A rare case of brain abscess caused by Actinomyces meyeri

Exploring odontogenic brain abscesses: a comprehensive review

INTRODUCTION

Whether in neurology or dentistry, odontogenic brain abscess stands as an ailment demanding undivided attention. The onset of this disease is insidious, with a relatively low incidence rate but a markedly high fatality rate. Moreover, its symptoms lack specificity, easily leading to misdiagnosis, oversight, and treatment delays. Hence, clinicians should maintain heightened vigilance when faced with pathogenic bacteria of dental origin in patients.

AREAS COVERED

This paper encapsulates the latest research findings on the clinical manifestations and essential treatment points of odontogenic brain abscess. It may offer a crucial reference for prompt diagnosis and improved therapeutic approaches.

EXPERT OPINIONS

Odontogenic brain abscess, an infection of the cerebral parenchyma, usually appears in immunocompromised patients with dental ailments or postdental surgeries. The main pathogenic microorganisms include Streptococcus intermedius, Fusobacterium nucleatum, Streptococcus anginosus, and Millerella. Given the undetectable and nonspecific symptoms in patients, the diagnostic process relies on microbiological methods. Therefore, clinicians should actively investigate and identify the pathogenic microorganisms of odontogenic brain abscess for early detection and selection of appropriate treatment regimens to avoid disease management delays.

Polymicrobial infections with specific Actinomyces and related organisms, using the current taxonomy

Actinomyces organisms reside on mucosal surfaces of the oropharynx and the genitourinary tract. Polymicrobial infections with Actinomyces organisms are increasingly being reported in the literature. Since these infections differ from classical actinomycosis, lacking of specific clinical and imaging findings, slow-growing Actinomyces organisms can be regarded as contaminants or insignificant findings. In addition, only limited knowledge is available about novel Actinomyces species and their clinical relevance. The recent reclassifications have resulted in the transfer of several Actinomyces species to novel genera Bowdeniella, Gleimia, Pauljensenia, Schaalia, or Winkia. The spectrum of diseases associated with specific members of Actinomyces and these related genera varies. In human infections, the most common species are Actinomyces israelii, Schaalia meyeri, and Schaalia odontolytica, which are typical inhabitants of the mouth, and Gleimia europaea, Schaalia turicensis, and Winkia neuii. In this narrative review, the purpose was to gather information on the emerging role of specific organisms within the Actinomyces and related genera in polymicrobial infections. These include Actinomyces graevenitzii in pulmonary infections, S. meyeri in brain abscesses and infections in the lower respiratory tract, S. turicensis in skin-related infections, G. europaea in necrotizing fasciitis and skin abscesses, and W. neuii in infected tissues around prostheses and devices. Increased understanding of the role of Actinomyces and related species in polymicrobial infections could provide improved outcomes for patient care. Key messages Due to the reclassification of the genus, many former Actinomyces species belong to novel genera Bowdeniella, Gleimia, Pauljensenia, Schaalia, or Winkia.Some of the species play emerging roles in specific infection types in humans.Increasing awareness of their clinical relevance as an established or a putative pathogen in polymicrobial infections brings about improved outcomes for patient care.

Brain abscess from oral microbiota approached by metagenomic next-generation sequencing: A case report and review of literature

BACKGROUND

Brain abscess is a serious and potentially fatal disease caused primarily by microbial infection. Although progress has been made in the diagnosis and treatment of brain abscesses, the diagnostic timeliness of pathogens needs to be improved.

CASE SUMMARY

We report the case of a 54-year-old male with a brain abscess caused by oral bacteria. The patient recovered well after receiving a combination of metagenomic next-generation sequencing (mNGS)-assisted guided medication and surgery.

CONCLUSION

Therefore, mNGS may be widely applied to identify the pathogenic microorganisms of brain abscesses and guide precision medicine.

Actinomyces meyeri-induced brain abscess in pregnancy: a case report

BACKGROUND

Brain abscesses can occur when suppurative, bacterial or protozoan infections spread to the brain. Here, we report a rare case of Actinomyces meyeri-induced brain abscess in a pregnant woman.

