The spectrum of cardiovascular infections due to Salmonella enterica: a review of clinical features and factors determining outcome

Management of the infected aortoiliac aneurysms

PURPOSE

We have reviewed ruptured and nonruptured infected aortoiliac aneurysms to study the clinical presentation, management and eventual outcome of patients managed with in situ prostheses, axillofemoral prostheses grafts and endovascular reconstruction.

DESIGN

A retrospective chart review of 16 cases treated at a single institution.

METHODS

From January 2007 to March 2008, a total of 93 patients with aortoiliac aneurysms underwent surgical repair at our institution. Among these, 16 patients (17.2%) were shown to be infected aneurysms of the infrarenal (n = 6), juxtarenal (n = 2), and pararenal aorta (n = 1); the others were 5 common, 1 external, and 1 internal iliac arteries. Fourteen patients were male and 2 were female with the mean age of 66 years (range, 45-79). In all cases, the diagnosis was confirmed by abdominal computed tomography and empirical parenteral antibiotics were administered at least 1 week, unless in patients need emergency operations. At the time of an operation, all were saccular and were classified as primary infected aortoiliac aneurysms. Thirteen patients had surgical debridement with in situ graft interposition and omental wrapping, 2 underwent aneurysm exclusion and extra-anatomic (axillo-femoral) bypass, 1 underwent aneurysmectomy of left external iliac artery and polytetrafluoroethylene (PTFE) graft interposition, and 1 underwent endovascular exclusion. The parenteral antibiotics were continued in the postoperative period for 4-6 weeks. Chronic renal disease was present in 37.5% (6/16), with diabetes mellitus present in 31.25% (5/16). The most common pathogen was Salmonella sp. (n = 6) and E. coli (n = 5). Thirty-seven percent (6/16) of the patients presented late, with a 37.5% (6/16) incidence of ruptured (4 contained, 2 free ruptured) that needed emergency surgery.

RESULTS

Disease-specific mortality was 31.25% (5/16). The 30-day mortality rate of ruptured cases is high 67% (4/6), because patients present late in the course of the disease. One patient who underwent aneurysm exclusion and extra-anatomic (axillo-femoral) bypass died 6 months later from burst aortic stump. Salmonella and E. coli are the most common pathogens.

CONCLUSIONS

Early diagnosis followed by surgical intervention with proper antibiotic coverage provides the best results. Mortality rate was still high in patients with sepsis and rupture. An in situ graft interposition and omental wrapping is a safe option for revascularization of infected aneurysms of the iliac arteries and infrarenal aorta.

Predictors for pathologically confirmed aortitis after resection of the ascending aorta: a 12-year Danish nationwide population-based cross-sectional study

Introduction

Assessing the prevalence of, and predictors for, pathologically-confirmed inflammation of the aorta in Denmark, using a nationwide population-based study design.

Methods

We identified all adults with first-time surgery on the ascending aorta between January 1, 1997 and March 1, 2009 in Denmark. Presence of aortic inflammation was ascertained through linkage to a nationwide pathology registry. We used logistic regression to compute prevalence odds ratios (ORs) for sex, age at surgery, cardiovascular risk factors, cancer, connective tissue disease, and infectious diseases associated with the presence of aortitis.

Results

A total of 1,210 adults underwent resection of the ascending aorta, of who 610 (50.4%) had tissue submitted for pathological examination. Aortitis was found in 37 (6.1%) patients whose tissue was examined. Ten of the 37 patients were diagnosed with conditions known to be associated with aortitis or aortic aneurysm: five patients with temporal arteritis, one with Crohn's disease, one with rheumatoid arthritis, one with systemic lupus erythematosus, one with infectious aortitis, and one with Marfan's disease. Twenty-seven patients had idiopathic aortitis. Predictors of aortitis included history of connective tissue disease (adjusted OR 4.7, 95% confidence interval (CI) 1.6, 13.6), diabetes (OR 5.2, 95% CI 0.9, 29.7), advanced age (> 67 years OR 2.5, 95% CI 0.8, 7.6), and aortic valve pathology (OR 2.3, 95% CI 1.1, 4.9).

Conclusions

Aortitis was present in 6.1% of adults in Denmark who had pathological examination after resection of the ascending aorta. Predictors of inflammation included connective tissue disease, diabetes, advanced age, and aortic valve pathology.

