Non-Tuberculous Mycobacterium Induced Pseudoaneurysm of the Common Carotid Artery

Infective Native Extracranial Carotid Artery Aneurysms: A Systematic Review

BACKGROUND

Infective native extracranial carotid artery aneurysms are rare, and their management is variable due to a lack of evidence assessing outcomes.

METHODS

We performed a systematic literature review following PRISMA guidelines to identify all reported cases of infective native extracranial carotid artery aneurysms between January 1970 and March 2021.

RESULTS

This study identified 193 infective native aneurysms of the extracranial carotid artery from 154 sources. Patients were predominantly male (71.4%), and age ranged from 6 months to 89 years old. The most common presenting features were a neck mass and fever, but also included hemorrhage, respiratory distress, and neurological symptoms. Most aneurysms were located in the internal carotid artery (47.4%). Staphylococcus (23.3%) was the most commonly identified causative pathogen, followed by Mycobacterium tuberculosis (20.9%). Most appeared to become infected by direct local spread. Treatment strategies involved open surgical methods in 101 cases and an endovascular approach in 41 cases. In 4 cases, a hybrid method involving concurrent endovascular and open surgical management was undertaken. In 5 cases, there was antibiotic treatment alone. In the open surgery-treated group, the complication rate was 20.8% compared to 13.2% in the endovascular group. Mortality rate was 5.6%.

CONCLUSIONS

Our review identified 193 cases of infective native extracranial carotid artery aneurysms. Direct local spread of a staphylococcus infection was the commonest cause. Endovascular management was associated with fewer early complications than open surgical management.

A case of idiopathic extracranial carotid artery pseudoaneurysm with a rare clinical course and pathological features

Extracranial carotid artery aneurysms (ECAAs) are rare, with the etiology mainly classified as degeneration or dissection. Pseudoaneurysms in the region are even rarer and are seen following trauma, iatrogenic injury, or infection. We report a case of extracranial carotid artery pseudoaneurysm (pseudo-ECAA) with a rare clinical course and pathological features. A 58-year-old man presented with swelling and purpura on the left side of his neck after sneezing. Radiological examinations suggested a ruptured left common carotid artery aneurysm. The operative findings were consistent with a pseudoaneurysm. Pathological examination revealed disarrangement and degeneration of smooth muscle fibers in the media, in addition to scattered foci of mucoid accumulation and irregular-shaped cavitation in the medial extracellular matrix, raising the possibility of an intrinsic dysfunction of the vascular wall in the pathological process of pseudoaneurysm formation.