CASE 13169 Published on 06.12.2015

Syphilitic aortitis

Section

Cardiovascular

Case Type

Clinical Cases

Authors

Antunes, N.; Serrado, M. ; Santos, R. ; Fernandes, O.; Figueiredo, L.

Hospital Santa Marta,Centro Hospitalar Lisboa Central,Departamento Radiologia; Rua Santa Marta 1050 Lisboa, Portugal; Email:nhantunes@hotmail.com
Patient

62 years, male

Categories
Area of Interest Cardiovascular system ; Imaging Technique CT, Image manipulation / Reconstruction
Clinical History
A 62 year-old man with hypertension and dyslipidemia was referred due to an alteration on his chest x-ray that motivated the request for a chest-CT. The patient was asymptomatic but mentioned a history of syphilis years ago, apparently untreated.
Imaging Findings
Thoracic CT without intravenous contrast showed irregularity of the aortic walls and a distal ascending aortic aneurysm (axial diameters of 61 x 59 mm) and proximal descending aortic aneurysm (axial diameters of 70 x 67 mm). The posterior wall of the proximal descending aorta exhibits a low attenuation crescent-shaped area, corresponding to a mural thrombus (differentiating it from an intramural hematoma, which would be hyperattenuating).
Contrast-enhanced CT further displays the irregularity of the intima, but shows no signs of an intimal flap (suggestive of aortic dissection with a thrombosed false lumen).
There is marked thickening of the aortic wall with soft-tissue accumulation, owing to the chronic inflammatory process, that leads to wrinkling of the intima and diffuse fibrosis.
These events ultimately weaken the vascular wall, leading to the formation of aneurysms, as clearly depicted on the CT MIP.
Discussion
A. Aortitis, or inflammation of the aortic wall, can present various aetiologies, each with a different clinical history, morphology, therapeutic options and prognosis.
B. It can be classified as infectious or noninfectious. In developed countries, aortic aneurysms due to infectious causes have declined significantly. Autoimmune disease (Giant Cell Arteritis, Takayasu or Behçet disease) now represent the majority of cases [2].
C. The aneurysms associated with “microbial arteritis” are known as «Mycotic aneurisms», and in the past were usually caused by bacterial endocarditis or syphilis [3].
D. There is an increased risk of infectious aortitis with some predisposing conditions (immunosuppression, diabetes, atherosclerotic disease, previous heart or aortic surgery). The infectious agents include E. coli, Treponema pallidum, Salmonella or M. tuberculosis [1].
E. Syphilitic aortitis, caused by Treponema pallidum, typically occurs 10-30 years after the primoinfection (tertiary syphilis), and usually involves the ascending aorta (60%) and the aortic arch (30%).
F. The radiologic appearance of syphilitic aortitis results from an obliterative endarteritis of the vasa vasorum, [1] which gradually leads to replacement of the elastic and muscle fibres for fibrosis. This process progressively weakens the aortic wall and causes retraction of the media and wrinkling of the intima, leading to a ‘tree-bark appearance’. This reflects on the macroscopic appearance of the aorta, with multiple irregularities owing to the scattered focus of fibrosis.
G. The natural history of the disease ultimately progresses to aneurysm formation [4], most frequently saccular aneurysm, due to gradual weakening of the wall [1]. This inflammatory process may also involve the aortic valve - causing valvular regurgitation - or the coronary arteries.
H. Diagnosis relies on serologic testing and the treatment options include open reparative surgery and antibiotic therapy (Penicillin) [2]. The patient tested positive for TPHA (treponemal pallidum particle agglutination) and for VDRL (venereal disease research laboratory) test on blood (titre 1/32). He was submitted to open reparative surgery and the histological analysis of the surgical piece revealed findings compatible with atherosclerosis and lymphoplasmocitary infiltrate suggestive of syphilis.
Differential Diagnosis List
Syphilitic aortitis.
Mycotic aneurysm due to infective endocarditis or other infectious causes
Infectious aortitis
Atherosclerotic aortic disease
Final Diagnosis
Syphilitic aortitis.
Case information
URL: https://www.eurorad.org/case/13169
DOI: 10.1594/EURORAD/CASE.13169
ISSN: 1563-4086
License