Antimicrobial drug resistance in salmonella-infected aortic aneurysms

Yersinia enterocolitica Bacteremia Associated with a Ruptured Abdominal Aortic Aneurysm: A Case Report with Literature Review

Yersinia enterocolitica is a foodborne pathogen, mainly associated with disorders involving the gastrointestinal tract, including diarrhea, ileitis, and mesenteric lymphadenitis. Extraintestinal presentation is uncommon in healthy individuals, but bacteremia is reported in immunocompromised hosts. We present a 74-year-old male with Y. enterocolitica serogroup O:3 bacteremia who complicated to rupture of an abdominal aortic aneurysm. With the current case report, we aimed to emphasize the association of Y. enterocolitica bacteremia with abdominal aortic aneurysm rupture. Better surveillance is needed, not only to reduce morbidity and mortality but also to update current epidemiological data on the incidence of such associations.

Successful Endovascular Repair of Infectious External Iliac Artery Anastomotic Pseudoaneurysm With Graft Preservation Post-Kidney Transplantation: Case Report and Review of Literature

BACKGROUND

Allograft artery-infected pseudoaneurysm (PA) represents a rare but life-threatening complication of kidney transplantation (KT). A review of the literature, showed that nearly all these cases ended resulted in graft loss. We presented a case of post-KT-infected external iliac artery anastomotic PA successfully managed by endovascular stenting with graft preservation. Additionally, we reviewed the pertinent literature.

METHOD

In this article, we described a hypertensive, 47-year-old man who presented 1 month post-cadaveric KT with acute kidney injury and gram-negative bacteremia secondary to a large infectious anastomotic PA of the external iliac artery.

RESULTS

Because of favorable anatomy, successful arterial angio-stent fixation of the main renal artery PA, sparing the lower polar artery, was performed after 1 week of antibiotic and fungal coverage.

CONCLUSION

Patient was discharged after 2 weeks with functioning graft. Graft function was stable after 3 months.

Mycotic Thoracic Aortic Aneurysm: Epidemiology, Pathophysiology, Diagnosis, and Management

Mycotic thoracic aortic aneurysm (MTAA) is an aneurysm of the aorta caused by infection of the vessel tissue through microbial inoculation of the diseased aortic endothelium. It is most commonly caused by bacteria. Rarely, it can be caused by fungi. However, viral aortic aneurysm has never been reported. Depending on the area and time period investigated, the infections organism discovered may vary significantly. Little is known about the natural history of MTAA due to its rarity. It is not known if they follow the same pattern as other TAAs. However, it is unclear whether MTAA follows a similar clinical course. The combination of clinical presentation, laboratory results, and radiographic results are used to make the diagnosis of MTAA. Treatment of MTAA is complex since patients frequently present at a late stage, frequently with fulminant sepsis, as well as concomitant complications such as aneurysm rupture. While medical treatment, including antibiotics, is recommended, surgery is still the mainstay of management. Surgery to treat MTAA is complicated and carries a high risk of morbidity and mortality and includes both open repairs and endovascular ones. In this review, we explore the etiology, pathogenesis, clinical presentations, diagnostic modalities as well as treatment management available for MTAA.

Mycotic (Infected) Pseudoaneurysm, a Diagnostic Challenge - Case Series

Mycotic pseudoaneurysm (or infected pseudoaneurysm) is an infectious arteritis, leading to the destruction of the arterial wall with the formation of a blind, saccular outpouching contiguous with the arterial lumen. Delayed management or non-management of mycotic pseudoaneurysms is associated with high morbidity and mortality due to complications such as arterial rupture, hemorrhage, and fulminant sepsis. Earlier diagnosis of mycotic pseudoaneurysm is essential for time management. Multidetector computed tomography (MDCT) is a widely used imaging modality for detecting the mycotic pseudoaneurysm, its characterization, and vascular mapping. MDCT findings of mycotic pseudoaneurysm are blind, saccular outpouching of an artery with irregular arterial wall, perivascular soft-tissue mass, or edema. Uncommon results of MDCT include arterial lumen thrombosis, arterial wall calcification, and perivascular gas. Management of mycotic pseudoaneurysm includes endovascular stenting with graft repair, endovascular embolization, open surgery, medical therapy (intravenous antibiotics), or a combination of these. We report three cases of mycotic pseudoaneurysm affecting aortic isthmus, a segmental branch of the pulmonary artery, and the internal mammary artery. All cases posed a diagnostic challenge, which only on subsequent imaging revealed to be a mycotic pseudoaneurysm.

