Ruptured Mycotic Cerebral Aneurysm Secondary to Disseminated Nocardiosis

A rare case of ruptured anterior cerebral artery infected aneurysm with angioinvasion secondary to disseminated Nocardia otitidiscaviarum: A case report and literature review

Background:

The cases of ruptured infected aneurysms secondary to disseminated nocardiosis are exceptionally rare. Therefore, there is no guideline for investigation or optimal treatment.

Case Description:

A 51-year-old man with immunocompromised status was first presented with pneumonia and cerebral infarction, where the infected aneurysm was ruptured thereafter. Intraoperative findings revealed left anterior cerebral artery thrombosis and occlusion with evidence of angioinvasion along with pus discharge which was later identified with Nocardia otitidiscaviarum. Our case was the first to report on the angioinvasive nature of cerebral nocardiosis, which occurs concurrently with a ruptured infected aneurysm and an unusual presentation that made the diagnosis and treatment challenging.

Conclusion:

Cerebral nocardiosis may cause ruptured infected aneurysms in patients with risk factors, especially for immunocompromised hosts. Furthermore, Nocardia can present with severe cerebral manifestation due to angioinvasion causing cerebral infarction accompanied by a ruptured infected aneurysm.

Infective endocarditis by Nocardia species: a systematic review

Nocardiosis, is a potentially life-threatening disease, especially in immunocompromised individuals where it manifests as a disseminated disease. Infective Endocarditis (IE) is a rare disease with significant morbidity and mortality. Importantly, even though there are scarce data of IE by Nocardia spp. in the literature, a review adequately summarizing systematically all available evidence on the topic is lacking. The aim of this study was to systematically review all cases of IE by Nocardia spp. and describe the epidemiology, microbiology, clinical characteristics, treatment and outcomes of this infection. A systematic review of PubMed, Scopus and Cochrane library (through 7 December 2021) for studies providing epidemiological, clinical, microbiological as well as treatment data and outcomes of patients with IE by Nocardia spp. was performed. A total of 25 studies providing data for 26 patients were included. A prosthetic valve was present in 30.8%, while the most common microorganism was N. asteroides. Aortic valve was the most commonly infected intracardiac site, followed by the mitral valve. Diagnosis was most commonly performed with transthoracic echocardiography, while the diagnosis was made at autopsy in 11.5%. Co-trimoxazole, aminoglycosides and carbapenems were the most commonly used antimicrobials. Clinical cure was noted in 73.1%, while mortality was 26.9%. This systematic review thoroughly describes IE by Nocardia and provides information on epidemiology, clinical presentation, treatment and outcomes.