Aortitis



Aortitis


Joseph J. Maleszewski, M.D.

Allen P. Burke, M.D.



Noninfectious Aortitis


Overview and Classification

Aortitis is broadly defined as inflammation of the aortic wall. Conditions that result in secondary inflammation are not typically considered aortitis. Aortic atherosclerosis, a disease that primarily affects the endothelium, is also typically not considered a form of aortitis, despite what is sometimes a considerable inflammatory component to the process.

Noninfectious aortitis is classified into several major disease classifications: giant cell/granulomatous aortitis (including Takayasu aortitis), lymphoplasmacytic aortitis (including IgG4-related sclerosing disease and that associated with rheumatologic disease), and more unusual aortic involvement by entities such as granulomatosis with polyangiitis (GPA; formerly known as Wegener granulomatosis), sarcoidosis, and Behçet disease1,2,3 (Table 189.1). This chapter focuses on the more entities more commonly encountered by the surgical or autopsy pathologist.

In addition to the aforementioned traditional disease-specific classification of aortitis, a histologic pattern-based classification system has been recently proposed for use by pathologists.4 Categories such as granulomatous/giant cell pattern-aortitis, lymphoplasmacytic pattern, mixed inflammatory pattern, suppurative pattern, and unclassified may be particularly helpful when limited clinical information is available.








TABLE 189.1 Aortitis: Clinical and Pathologic Findings

Clinical

Site in Aorta and Other Sites of Involvement

Histologic Findings


Noninfectious


Granulomatous (giant cell)

Association with polymyalgia rheumatica and temporal arteritis, always aneurysmal, often with aortic insufficiency, aortic dissection may occur female predilection; usually >60 y

Ascending aorta

Block-like zonal necrosis, media, with granulomatous giant cell reaction at the rim; intimal and adventitial fibrosis


Diffuse, lymphoplasmacytic, nonnecrotizing (less common)


Takayasu

Hypertension, symptoms of vascular occlusion; young women, Asian descent aneurysms or stenoses

Ascending aneurysms, abdominal constriction; narrowing of coronary ostia, arch vessels, and mesenteric arteries

Similar to isolated with marked adventitial fibrosis and intimal fibrosis; zonal/laminar necrosis may not be as discrete


Lymphoplasmacytic

Rheumatoid arthritis, giant cell arteritis, others; slight female predilection, generally younger patientsa; usually aneurysmal

Ascending aorta


Descending thoracic (unusual)

Same as isolated; nonnecrotizing type may be more frequent; may have elevated IgG4-reactive plasma cell infiltrate


Infectious


Syphilitic

Currently rare; occurs 10-15 y after untreated syphilis

Ascending, descending thoracic, massive aneurysms with erosion into surrounding structures

Necrotizing aortitis, prominent adventitial inflammation and scarring, similar features as isolated aortitis, possibly less discrete areas of necrosis


Purulent (mycotic)

History of bacteremia or osteomyelitis

Descending thoracic, mesenteric arteries, femoral arteries

Purulent inflammation with or without rupture and pseudoaneurysm


a Inflammatory aortic disease has been reported in patients with sarcoidosis, Behçet disease, rheumatoid arthritis, ankylosing spondylitis, lupus, and other autoimmune diseases. The link between the systemic rheumatologic disease and the aortic aneurysm is not always clear.



Clinical Features

Most noninfectious forms of aortitis come to clinical attention because of ascending aortic dilatation/aneurysm formation and/or symptoms of secondary aortic valve regurgitation. Six to ten percent of surgical specimens for ascending aortic aneurysms demonstrate aortitis histologically. A small subset of individuals will experience aortic dissection or rupture, in which case sudden death may be the initial manifestation.

The etiology of noninfectious aortitis is unclear, but many instances are believed to be related to autoimmune phenomena and ˜39% of cases are associated with frank autoimmune disorders (range from 13% to 84%).2,5,6,7,8,9,10


Gross Features

The gross features of noninfectious aortitis are similar across all of the histologic subtypes.11 Aortitis can affect any site in the aorta, but has a predilection for the ascending aorta, which usually manifests the disease by increased diameter, dissection, and/or rupture.

Intimal wrinkling (“tree-barking”) similar to infectious aortitis (Fig. 189.1). In many cases (particularly Takayasu aortitis), there is thickening of the aortic wall. Occasionally, there is minimal dilatation and even aortic narrowing (which may also be a curious feature of Takayasu aortitis) (Figs. 189.2 and 189.3).







FIGURE 189.1 ▲ Ascending aortic aneurysm, aortitis. The specimen is a circumferential ring that is opened revealing marked dilatation of the aorta necessitating aortic repair with valve replacement. The characteristic feature is wrinkling or “tree-barking.” This finding is secondary to intimal fibrosis, which is common in all types of aortitis, especially Takayasu or nonspecific isolated (necrotizing) aortitis. Tree-barking is classically associated with syphilis, currently a rare cause of aortitis in developed countries. The patient had no evidence of systemic vasculitis or Takayasu disease (isolated aortitis).


Granulomatous (Giant Cell) Aortitis

The most common type of encountered aortitis is granulomatous (giant cell) aortitis. The disease may be isolated to the aorta or occur in association with a systemic syndrome. Isolated aortitis refers to cases with no history or association with other rheumatic or vasculitic diseases and represents more than half of cases of ascending aortitis.7,12 The majority of the subjects are elderly (mean age 69.1 years) although there is a large age range.6,13 Most patients are asymptomatic and are referred for aortic aneurysm repair, with aortic valve replacement required in about half of cases.

The most common autoimmune disorder associated with ascending aortitis is giant cell arteritis of the temporal artery with or without polymyalgia rheumatica (PMR). The frequency of giant cell arteritis or PMR across 8 series is 19%.2,5,6,7,8,9,10,13 Other rheumatologic disorders cause or are associated with aortitis. These include rheumatoid arthritis (˜6%), systemic lupus erythematosus (3%), inflammatory bowel disease (2% to 3%), and ankylosing spondylitis/Reiter syndrome (1%).2,5,6,7,8,9,10,13 There are also reports of associated Wegener granulomatosis, Behçet disease, polyarteritis nodosa, Cogan syndrome, Sjögren syndrome, and microscopic polyangiitis.8

Only gold members can continue reading. Log In or Register to continue

Related posts:

  1. Pediatric Interstitial Lung Disease and Hermansky-Pudlak Syndrome
  2. Pulmonary Capillaritis
  3. Small Cell Carcinoma
  4. Lymphoepithelioma-Like Carcinoma

Stay updated, free articles. Join our Telegram channel
Tags:
Aug 19, 2016 | Posted by in CARDIOLOGY | Comments Off on Aortitis

Full access? Get Clinical Tree
Get Clinical Tree app for offline access