Mycotic pseudoaneurysm of the aortic isthmus secondary to salmonella infection causing a diagnostic dilemma

Mycotic pseudoaneurysms usually arise from an infectious arteritis or mycotic aneurysms secondary to weakening and destruction of the arterial wall resulting in a contained rupture. We report a case of a mycotic pseudoaneurysm affecting the aortic isthmus of the thoracic aorta which is an extremely rare infection. To our knowledge no case report of mycotic pseudoaneurysm of the aortic isthmus secondary to salmonella infection has thus far been described. The specific case we present is also unique in that it posed a diagnostic imaging dilemma where the initial imaging revealed a periaortic mass which could not be accurately characterized and only on subsequent imaging reveal itself to be a thrombosed mycotic pseudoaneurysm. We hope that our case report highlights to the medical community the high degree of suspicion one should have regarding pseudoaneurysms when dealing with a complex mass intimately related to a vascular structure.

Mycotic aneurysm due to Salmonella species: clinical experiences and review of the literature

The mortality of patients with mycotic aneurysms is high, especially in East Asia, and infection by Salmonella species is the most common. Our study aimed to improve prognosis of adult mycotic aneurysms with early diagnosis and accurate treatment. Four adult patients with mycotic aneurysm caused by Salmonella were included and analyzed by single-center retrospective analysis. Cases reported in the literature during the past 10 years were also summarized. The average age of the 4 male patients was 61.25 years, while that of the 53 cases reported in the literature was 65.13 years. Hypertension, diabetes, and atherosclerosis were common complications. Most patients presented fever and experienced pain at the corresponding position of the aneurysm. Laboratory examination found an increased number of white blood cells accompanied by an increase in inflammatory markers. Most aneurysms were found in the abdominal aorta, while the rupture of an aneurysm was the most common complication. The mortality rates were 21.43 and 7.14% after open surgery or endovascular aneurysm repair (EVAR) intervention, respectively. The recurrence rates of infection were 0 and 17.85% for both treatments, respectively. The mortality rate of mycotic aneurysm caused by Salmonella infection was high in middle-aged males with hypertension, diabetes, and atherosclerosis. The possibility of a Salmonella-infected aneurysm should be considered in these high-risk groups presenting chills, fever, chest, and back pain. Open surgery was superior to EVAR treatment in the clearance of infected foci and the reduction of postoperative recurrence. The recurrence of postoperative infection can be prevented by intravenous antibiotic therapy for 6 weeks post-surgery.

Primary Infected Aortic Aneurysm: Clinical Presentation, Pathogen, and Outcome

PURPOSE

Infected aneurysm of the aorta and adjacent arteries is rarely occurring and can be fatal without surgical intervention. Within the medical community, the most efficacious treatment strategy to address infected aortic aneurysm remains controversial. In this study, we have reviewed our treatment experience with 109 patients.

METHODS

We included in our study all consecutive patients treated for primary infected aortic aneurysm at our facility between 1995 and 2011. Aneurysm-related mortality was defined as the presence of in-hospital and late mortality related to infection or postoperative complications.

RESULTS

The median patient age was 72 years (range, 35-88), and 87 (80%) were male. Pathogen was isolated in 101 patients, and the most common microorganism identified was non-typhoid Salmonella in 61 (60%), followed by Staphylococcus aureus in 16 (16%) and Streptococci species in 7 (7%). Eighty-five (78%) patients underwent surgical treatment. Surgery included open repair with in-situ graft replacement in 77 (71%) and endovascular repair in 8 (7%). The aneurysm-related mortality rate was 67% in medically treated and 21% in surgically treated patients, with a median follow-up duration of 31.5 months (range 1-189). Additionally, risk factors for aneurysm-related mortality included old age, chronic lung disease, psoas muscle abscess, short duration of preoperative antibiotics, no operation, and probably endovascular repair.

