Infectious Aortitis

Abstract

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.

Aortitis

“…A number of organisms have been associated with infectious aortitis, most commonly the Salmonella and Staphylococcal species, along with Streptococcus pneumonia. 1,2 In most cases of bacterial aortitis, a segment of the aortic wall with preexisting pathology such as an atherosclerotic plaque or aneurysm sac is seeded by bacteria via the vasa vasorum. 1,2 Tuberculous aortitis, an uncommon problem in the developed world, may occur as a result of direct seeding of the thoracic aorta from adjacent infected tissues such as infected lymph nodes or lung lesions or by miliary spread.…”

“…1,2 In most cases of bacterial aortitis, a segment of the aortic wall with preexisting pathology such as an atherosclerotic plaque or aneurysm sac is seeded by bacteria via the vasa vasorum. 1,2 Tuberculous aortitis, an uncommon problem in the developed world, may occur as a result of direct seeding of the thoracic aorta from adjacent infected tissues such as infected lymph nodes or lung lesions or by miliary spread. 2 Syphilitic or luetic aortitis, now exceedingly rare, typically involves the ascending aorta and is associated with thoracic aortic aneurysm.…”

Bartonella quintana Aortitis in a Man with AIDS, Diagnosed by Needle Biopsy and 16S rRNA Gene Amplification

“…One case report described B. quintana in a patient with AIDS manifesting as a single, large intra-abdominal BA lesion which eroded into the mesenteric vasculature (10). CD4 ϩ T cell counts were in the very low range at which BA occurs (9) for both the latter patient (10 cells/mm 3 ) and our patient (68 cells/mm 3 ). Bartonella infections can be diagnosed (8) by histopathological examination of tissue with Warthin-Starry silver stain, by special Bartonella blood culture analysis (9) (unavailable in most hospital laboratories), by serological assays, and increasingly, by PCR amplification of DNA extracted from biopsy tissue, using specific or There are no prospective studies of Bartonella treatment in immunocompromised hosts.…”

“…and rifabutin (150 mg p.o. daily) treatment for an additional 6 months and then on doxycycline treatment alone until his CD4 ϩ T cell count remained consistently above 200 cells/mm 3 (approximately 14 months after the initial diagnosis of Bartonella aortitis) (Table 1) (1). Eighteen months after the diagnosis, his B. quintana IgG level was Ͻ1:64 and his B. henselae IgG level was 1:128 (Table 1).…”

Infectious Thoracic Aortitis: A Literature Review

“…19 Factors apparently linked to a worse prognosis are advanced age, diagnosis delay, gram-negative bacilli infection, immunodepression, thoracic location, medical treatment alone, and complication occurrence (such as rupture, embolization, or septic shock). 1,14,19 Some authors recommend close medical follow-up that includes serial blood cultures and CT scans, 12 while others do not perform such approaches, recommending only clinical surveillance. 16 …”