The epidemiology, clinical presentation and treatment outcomes in CNS actinomycosis: a systematic review of reported cases

Abstract

Background CNS actinomycosis is a rare chronic suppurative infection with non-specific clinical features. Diagnosis is difficult due to its similarity to malignancy, nocardiosis and other granulomatous diseases. This systematic review aimed to evaluate the epidemiology, clinical characteristics, diagnostic modalities and treatment outcomes in CNS actinomycosis. Methods The major electronic databases (PubMed, Google Scholar, and Scopus) were searched for the literature review by using distinct keywords: "CNS" or "intracranial" or "brain abscess" or "meningitis" OR "spinal" OR "epidural abscess" and "actinomycosis." All cases with CNS actinomycosis reported between January 1988 to March 2022 were included. Results A total of 118 cases of CNS disease were included in the final analysis. The mean age of patients was 44 years, and a significant proportion was male (57%). Actinomycosis israelii was the most prevalent species (41.5%), followed by Actinomyces meyeri (22.6%). Disseminated disease was found in 19.5% of cases. Most commonly involved extra-CNS organs are lung (10.2%) and abdomen (5.1%). Brain abscess (55%) followed by leptomeningeal enhancement (22%) were the most common neuroimaging findings. Culture positivity was found in nearly half of the cases (53.4%). The overall case-fatality rate was 11%. Neurological sequelae were present in 22% of the patients. On multivariate analysis, patients who underwent surgery with antimicrobials had better survival (adjusted OR 0.14, 95% CI 0.04–0.28, p value 0.039) compared to those treated with antimicrobials alone. Conclusion CNS actinomycosis carries significant morbidity and mortality despite its indolent nature. Early aggressive surgery, along with prolonged antimicrobial treatment is vital to improve outcomes.

Actinomyces meyeri Causing Cerebral Abscess in a Patient on Methotrexate: A Rare Case Report and Systematic Review of the Literature

“…To the best of our knowledge, this is the first case of a A. meyeri related brain abscess, where the only risk factor was represented by the immunodeficiency due to the therapy with MTX and steroids. As above mentioned, it should be noted that, in contrast to the common Actinomycosis imitators, such as Nocardia and tuberculosis, which also may cause cerebral pathology, CNS actinomycosis is not usually associated with immunodeficiency [ 1 ].…”

“…There is only a few literature on virulence factors of Actinomyces species. The existing data suggest that they are not producing classical exotoxins and are probably able to evade the host immune clearance-surveillance in immuno-competent patients [ 1 ]. For this reason, patients on immune modulating drugs may be prone to develop infections at a higher risk.…”

“…Central nervous system (CNS) actinomycosis is a rare suppurative infection that manifests itself by non-specific signs. In contrast to systemic actinomycosis, CNS actinomycosis is not usually associated with immunodeficiency [ 1 ], and in most cases, its pathogenetic mechanism is hematogenous spread or local extension of cervicofacial actinomycosis. The most common clinical presentation of CNS actinomycosis is an abscess (67%), followed by meningitis or meningoencephalitis (13%), actinomycoma (7%), subdural empyema (6%), and epidural abscess (6%) [ 1 , 2 ].…”

Diagnostic Performance of central nervous system infections in patients with neurosurgical intensive care using metagenomic next-generation sequencing: A Prospective Observational Study

“…The incidence rate of extraventricular drainage-related infection was reported to be 8% to 22%, while craniocerebral trauma and lumbar cistercius drainage were 1.4% and 5% (2). Central nervous system infections lead to high morbidity and mortality (3)(4)(5). The infections also lead to long-term implications, such as neurological deficits.…”