a 62% survival rate (38% mortality) for all such patients treated with combined surgical and medical therapy (131).…”

“…Overall, around 30% of the reported patients was infected by serotype Typhimurium and 15% each were infected by serotypes Enteritidis and Choleraesuis (131). Interestingly, the reports of a relatively high incidence of serotype Choleraesuis infection came mostly from Taiwan (27,150). In Taiwan, serotype Choleraesuis was the second most common serotype among all Salmonella serotypes isolated and showed the greatest ability to cause extraintestinal infections (32,33).…”

“…It is also important to search for endovascular abnormalities by using imaging techniques in older patients with or without evidence of atherosclerosis. Although there is no consensus on the optimal duration of postoperative antibiotic therapy for endovascular infections caused by Salmonella, most investigators still recommend a minimum of 6 weeks (3,39,40,150). The duration of therapy for other extraintestinal infections should be considered based on the site of infection.…”