CASE PRESENTATION

We present the case of a 38-years-old primipara admitted to the emergency department at our hospital with a 4-day history of fever and vomiting. The symptoms worsened rapidly during the 8 h prior to admission, and the patient experienced a sudden loss of consciousness 4 h before arrival to the unit. Brain magnetic resonance imaging revealed abnormal signals in the right parietal-temporal lobe, suggesting the possibility of abscess rupture into the ventricle and sulcus. Right lateral ventricle compression and midline structure deviation to the left were noted. A right temporal-occipital mass with midline shift was detected. Emergency procedures were promptly performed, including craniotomy, removal of the right temporal-occipital mass, decompressive craniectomy, implantation of an intracranial pressure monitoring device, and external ventricular drainage. Cerebrospinal fluid culture indicated infection with Actinomyces meyeri. After administration of antibiotics, including linezolid and meropenem injections, along with treatments to decrease intracranial pressure, the patient's vital signs stabilized. However, the patient developed hydrocephalus, requiring placement of a hydrocephalus shunt several months later. Throughout this period, the patient remained in a coma vigil state, and labor was induced for the fetus.

CONCLUSIONS

Although the patient did not present with any apparent predisposing causes for brain abscess, a scout view of CT revealed dental caries. In addition, the occurrence of the brain abscess may have been influenced by the hormonal changes during pregnancy, including increased secretion of estrogen and progesterone, as well as decreased immune function. Early diagnosis and intervention are crucial in such cases. Therefore, it is recommended to seek early medical attention if symptoms such as fever, vomiting, and changes in mental state occur during pregnancy, as the prognosis for both the mother and infant is poor once the abscess ruptures.

Acute Porphyromonas gingivalis Subdural Abscess with Brain Abscess in the Left Temporal Lobe: A Case Report and Review of Literature

Background

Brain abscesses are a rare but serious complication of focal intracerebral infection.

Case Description

We present a patient of acute subdural abscess with brain abscess in the left temporal lobe. After craniotomy, combined with the Third Next Generation Sequencing and Gene Diagnosis (TNGS & GD) of abscess, we prescribed sensitive antibiotics; the patient recovers well and the abscess did not recur.

Conclusion

For patients with acute subdural abscess, combined craniotomy and the TNGS & GD of abscess could achieve good results.

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

Central nervous system (CNS) actinomycosis is a rare, serious, life-threatening, suppurative infection caused by Actinomyces species. Actinomyces are anaerobic Gram-positive bacteria, which can be normally isolated from the polymicrobial flora of the gastrointestinal- and genital tracts. They are considered very low virulent bacteria to humans. However, they can lead to several types of local or disseminated infections, if certain pathologic states or immunodeficiency occur. Intracranial abscesses caused by Actinomyces meyeri are rarely reported in adults. In this case report, we describe a 66-year-old woman who presented to the emergency department due to progressive complaints of altered sensorium and low-grade fever, due to an A. meyeri-related brain abscess. The only risk factor was represented by immunodeficiency due to the therapy with Methotrexate and steroids.

Dental Infections and Risk for Brain Abscess: A Literature Review

Dental work is commonly accepted as a low-risk procedure but has been associated with serious brain abscesses. Bacteria from the oral cavity can spread to the brain and cause life-threatening infections. In this literature review, the focus was placed on the relevant causative bacteria, surgical procedures, and correlated medical conditions revolving around brain abscesses following dental work. This paper is written from a neurological surgery perspective, using information collected from several case studies, case reviews, and other related published manuscripts. Several risk factors have been identified to predispose oral cavity bacterial infection to cause brain abscess: dental work done in the upper molars; right-to-left shunts in the heart; and poor dental hygiene. If the bacterium of the abscess is correctly identified, there is a greater effectiveness of treatment, but prolonging antibiotic and/or surgical treatment increases morbidity.