Management of Gram-negative and fungal endocarditis

Infective endocarditis is infrequently caused by Gram-negative bacteria or fungi. Gram-negative organisms are responsible for <4% of cases, whilst fungal endocarditis accounts for <1.5% of culture-positive cases worldwide. Endocarditis due to Gram-negative organisms or fungi is a rare but severe disease. It often has a nosocomial origin, is caused by virulent and often resistant organisms and presents a high rate of complications and high mortality. In this article we present the most recent literature data and address the current management of Gram-negative and fungal infective endocarditis. We also discuss the major challenges of antimicrobial treatment and discuss some issues related to surgical decision-making in difficult-to-manage cases. We finally present our centre's experience with Gram-negative infective endocarditis, with a special focus on the demanding issues that the management of these complex and severely ill patients raise.

An infected abdominal aortic aneurysm due to non-typhoidal Salmonella in an HIV-1-infected Japanese patient

We herein report a case study of an HIV-1-infected 64-year-old Japanese man who presented, with an abdominal aortic aneurysm due to non-typhoidal Salmonella. He was admitted with a 7-day history of intermittent left back pain. A culture of a blood specimen yielded gram-negative bacilli, which were identified as non-typhoidal Salmonella. Computed tomography showed an abdominal aortic aneurysm due to the non-typhoidal Salmonella infection. Since such a complication is frequently fatal, its management, especially the timing of surgery, is difficult. Further studies are needed to determine the optimal treatment strategy, however, early diagnosis and prompt careful treatment can reduce mortality.

Infective endocarditis caused by Salmonella enteritidis in a dialysis patient: a case report and literature review

Background

Infective endocarditis is significantly more common in haemodialysis patients as compared with the general population, the causative pathogen is generally Staphylococcus aureus; there have been no previously reported cases of infective endocarditis caused by a Salmonella species in haemodialysis patients.

Case Presentation

We report the case of a 68 year-old woman on haemodialysis who developed infective endocarditis as a result of Salmonella enteritidis. Although we treated the patient with ceftriaxone combined with ciprofloxacin, infective endocarditis was not detected early enough and unfortunately developed into cerebral septic emboli, which ultimately resulted in death.

Conclusion

Although there are several reports that Salmonella endocarditis without cardiac failure can be successfully treated with antibiotics alone, early surgical intervention is essential for some cases to prevent life-threatening complications. Transesophageal echocardiography should be performed in any patient with high clinical suspicion of infective endocarditis. To the best of our knowledge, this is the first case-report of Salmonella endocarditis in a haemodialysis patient.

Endovascular repair of mycotic aneurysms of the aorta: An alternative to conventional bypass surgery in patients with acute sepsis

Treatment of mycotic aneurysms of the aorta includes excision of infected tissue followed by anatomic or extra-anatomic bypass. However, operative mortality remains high particularly in elderly patients with comorbidities. We describe here 2 patients with mycotic aneurysms of the descending aorta in whom endovascular repair was successfully performed. In 1 of these patients, stent grafting was attained during the acute, bacteraemic phase of infection. After 12 and 20 months, respectively, of diagnosis, both patients are doing well.

Simultaneous Salmonella spp. endocarditis and mycotic abdominal aortic aneurysm presentation: a surgical dilemma

Concomitant valvular and abdominal aortic pathologies, both requiring urgent surgical interventions, are an uncommon entity. The ideal surgical management of such a scenario varies, depending on a host of variables. Due to its complexity and rarity, the ideal management approach remains an unknown. We describe a patient who presents with a delayed diagnosis of concomitant Salmonella species mitral valve (MV) endocarditis and mycotic abdominal aortic aneurysm (AAA). Though both clinical entities required urgent surgical intervention, the presence of one made intervening for the other high-risk and created a surgical dilemma. Following guarded conservative medical management, the patient underwent successful staged surgical interventions.

Endovascular treatment of septic thrombophlebitis: a case report of a rare complication and review of the literature

We report a case of severe deep venous thrombosis (DVT) treated with multimodality therapy that was complicated by sepsis due to thrombus likely infected by Salmonella virchow. We review the current therapeutic options in the therapy of severe DVT and cardiovascular pathology associated with non-typhoid Salmonella.

