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

Abscess and aneurysm: A case of tuberculous abscess causing an aortic pseudo-aneurysm

Thoracic aortic pseudoaneurysms are a rare but serious complication of infectious processes, often resulting from mycotic (infectious) aneurysms, occurring when the vessel wall is compromised by an infection, leading to the formation of a pseudoaneurysm [1]. Mycotic aneurysms typically result from bacteremia or fungemia, with common sources being infective endocarditis or other systemic infections. Tuberculosis, though a common infectious disease worldwide, is an unusual cause of aortic pseudoaneurysm formation. We present the case of a 26-year-old Asian male with a history of positive Quantiferon test, who presented with two weeks of back pain, hemoptysis, cough, night sweats, fever, and chills. CT imaging revealed a pseudoaneurysm at the T11-T12 level, associated with an epidural abscess, prevertebral rim-enhancing collection, and signs of osteomyelitis. The patient underwent endovascular repair of the aortic aneurysm, followed by drainage and biopsy of the epidural abscess and antibiotic therapy for the underlying infection. This case demonstrates the rare occurrence of a mycotic aneurysm caused by tuberculous infection, and the importance of early diagnosis and prompt surgical intervention to prevent catastrophic complications such as rupture, sepsis, or neurological impairment.

A Fatal Abdominal Aortic Mycotic Aneurysm in a Child With Concurrent Pericarditis

Mycotic aneurysms, also called infected aneurysms, are localized irreversible vascular dilations caused by arterial wall infection with subsequent vessel wall weakening. They are rare but potentially life-threatening conditions that can occur from bacterial seeding into an intact vascular wall or superinfection of a pre-existing aneurysm or atherosclerotic plaques. Risk factors in children include coarctation of the aorta, in-dwelling arterial catheters, postcardiac surgery, or immunosuppressive states. We report a rare case of an abdominal aortic mycotic aneurysm in a four-year-old patient with concurrent pericarditis. Her nonspecific presentation with fever and body pains posed a diagnostic and therapeutic challenge. We discuss the risk factors, diagnosis, and management of this condition.

Mycotic aneurysms: uncommon pathogens and treatment conundrums

Introduction. Mycotic aneurysms, characterized by vessel wall dilation resulting from infections including bacteria, fungi, and viruses, are a rare but severe consequence of systemic infections. The term 'mycotic' was coined by William Osler to describe the first instance of a fungal-induced infected aneurysm. These aneurysms, accounting for 0.6% of aneurysms in Western countries, carry a higher risk of rupture compared to uninfected aneurysms. While the femoral artery, aorta, and intracranial arteries are commonly affected, pathogens causing mycotic aneurysms vary across regions. Diagnostic challenges arise from nonspecific symptoms such as fever, and discomfort. To prevent the substantial morbidity and mortality associated with mycotic aneurysms, timely identification and treatment are paramount. We present a case series highlighting mycotic aneurysms caused by some rare pathogens - Salmonella Paratyphi A, Streptococcus pneumoniae, and Pseudomonas aeruginosa. Methods. This case series involves three patients diagnosed with mycotic aneurysms due to unusual pathogens. We describe each patient's clinical presentation, medical history, physical examination findings, laboratory results, imaging studies, and the diagnostic process leading to the identification of the causative pathogens. Results. The first patient is a 70-year-old gentleman who presented with a ruptured infra-renal abdominal aortic pseudoaneurysm caused by Salmonella Paratyphi A. The second patient is a 66-year-old gentleman with a Streptococcus pneumoniae-associated descending thoracic aortic pseudoaneurysm. The third patient is a 70-year-old gentleman with a ruptured descending thoracic aortic aneurysm with an occult aorto-oesophageal fistula due to Pseudomonas aeruginosa infection. The description highlights unique clinical features, laboratory findings, imaging results, and the management approaches undertaken in each patient. Conclusion. Mycotic aneurysms, pose diagnostic challenges due to their nonspecific symptoms. Early identification and intervention are essential to mitigate the severe complications associated with these aneurysms. The presented cases underscore the need for a comprehensive approach to diagnosis and management, ensuring optimal outcomes for patients affected by mycotic aneurysms.

