Pyogenic brain abscess and subdural empyema: presentation, management, and factors predicting outcome

Otogenic Brain Abscess and Concomitant Acute COVID-19 Infection: Case Report and Review of the Literature

BACKGROUND

 2019 coronavirus disease (COVID-19) has attracted global attention primarily because of the severe acute respiratory symptoms associated with it. However, nearly one third of the patients also present with neurological symptoms. This report describes a case of a previously healthy woman with acute COVID-19 infection, who developed acute facial nerve palsy and rapid progression to coma due to otogenic brain abscess.

CASE DESCRIPTION

 A 63-year-old woman with acute COVID-19 infection exhibited acute facial nerve paresis, high fever, and purulent secretion from her left ear within 48 hours after COVID-19 onset. Cranial computed tomography scan confirmed acute mastoiditis, precipitating an urgent mastoidectomy. A postoperative contrast-enhanced magnetic resonance imaging on the same day revealed a subdural empyema, which prompted an urgent craniotomy and decompression. Intraoperative microbiological swabs confirmed a Streptococcus pyogenes infection; however, reverse transcription polymerase chain reaction was negative for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). After immediate intravenous antibiotic treatment, extubation was achieved 4 days after operation, and the patient was discharged without neurological deficits 19 days after postoperatively.

CONCLUSION

 This finding adds a layer of insight into the specific nature of the infection, suggesting a potential absence of SARS-CoV-2 involvement in otogenic subdural empyema. However, the impact of SARS-CoV-2 in otogenic brain abscess cannot be excluded to date and should be further prospectively investigated. The complete recovery of neurological status emphasizes the importance of prompt and interdisciplinary interventions in managing rare and severe complications associated with COVID-19.

Impact of the COVID-19 pandemic on the incidence of pediatric intracranial empyemas in Spain

INTRODUCTION

Intracranial infections due to sinusitis and otitis, although rare, can progress rapidly and result in significant morbidity, necessitating multifaceted management including extended antibiotic therapy and surgical intervention. Predominantly affecting infants and older children, these infections have seen a perceived increase in incidence following the coronavirus disease 2019 (COVID-19) pandemic.

OBJECTIVES

Our study aims to describe the clinical and epidemiological characteristics of intracranial infections secondary to sinusitis or otitis in the pediatric population and assess changes in incidence and clinical presentation post-pandemic. Specific objectives include analyzing neurosurgical management practices, the role of ENT-neurosurgery cooperation, incidence of epileptic seizures, and management of associated venous thrombosis.

MATERIALS AND METHODS

A retrospective multicentric study was conducted in hospitals across the Iberian Peninsula, including data from January 2018 to December 2022. Data were divided into pre-lockdown (January 2018 to March 2020) and post-lockdown (March 2020 to December 2022) periods for analysis.

RESULTS

The study included 60 pediatric cases (38 post-pandemic and 22 pre-pandemic). The average age was 9.8 years, with a male predominance (61.67%). Sinusitis was the most frequent cause (86%), and the frontal region was the most common site of infection (75%). Neurological symptoms were more prevalent post-pandemic (55.26% versus 23.68%). The primary pathogen was S. intermedius (29.6%). Most patients required neurosurgical intervention (81.7%), with a significant portion undergoing combined ENT-neurosurgery procedures (52.9%). The average antibiotic treatment duration was 6.6 weeks. Complications included venous sinus thrombosis (20%) and seizures (39.2%). Mortality was 3.3%.

CONCLUSION

Although there was a perceived increase in cases post-pandemic, our study observed a normalization of incidence after the lockdown, with a decrease in diagnoses during confinement. The accepted antibiotic regimen lasts 6 weeks, extendable to 8 weeks in non-surgical patients, with at least 2 weeks of intravenous treatment. Sinus surgery combined with antibiotics may suffice to avoid craniotomy in some cases, while combined surgery has a lower reoperation rate in others. Anticoagulation should be individualized and discontinued upon recanalization. Prophylactic antiepileptic drug use remains controversial and should be tailored to patients with specific risk factors. Prolonged antiepileptic drug (AED) therapy may be warranted for those with early seizures and hemorrhagic lesions, whereas others may gradually taper off AEDs after the acute stage.

Streptococcus intermedius: an underestimated pathogen in brain infection?

Streptococcus intermedius is an oral commensal organism belonging to the Streptococcus anginosus group (SAG). S. intermedius causes periodontitis as well as invasive, pyogenic infection of the central nervous system, pleural space or liver. Compared with other SAG organisms, S. intermedius has a higher mortality as well as a predilection for intracranial infection, suggesting it is likely to possess virulence factors that mediate specific interactions with the host resulting in bacteria reaching the brain. The mechanisms involved are not well described. Intracranial suppuration (ICS) due to S. intermedius infection can manifest as an abscess within the brain parenchyma, or a collection of pus (empyema) in the sub- or extra-dural space. These infections necessitate neurosurgery and prolonged antibiotic treatment and are associated with a considerable burden of morbidity and mortality. The incidence of ICS is increasing in several settings, with SAG species accounting for an increasing proportion of cases. There is a paucity of published literature regarding S. intermedius pathogenesis as well as few published genomes, hampering molecular epidemiological research. This perspective evaluates what is known about the clinical features and pathogenesis of ICS due to S. intermedius and explores hypothetical explanations why the incidence of these infections may be increasing.