Extensive Salmonella enteritidis endocarditis involving mitral, tricuspid valves, aortic root and right ventricular wall

After conducting a PubMed search, 11 articles describing a total of 12 cases of native valve Salmonella enteritidis (S. enteritidis) endocarditis were identified in the English literature. Only 13 cases of prosthetic valve endocarditis attributed to S. enteritidis have been published in the English literature. Only 1 case involving the myocardium and other valves concomitantly could be located. Transthoracic echocardiography proved inadequate to demonstrate valvular vegetations. Transesophageal echocardiography was instrumental in establishing the diagnosis of endocarditis by documenting vegetations. S. enteritidis endocarditis can cause devastating endovascular infections in immunocompromised patients. Patients who present with multiple vague symptoms with medical histories that include diabetes mellitus, immunocompromise, and prosthetic heart valves should alert clinicians to strongly consider S. enteritidis endocarditis in their differential diagnoses. Despite considerable effort, S. enteritidis endocarditis poses very high risk for morbidity and mortality.

Short- and long-term effects of bacterial gastrointestinal infections

Bacterial gastrointestinal infections are associated with short- and long-term complications from several organ systems.

During 1997–2004, microbiologically confirmed gastrointestinal infections were reported for 101,855 patients in Sweden. Among patients who had Salmonella infection (n = 34,664), we found an increased risk for aortic aneurysm (standardized incidence ratio [SIR] 6.4, 95% confidence interval [CI] 3.1–11.8) within 3 months after infection and an elevated risk for ulcerative colitis (SIR 3.2, 95% CI 2.2–4.6) within 1 year after infection. We also found this elevated risk for ulcerative colitis among Campylobacter infections (n = 57,425; SIR 2.8, 95% CI 2.0–3.8). Within 1 year, we found an increased risk for reactive arthritis among patients with Yersinia enteritis (n = 5,133; SIR 47.0, 95% CI 21.5–89.2), Salmonella infection (SIR 18.2, 95% CI 12.0–26.5), and Campylobacter infection (SIR 6.3, 95% CI 3.5–10.4). Acute gastroenteritis is sometimes associated with disease manifestations from several organ systems that may require hospitalization of patients.

Bacteraemia due to non-typhoidal Salmonella in Thailand: clinical and microbiological analysis

The prevalence of non-typhoidal Salmonella (NTS) bacteraemia has risen in many countries and is probably related to the increase in HIV infection. There is little information regarding NTS bacteraemia in Thailand, where the HIV infection rate increased 13.6-fold during the period 1992-2004. This study aimed at surveying the prevalence as well as analysing the clinical and microbiological features of NTS bacteraemia at a large university hospital in Thailand. Patients with positive blood cultures for NTS during 2005 were retrospectively reviewed for their demographics, underlying diseases and microbiological profiles. A total of 135 patients had NTS bacteraemia. Salmonella group C was predominant. The most common underlying disease was HIV infection. Up to 30% of NTS isolates were identified as multidrug resistant. This study should prompt an alert regarding the evolving pattern of NTS bacteraemia in Thailand.

A Case Report of Endovascular Stenting in Salmonella Mycotic Aneurysm: A Successful Procedure in an Immunocompromised Patient

Introduction: Mycotic aneurysms are associated with high mortality rates and are managed in the local setting with extra-anatomical bypass followed by ligation, exclusion and debridement of the aneurysm. This is the first case of successful endovascular stenting in an immunocompromised patient with Salmonella mycotic aneurysm. Clinical Picture: A middle-aged man who was HIV positive had Salmonella septicaemia. He developed abdominal pain 5 days after admission and a computed tomography (CT) scan of the abdomen revealed infrarenal aortitis. He developed a mycotic aneurysm 3 weeks later. Treatment: He opted for endovascular stenting and after prolonged antibiotic therapy and negative blood cultures, he underwent the procedure using a TalentTM stent, with an iliac extension. Outcome: He was discharged 1 week after stenting and maintained on oral bactrim based on sensitivity. At 1-year follow-up, he remains well symptomatically and CT scan showed no endoleak or collection. Conclusion: Endovascular stenting, though a fairly new procedure, can be successfully deployed even in a mycotic aneurysm in the right setting. Key words: Aortitis, Aortic aneurysm, Endovascular stenting, Salmonella enteriditis

High incidence of intravascular focus in nontyphoid Salmonella bacteremia in the age group above 50 years: a population-based study