Lumbar vertebral diskitis-osteomyelitis with mycotic abdominal aortic aneurysm caused by Streptococcus mitis

Vertebral osteomyelitis is a well-documented disease entity in literature with various known etiologies. However, vertebral diskitis-osteomyelitis secondary to an infected aortic aneurysm is an uncommon and life-threatening complication. We present the case of a 65-year-old male patient who presented with chronic low back pain that acutely worsened for 1 to 1.5 months and was diagnosed with vertebral diskitis-osteomyelitis secondary to a contiguous infection from an adjacent mycotic aortic aneurysm. To our knowledge, this is one of the few cases reported of vertebral diskitis-osteomyelitis secondary to mycotic aortic aneurysm. We discuss the findings on CT and MRI, as well as the value of imaging in guiding management.

Cardiac Tuberculosis: A Case Series from Ethiopia, Italy, and Uganda and a Literature Review

Extrapulmonary tuberculosis (TB) is estimated to account for up to 20% of active cases of TB disease, but its prevalence is difficult to ascertain because of the difficulty of diagnosis. Involvement of the heart is uncommon, with constrictive pericarditis being the most common cardiac manifestation. Diagnostic research for cardiac disease is frequently lacking, resulting in a high mortality rate. In addition to direct cardiac involvement, instances of cardiac events during antitubercular therapy are described. This case series describes five cases of TB affecting the heart (cardiac TB) from Italy and high-burden, low-income countries (Ethiopia and Uganda), including a case of Loeffler syndrome manifesting as myocarditis in a patient receiving antitubercular therapy. Our study emphasizes how cardiac TB, rare but important in high-burden areas, is a leading cause of pericardial effusion or pericarditis. Timely diagnosis and a comprehensive approach, including imaging and microbiological tools, are crucial. Implementing high-sensitivity methods and investigating alternative samples, such as detection of tuberculosis lipoarabinomannan or use of the GeneXpert assay with stool, is recommended in TB control programs.

Rapid formation of aortoesophageal fistula complicated by mycotic thoracic aortic aneurysm secondary to infective endocarditis

A 73-year-old man was admitted with four weeks of intermittent fever. He had a history of total aortic arch replacement for aortic arch aneurysm four years prior. CT scans showed no abnormalities before admission. Repeated blood cultures yielded Streptococcus anginosus and Prevotella melaninogenica, suggesting infective endocarditis (IE). Transesophageal echocardiography revealed a vegetation on the aortic valve, confirming IE. He suddenly presented with massive hematemesis and hypotension. Endoscopy revealed an elevated lesion with a laceration but no active bleeding in the esophagus. CT scans showed a thoracic aneurysm involving the esophagus. A diagnosis of aortoesophageal fistula (AEF) complicated by mycotic thoracic aortic aneurysm (MTAA) was made, and he underwent stent graft interpolation followed by minimally invasive esophagectomy. MTAAs are more prone to rupture than arteriosclerotic aneurysms as they are usually not true but pseudoaneurysms. Antecedent infection, including endocarditis, sepsis, predisposes to MTAA. AEF is a rare but life-threatening cause of gastrointestinal bleeding characterized by Chiari's triad. There have been no reports of such rapid formation of AEF after the graft replacement, as shown here. A recent article reported a rapid formation (16 days) of AEF after thoracic endovascular aortic repair, emphasizing prosthetic infection as the most important risk factor. Our case underscores the importance of suspecting AEF and conducting repeated appropriate examinations even if initial examinations do not reveal any aneurysms.