Brain complications from odontogenic infections: A systematic review

PURPOSE

Odontogenic infections can spread through different routes to more remote anatomical areas, such as the brain. Brain abscesses have an incidence of 0.3-1.3 / 100,000 population and only 2-5% are of dental origin. The main objective is to research brain complications derived from odontogenic infections. Secondary objectives were to identify the most common symptoms in brain abscess, to describe the microbiology involved in these infectious processes, report which parts of the brain complex are most commonly affected and report the sequelae of this patients.

METHODS

A systematic review following the PRISMA Guide and the Joanna Briggs Institute (JBI) Critical Appraisal Checklist for Case Reports was carried out in PubMed, Scopus and Web of Science. The search terms were: Brain infection, brain abscess, oral health oral origin, odont* infect*.

RESULTS

The database search identified a total of 1000 articles. A total of 18 publications were identified after applying inclusion and exclusion criteria. A total of 38 patients were analyzed. Mean age was 49.64±18.80 years.

CONCLUSION

The most common symptoms of patients with brain abscess are neurological affectations first and then fever and headache second, without necessarily presenting as a symptomatological triad. Microbiological diagnosis is key to determining the origin of the infection. Anaerobic pathogens such as Streptococcus (F. Milleri), Fusobacterium Nucleatum and Porfiromonas Gingivalis families are common bacterial agents. The frontal lobe is the most frequently affected, followed by the parietal and temporal lobe. The most frequent brain complications are neurological disorders. However, most patients with brain abscesses recover without sequelae.

Extensive actinomycosis with intracranial and mediastinal involvement: a therapeutic challenge

Central nervous system (CNS) involvement by actinomycosis is rare, seen in 2%–3% cases. It mostly spreads to CNS by haematogenous route from a distant primary site such as oral cavity, lung, abdomen or pelvis. Direct CNS extension can also occur. It mostly presents as brain abscess, meningoencephalitis, actinomycetoma, subdural empyema and epidural abscess. We report one case of extensive actinomycosis having intra and extraparenchymal CNS, spinal canal, retropharyngeal and mediastinal involvement. Due to such widespread extension and involvement of vital areas, complete surgical debulking was not possible. In addition to therapeutic resistance to conventional antibiotics, repetitive negative cultures posed significant difficulty in the case management.

Clinico-microbiological spectrum of anaerobic pyogenic infections in an Indian tertiary care teaching hospital: A two-year study

Introduction:

Anaerobes are important however the most neglected pathogens. Timely isolation of anaerobes can guide the clinician about the correct course of clinical treatment and thus reduce the mortality and also the problem of antimicrobial resistance.

Materials and Methods:

Tissue and/or pus aspirates were collected aseptically from infectious sites in the Robertson's cooked meat medium (RCM) and sent to anaerobic bacteriology laboratory for culture. Subcultures from RCM for each sample were done on neomycin blood agar and 5% sheep blood agar along with metronidazole disc (5μg). The plates were incubated in an anaerobic jar using GasPak for 72 hrs. The preliminary identification was performed by standard biochemical tests for both obligate and facultative anaerobic isolates. Speciations of obligate anaerobes were performed by Vitek 2 automated system.

Results:

Obligate anaerobes either single or polymicrobial were obtained in 38/216 (14.5 %) samples processed during the study period. Polymicrobial infections were reported in 21/216 (55.26%) samples and most commonly with obligate anaerobic gramnegative bacilli i.e. Prevotella-Porphyromonas and Bacteroides fragilis group. Most common monomicrobial anaerobic infections were observed with Veillonella spp. (n=4) and Porphyromonas spp. (n=4) followed by Bacteroides fragilis (n=3). Obligate anaerobes were predominantly isolated from skin and soft tissue infections (n=14) followed by surgical site infections (n=8).

Conclusion:

Although most of the infections are polymicrobial, a rise in the incidence of monomicrobial anaerobic infections has been noticed. Therefore, the performance of anaerobic cultures along with aerobic cultures is much needed for complete bacterial work-up of specimens from infectious sites and better patient management.