Questions regarding the relative frequency of vascular complications in nontyphoid Salmonella bacteremia are pending, and the true population-based age-related incidence is not known. We reviewed all cases of nontyphoid Salmonella bacteremia during a 10-year period from 1994 through 2003 in a well-defined population of 492,843 residents in North Jutland County, Denmark. 77 of a total of 111 cases occurred in patients >50 years old. In this age group, five cases of mycotic aneurysm and two cases of endocarditis were documented, corresponding to a 9% occurrence. The annual incidence rate of endovascular nontyphoid Salmonella infection in this age group was 4.4 per 1,000,000 person years. The mortality was 43% in cases with endovascular infection, and surgical procedures were important for survival. We conclude that in patients older than 50 years, detection of nontyphoid Salmonella bloodstream infection should be followed by examinations for mycotic aneurysms and endocarditis.

[Thoracic infectious aortitis: microbiology, pathophysiology and treatment]

BACKGROUND

Thoracic infectious aortitis are currently rare. They are always lethal without any treatment. The microorganisms involved are numerous with particular pathophysiological characteristics for each bacterium. Treatment is difficult and must associate medical and surgical care.

RECENT FINDINGS

Bacterial epidemiology of infectious aortitis has been profoundly modified with the large use of antibiotics. Syphilitic aortitis were frequent in the beginning of the twentieth century but its incidence has dramatically fallen. It still exists and its clinical presentation must be known to begin an adequate treatment. Other bacterial aetiologies of these aortitis are more classical with high frequencies of Staphylococcus aureus and Streptococcus, which are often associated with infective endocarditis. Among Gram-negative bacteria, Salmonella spp are the most frequently met microorganisms. Atherosclerosis represents the principal risk factor of these infectious aortitis. It provokes arterial parietal damage useful for bacterial attach. A saccular aneurysm of infective origin can then appear. Treatment must consist on antibiotics before surgery; Tuberculous aortitis are also possible but are much more rare.

CONCLUSION

Thoracic infectious aortitis are very rare but must be known because of their poor prognosis. Treatment is difficult and prevention of atherosclerosis which is the most important risk factor of these diseases is therefore of greatest importance.

Bacteraemia due to ciprofloxacin-resistant Salmonella enterica serotype Choleraesuis in adult patients at a university hospital in Taiwan, 1996-2004

Eighty-one adult patients with Salmonella enterica serotype Choleraesuis (S. Choleraesuis) bacteraemia treated at a university hospital from 1996 to 2004 were evaluated. Multivariate analysis with a logistic regression model was used to characterize risk factors for primary bacteraemia and mycotic aneurysm and to determine the association of clinical characteristics of patients based on ciprofloxacin susceptibility of the causative organism. The incidence per 100,000 discharges was 0.76 in 1996 and 3.9 in 2004. The overall rate of ciprofloxacin resistance among these isolates was 59% (87 isolates) and the annual rate increased with time from 0% prior to 2000 to 80% in 2004. Among these patients, 48 (59%) had primary bacteraemia and 13 (16%) had secondary bacteraemia with mycotic aneurysm. Seventy (86%) patients had fever at presentation, 22 (27%) developed shock during hospitalization, and eight (10%) died of S. Choleraesuis bacteraemia. Patients with immunocompromised conditions had a higher risk of developing primary bacteraemia (OR 18.442, P < 0.001). Hypertension (OR 15.434, P = 0.002) and male gender (OR 7.422, P = 0.039) were associated with mycotic aneurysm. Patients with mycotic aneurysm were more frequently infected with ciprofloxacin-susceptible isolates (P = 0.028) and ciprofloxacin-susceptible isolates were also more frequently associated with recurrent infection than ciprofloxacin-resistant isolates (P = 0.038). The incidence of S. Choleraesuis bacteraemia has increased in the past 8 years, and this increase is associated with the upsurge of ciprofloxacin-resistant isolates.

Abdominal aortic mycotic aneurysm, psoas abscess, and aorto-bisiliac graft infection due to Salmonella typhimurium

Infections due to nontyphoidal Salmonella are common and their incidence has been increasing in the last few years. Here, we describe a patient with a rupture of abdominal aortic aneurysm associated with a psoas abscess due to Salmonella typhimurium. Early diagnosis, prompt surgical intervention, and active and prolonged antibiotic therapy are the gold standard for the management of this severe clinical situation.