Mycotic Aortic Aneurysm Secondary to Salmonella enterica Infection: A Case Report and Treatment Approach

Mycotic (infected) aortic aneurysm is a severe clinical condition with high morbidity and mortality. Salmonella spp. is a Gram-negative, rod-shaped bacteria that is typically limited to the gastrointestinal tract and resolves spontaneously but can progress to invasive infections such as bacteremia. Serious complications may arise, particularly in debilitated, elderly, and neonatal patients. We describe the case of a 74-year-old female with a history of diabetes and hypertension who presented with shortness of breath, fever, chills, abdominal pain, vomiting, and diarrhea. The patient's blood culture tested positive for Salmonella enterica, and she was given ceftriaxone based on the results, but he remained symptomatic. A computed tomography scan of the chest with contrast revealed a mycotic aneurysm of the thoracic aorta. The patient was urgently transferred to a higher level of care and underwent emergency thoracic endovascular aortic repair with stenting and intravenous antibiotics. The presence of an infected aneurysm and associated abscess formation in such high-risk patients makes the endovascular approach more suitable than other options such as open surgery, aneurysmal excision and ligation without arterial reconstruction, excision with immediate reconstruction, and excision with interval reconstruction.

Rupture of Non-aneurysmal Mycotic Thoracic Aortic Arteritis Caused by Campylobacter fetus

Campylobacter fetus (C. fetus) demonstrates a preference for vascular tissue and is an infrequent etiology of mycotic aortic arteritis (MAA), mostly occurring in the abdominal aorta. MAA characteristically has a rapid progression to aneurysm formation and subsequently, to aortic rupture. We present a 73-year-old woman with non-aneurysmal mycotic thoracic aortic arteritis (MTAA) complicated with a rupture caused by C. fetus. She presented after four days of pain in the lower abdomen. Contrast-enhanced computed tomography revealed non-aneurysmal descending thoracic aorta arteritis and an abdominal aorta aneurysm, and the blood cultures were positive for C. fetus. Antibiotic therapy relieved the abdominal pain. However, eight days after the antibiotic therapy, she died because of a rupture of the non-aneurysmal MTAA. The non-aneurysmal MTAA caused by C. fetus ruptured while the infection was being treated with appropriate antibiotics, and there was no sign of arterial dilatation. An early open or endovascular repair after a short pre-operative antibiotic therapy may be required for non-aneurysmal MAA caused by C. fetus. More cases of non-aneurysmal MAA caused by C. fetus are needed to determine the clinical course and to decide the treatment strategy.

A rare case of mycotic aortic aneurysm with Clostridium perfringens culture

Key Clinical Message

As only early diagnosis, prompt surgical intervention, and appropriate antibiotic therapy can decrease clostridial MAA mortality rate; keeping in mind a broad differential diagnosis in a patient with sepsis and unusual vascular symptoms is important.

Abstract

Mycotic aortic aneurysm (MAA) is an infrequent but very consequential condition characterized by the pathological disruption of the aorta due to infection. Clostridium perfringens is a bacterium that falls under the taxonomic classification of the genus Clostridium. Although mycotic aneurysm is often not commonly linked with this infection, there are instances when it may function as a causative agent for MAA. Timely diagnosis and thorough therapeutic techniques, including surgical intervention and quick administration of appropriate antibiotics, can potentially reduce the mortality rate associated with clostridial MAA. In this study, we presented a clinical report detailing the diagnosis of a mycotic aneurysm caused by C. perfringens in the thoracic aorta in a 66-year-old male patient with a history of diabetes mellitus and a recent prostate biopsy. Furthermore, we discussed the surgical approach and overall management strategy to address this case.

A Rare Case of Mycotic Aneurysm Due to Methicillin-Sensitive Staphylococcus aureus (MSSA) Bacteremia

Mycotic aneurysm is defined as an infection of the arterial wall either by fungi or bacteria. Although, a rare complication of infection, it is associated with high morbidity and mortality. We describe a 69-year-old female with a rare thoracic aortic mycotic aneurysm, with no clear source of infection and a predominantly atypical presentation, manifesting primarily as heart failure, at a rural community hospital. Our case also depicts the rapid development of aortitis and mycotic aneurysms. This case highlights the challenges in the diagnosis and management of this condition.