Microbial Analyses of Subdural Empyema: A Case Report and Literature Review

Subdural empyema (SDE) is an infection between the dura and arachnoid mater, presenting with symptoms such as fever, headache, altered sensorium, neurological deficits, and seizures. Due to its rapidly progressive nature, early diagnosis and treatment are crucial. This paper aims to identify common pathogens, imaging findings, and the necessity of emergent neurosurgical intervention. We present the case of a 49-year-old woman with an SDE who underwent craniotomy to evacuate pus and hematoma. Cultures confirmed Streptococcus intermedius, and the patient improved postoperatively with the complete evacuation of the SDE and resolution of midline shift seen on the CT scan. A PubMed literature review focused on consolidating data to identify common pathogens, demographic details, treatment methods and duration, and outcomes in SDE. SDE requires prompt diagnosis and treatment. Contrast-enhanced brain MRI is crucial for diagnosis, showing features distinct from subdural hematoma or hygroma. Neurosurgical intervention is urgent, including craniotomy and evacuation. Postoperative broad-spectrum antibiotic therapy is essential until specific pathogens are identified, and a multidisciplinary approach is recommended.

Otogenic brain complications: a systematic review and meta-analysis

OBJECTIVE

This study aimed to form astute deductions regarding the presentation, treatment and mortality of otogenic brain complications.

METHODS

A systematic literature search of four medical databases (PubMed, Embase, Web of Science and Scopus) was conducted. Studies associated with otogenic brain complications were considered eligible. Fixed- and random-effects model meta-analysis was developed to assess the proportion estimate for each outcome individually.

RESULTS

Twenty-eight studies, with 1650 patients in total, were included. In 66 per cent of patients there was a known history of chronic otitis media. The most common symptoms were purulent otorrhoea (84 per cent), headache (65 per cent) and otalgia (45 per cent). A brain abscess was observed in 49 per cent of patients, followed by meningitis (34 per cent) and sinus thrombosis (22 per cent). A combination of surgical and conservative therapy was chosen in 84.3 per cent of cases and the mortality rate approached 11.1 per cent.

CONCLUSION

Otogenic brain complications are a possibly life-threatening condition. Prompt imaging examination may set the final diagnosis and lead to an effective treatment.

A Rare Confluence: Brain Abscess in an Adult With Tetralogy of Fallot

Tetralogy of Fallot (TOF) is a common congenital heart disease (CHD) characterized by four distinct cardiac abnormalities. Brain abscess, though rare, is a life-threatening complication in patients with cyanotic congenital heart disease (CCHD), including TOF. This case report describes a 24-year-old female with unrepaired TOF who presented with symptoms of a brain abscess, including altered sensorium, fever, projectile vomiting, and headache. Diagnostic imaging with non-contrast-enhanced computed tomography (NCCT) revealed a well-defined hypodense lesion with a midline shift, prompting urgent drainage of the abscess. Subsequent cultures of the pus material identified Streptococcus intermedius as the causative agent, and the patient was maintained on antibiotics. This case highlights the importance of early diagnosis and surgical repair of TOF to prevent severe complications such as brain abscess, thereby reducing morbidity and mortality.

Endoscopic Access to Brain Abscess Due to Sinonasal Infection

BACKGROUND

Brain abscesses caused by sinonasal infections have become more common during the coronavirus pandemic, particularly due to the increase in sinonasal mucormycosis. This study aimed to evaluate the efficacy and safety of endoscopic endonasal brain abscess drainage as a therapeutic technique for these cases.

METHODS

Clinical outcomes and retrospective evaluations were performed in patients who underwent endoscopic endonasal brain abscess drainage between May 2019 and August 2022. A total of 7 patients diagnosed with 9 brain abscesses caused by sinonasal infections were included in the study. The main outcome of this study was to evaluate the success and safety of this technique.

RESULTS

The average age of the patients was 40.71 ± 14.17 years. The most common symptom observed in these patients was nasal discharge, and the frontal lobe was the most common site of abscess. Notably, the majority of cases were associated with COVID-19.

CONCLUSIONS

Based on the results of this study, endoscopic endonasal brain abscess drainage is considered a viable treatment option for skull base brain abscesses caused by sinonasal infections. Further research in this field can help establish this technique as a mainstay approach for managing brain abscesses at the skull base.

European society of Clinical Microbiology and Infectious Diseases guidelines on diagnosis and treatment of brain abscess in children and adults

SCOPE

These European Society of Clinical Microbiology and Infectious Diseases guidelines are intended for clinicians involved in diagnosis and treatment of brain abscess in children and adults.