Ten-year experience with surgical repair of mycotic aortic aneurysms

BACKGROUND

Mycotic aneurysm remains a lethal pathologic entity, especially when rupture occurs. It may result from primary aortitis, be induced by septic emboli, or be secondary to an adjacent infection, such as pancreatitis or a psoas muscle abscess. Surgical intervention is the only way to treat such disease. Even when successful repair is achieved by insertion of an interposition in situ graft or by performance of an extra-anatomic bypass, the prognosis is poor. The aim of this study was to present our experience of managing mycotic aortic aneurysms during the past 10 years.

METHODS

From January 1994 to June 2004, a total of 734 patients with aortic aneurysms underwent surgical repair at our institution. Among these cases, 17 (2.3%) were shown to be mycotic aneurysms of the ascending aorta (n = 1), aortic arch (2), thoracic and thoracoabdominal aorta (3), or abdominal aorta (11); 14 patients (mean age, 58.8 years) were male. Preoperative imaging studies were performed in all patients. Mycotic aortic aneurysms were suspected in 12 of the 17 patients (70.6%) preoperatively, and 4 of these 12 patients were found to have ruptures on imaging. At the time of surgery, 9 of the 17 aneurysms (52.9%) were ruptured. Fifteen patients had an interposition graft inserted after meticulous debridement, 1 underwent an aorto-aortic bypass, and 1 underwent an extra-anatomic (axillo-femoral) bypass. An omentum patch was applied to wrap the graft in 8 of 11 mycotic aortic aneurysms of the abdominal aorta. The most common pathogens were Salmonella spp. (n = 7) and Staphylococcus spp. (4). All patients received antibiotic therapy, according to the culture report, for about 4-6 weeks postoperatively.

RESULTS

In-hospital mortality was 11.8% (n = 2). Another patient died from massive upper gastrointestinal bleeding 6 months after operation because of complications involving an aorto-duodenal fistula, and another died from stomach cancer 6 years after surgery. Long-term follow-up (mean, 37 months; range, 3-111 months) revealed that, at the time of writing, the remaining 13 patients were alive and well, without any recurrence of aneurysm.

CONCLUSION

Mycotic aneurysm of the aorta is a life-threatening disease, especially when rupture occurs. The high mortality rate is due not only to the high rupture rate, but also to sepsis. When mycotic aortic aneurysm is diagnosed, early surgical intervention is mandatory.

Influence of ciprofloxacin resistance on risk factors for endovascular infection in patients with infection due to group C nontyphoid salmonellae

From January 2000 through September 2004, a total of 54 patients with infection due to group C nontyphoid salmonellae were evaluated; 8 patients had gastroenteritis alone, and 46 patients had bacteremia. Of the 46 patients who had bacteremia, 12 had endovascular infection and 34 did not. The number of infections due to ciprofloxacin-resistant Salmonella organisms is increasing. Ciprofloxacin-resistant Salmonella organisms predisposed patients to acquire bacteremia, but they did not seem to predispose patients to acquire endovascular infection.

Infectious Aortitis

Infection of the aorta usually results from septic embolization to the vasa vasorum, hematogenous seeding of an existing aneurysm, or extension from a contiguous site of infection. The diagnosis should be considered in patients, often men over the age of 50 years with atherosclerosis, who present with fever, abdominal pain, palpable abdominal mass, and leukocytosis, with or without positive blood cultures. In the pre-antibiotic area, infectious aortitis was largely a complication of infective endocarditis, and was usually caused by group A streptococci, Streptococcus pneumoniae, or Haemophilus influenzae. Now a diverse array of bacteria and fungi has been associated, most commonly Salmonella species, which comprise nearly one third of the abdominal aortic infections and Staphylococcus aureus. Computed tomography is the most useful imaging modality. Medical treatment alone carries a high mortality, whereas the mortality with surgery combined with antimicrobial treatment is lower. Empiric antibiotics effective against S. aureus and gram-negative rods, such as Salmonella, should be initiated in cases identified before microbiologic diagnosis. Surgical debridement and revascularization should be completed early because delay may lead to aneurysm rupture, which increases mortality. The intent of surgery is to 1) control hemorrhage, if the aneurysm has ruptured; 2) confirm the diagnosis; 3) control sepsis; and 4) reconstruct the arterial vasculature. The patient should remain on parenteral or oral antibiotics for at least 6 weeks, perhaps longer, to assure full eradication of the pathogen and prevent recurrent infection. Close medical follow-up is indicated and includes serial blood cultures and computed tomography scans.