From the Guidelines
Infectious aortitis is a rare but serious infection of the aorta that requires prompt diagnosis and treatment with immediate hospitalization, blood cultures, and empiric broad-spectrum antibiotics, such as vancomycin 15-20 mg/kg IV every 12 hours plus ceftriaxone 2g IV daily, while awaiting culture results. The diagnosis of infectious aortitis involves imaging with CT angiography or MRI to show aortic wall thickening, periaortic inflammation, or aneurysm formation 1. Treatment typically requires 6 weeks of targeted antibiotic therapy based on culture results, often with surgical intervention for complications like aneurysms or persistent infection. Common causative organisms include Staphylococcus, Streptococcus, Salmonella species, and fungi in immunocompromised patients, as reported in the 2010 ACCF/AHA/AATS/ACR/ASA/SCA/SCAI/SIR/STS/SVM guidelines for the diagnosis and management of patients with thoracic aortic disease 1.
Key Considerations
- The condition develops through direct invasion from adjacent infections, hematogenous spread, or as a complication of endocarditis 1.
- Without proper treatment, infectious aortitis can lead to life-threatening complications including aortic rupture, septic emboli, or persistent bacteremia.
- Close monitoring with serial imaging and inflammatory markers is necessary throughout treatment, and surgical consultation should be obtained early in the disease course to evaluate the need for intervention.
- In situ reconstruction in patients with extensive perigraft infection, lifelong suppressive therapy, and excision of the infected aortic graft to minimize ischemia may be necessary, as suggested by the 2016 American Heart Association scientific statement on vascular graft infections, mycotic aneurysms, and endovascular infections 1.
Treatment Approach
- Empiric broad-spectrum antibiotics should be started immediately, with vancomycin 15-20 mg/kg IV every 12 hours plus ceftriaxone 2g IV daily being a suitable option.
- Targeted antibiotic therapy should be adjusted based on culture results, with a typical duration of 6 weeks.
- Surgical intervention may be necessary for complications like aneurysms or persistent infection, with a 2-stage procedure considered only in patients who are stable hemodynamically 1.
From the Research
Diagnosis of Infectious Aortitis
- The diagnosis of infectious aortitis 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 2.
- Computed tomography is the most useful imaging modality for diagnosing infectious aortitis 2, 3.
- Establishing a diagnosis of aortic infection before the formation of an aneurysm or rupture is very difficult, but essential in preventing the devastating complications 3.
Treatment of Infectious Aortitis
- Medical treatment alone carries a high mortality, whereas the mortality with surgery combined with antimicrobial treatment is lower 2.
- Empiric antibiotics effective against S. aureus and gram-negative rods, such as Salmonella, should be initiated in cases identified before microbiologic diagnosis 2.
- Surgical debridement and revascularization should be completed early because delay may lead to aneurysm rupture, which increases mortality 2.
- 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 2.
- Endovascular interventions have improved the prognosis of patients with aortitis complications, and can be used as a therapeutic approach 4.
Clinical Presentation and Risk Factors
- Clinical presentation of infectious aortitis is variable, and a high index of suspicion is required for timely diagnosis and management 5.
- Infectious aortitis is more common among older patients with preexisting pathology, such as atherosclerosis 2, 5, 6.
- Risk factors for atherosclerosis, such as hypertension, are common in patients with infectious aortitis 6.
- Sudden unexpected death can occur in patients with infectious aortitis, even in the recovery phase of antecedent infection 6.