CONCLUSIONS

Non-typhoid Salmonella was the most common pathogen found in our study group patients with infected aortic aneurysm. It appears that prolonged preoperative antibiotic treatment followed by open in-situ graft replacement remains the preferred and most effective treatment strategy.

KEY WORDS

Infected aortic aneurysm; Outcome; Pathogen; Surgery.

Clinical, microbiologic, and outcome analysis of mycotic aortic aneurysm: the role of endovascular repair

BACKGROUND

Mycotic aortic aneurysm (MAA) is an infrequent but devastating form of vascular disease.

METHODS

We conducted a retrospective cohort study at a major medical center to identify independent risk factors for MAA and to provide opinions about treating it. The study population consisted of 43 patients who had had 44 MAAs over a period of 15 y.

RESULTS

All of the patients had positive blood cultures, radiologic findings typical of MAA, and clinical signs of infection (leukocytosis, fever, and elevated C-reactive protein). The mean age of the patients was 63.8±10.6 y and the mean period of their follow up was 35.7±39.3 mo. Twenty-nine patients with MAAs underwent traditional open surgery, 11 others received endovascular stent grafts, and four MAAs were managed conservatively. The most frequent causative pathogens were Salmonella (36/44 patients [81.8%]), in whom organisms of Salmonella serogroup C (consisting mainly of S. choleraesuis) were identified in 14 patients, organisms of Salmonella serogroup D were identified in 13 patients, and species without serogroup information were identified in nine patients. The overall mortality in the study population was 43.2% (with an aneurysm-related mortality of 18.2%, surgically related mortality of 13.6%, and in-hospital mortality of 22.7%).

CONCLUSIONS

Shock is a risk factor for operative mortality. Misdiagnosis and treatment of MAA as low back pain, co-existing connective-tissue disease such as systemic lupus erythematosus and rheumatoid arthritis, and Salmonella serogroup C-associated bacteremia are risk factors for aneurysm-related death. Endovascular repair should be considered as an alternative option to the open repair of MAA.

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.

Non-typhoidal Salmonella infections in pigs: a closer look at epidemiology, pathogenesis and control

Contaminated pork is an important source of Salmonella infections in humans. The increasing multiple antimicrobial resistance associated with pork-related serotypes such as Salmonella Typhimurium and Salmonella Derby may become a serious human health hazard in the near future. Governments try to anticipate the issue of non-typhoidal Salmonella infections in pork by starting monitoring programmes and coordinating control measures worldwide. A thorough knowledge of how these serotypes interact with the porcine host should form the basis for the development and optimisation of these monitoring and control programmes. During recent years, many researchers have focussed on different aspects of the pathogenesis of non-typhoidal Salmonella infections in pigs. The present manuscript reviews the importance of pigs and pork as a source for salmonellosis in humans and discusses commonly accepted and recent insights in the pathogenesis of non-typhoidal Salmonella infections in pigs, with emphasis on Salmonella Typhimurium, and to relate this knowledge to possible control measures.

Type B aortic dissection associated with Salmonella infection

A 59-year-old man with a long history of hypertension and diabetes was admitted to our hospital with acute type B aortic dissection 14 days after the sudden onset of back pain. The dissecting descending thoracic aorta was enlarged to 5.2 cm in diameter, and laboratory tests showed an elevated white blood cell count (15530/mm3) and an increased C-reactive protein level (19.2 mg/dl). Computed tomography performed 2 days after admission revealed rapid growth of the aortic dissection. Blood cultures obtained upon admission were positive for Salmonella. Impending rupture of the aortic dissection complicated by Salmonella infection was strongly suspected, and the patient underwent emergency surgery consisting of debridement and prosthetic graft placement covered by an omental flap. In this case, it is believed that insidious Salmonella aortitis caused acute type B aortic dissection.