METHODS

Key questions were developed, and a systematic review was carried out of all studies published since 1 January 1996, using the search terms 'brain abscess' OR 'cerebral abscess' as Mesh terms or text in electronic databases of PubMed, Embase, and the Cochrane registry. The search was updated on 29 September 2022. Exclusion criteria were a sample size <10 patients or publication in non-English language. Extracted data was summarized as narrative reviews and tables. Meta-analysis was carried out using a random effects model and heterogeneity was examined by I2 tests as well as funnel and Galbraith plots. Risk of bias was assessed using Risk Of Bias in Non-randomised Studies - of Interventions (ROBINS-I) (observational studies) and Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) (diagnostic studies). The Grading of Recommendations Assessment, Development and Evaluation approach was applied to classify strength of recommendations (strong or conditional) and quality of evidence (high, moderate, low, or very low).

QUESTIONS ADDRESSED BY THE GUIDELINES AND RECOMMENDATIONS

Magnetic resonance imaging is recommended for diagnosis of brain abscess (strong and high). Antimicrobials may be withheld until aspiration or excision of brain abscess in patients without severe disease if neurosurgery can be carried out within reasonable time, preferably within 24 hours (conditional and low). Molecular-based diagnostics are recommended, if available, in patients with negative cultures (conditional and moderate). Aspiration or excision of brain abscess is recommended whenever feasible, except for cases with toxoplasmosis (strong and low). Recommended empirical antimicrobial treatment for community-acquired brain abscess in immuno-competent individuals is a 3rd-generation cephalosporin and metronidazole (strong and moderate) with the addition of trimethoprim-sulfamethoxazole and voriconazole in patients with severe immuno-compromise (conditional and low). Recommended empirical treatment of post-neurosurgical brain abscess is a carbapenem combined with vancomycin or linezolid (conditional and low). The recommended duration of antimicrobial treatment is 6-8 weeks (conditional and low). No recommendation is offered for early transition to oral antimicrobials because of a lack of data, and oral consolidation treatment after ≥6 weeks of intravenous antimicrobials is not routinely recommended (conditional and very low). Adjunctive glucocorticoid treatment is recommended for treatment of severe symptoms because of perifocal oedema or impending herniation (strong and low). Primary prophylaxis with antiepileptics is not recommended (conditional and very low). Research needs are addressed.

Pertinence of Streptococcus anginosus group in intracerebral abscesses in the era of extended antibiotic resistance

AIMS

• To study the incidence of Streptococcus anginosus group (SAG) in pyogenic or community acquired intra cerebral abscess. • To understand the risk factors for the same. • To analyze the specific radiological features and clinical outcome after surgery and antibiotic therapy.

METHODS

This is a retrospective observational study of case series over a period of one year. Patients diagnosed with intracerebral abscess were included in the study. Pus collected from were received in the laboratory and processed according to the standard protocols. Data regarding the clinical findings and demographics were collected from medical records.

FINDINGS

A total of 202 samples were studied. 103 were found to be pyogenic. SAG were isolated from 21 samples (20.38%) and all the isolates were sensitive to Penicillin. Age of the patients ranged from 18months to 68years. Male preponderance was noted with male to female ratio of 4:1. Otogenic infections were the most common predisposing factors and focus of infection could not be ascertained in 5 patients. All patients were treated with surgical intervention and antibiotics (Vancomycin, Amikacin and Metronidazole) for 6 weeks and recovery was remarkable. One patient succumbed to the illness.

CONCLUSION

SAG can be an aggressive pathogen with propensity for abscess formation. Chronic Suppurative Otitis Media (CSOM) is still a major cause of intracerebral abscess in developing country like India which is a benign and curable disease and should not be neglected. Injudicious use of antibiotics and negligence regarding the dose and duration of therapy from both patients and health care providers is the major cause for common infections to become more difficult to treat and succumbing to complications.

Cryptogenic Pontine Abscess Treated With Stereotactic Aspiration: A Case Report

Brainstem abscesses are localized collections of pus or infected material within the brainstem, which can cause inflammation, tissue damage, and compression of adjacent structures. This can lead to a variety of symptoms, including headache, fever, and focal neurological deficits, among many others. Brainstem abscesses are potentially life-threatening and considered to be rare, and pontine abscesses are even rarer. Both are often caused by the spread of infection from nearby structures like the middle ear, sinuses, and mastoid air cells, but they can also result from distant infectious sites that have spread to the bloodstream. Ambiguous clinical presentation can delay appropriate care and lead to poorer outcomes. We present a rare case of pontine abscess in a 54-year-old male with both undetermined causal origins and unclear infectious signs, namely, the lack of fever, fatigue, and chills. We will discuss the etiologies, diagnosis, and treatment of cryptogenic brainstem lesions in this case report.

Clinical infections in neurosurgical oncology: An overview

Central nervous system (CNS) infections are urgent conditions with high morbidity and mortality. Bacteria, viruses, parasites or fungi can cause them. Intracranial infections after craniotomies are an important complication of treatment, especially in oncological patients that are already immunologically compromised due to the disease and treatment. The consequence of CNS infections in oncological patients includes longer treatment with antibiotics, additional surgical procedures, higher treatment costs and poorer treatment outcomes. Additionally, the management of primary pathology may be prolonged or postponed as a result of the active infection. By introducing new and improved protocols, tightening controls on their implementation, constantly educating the entire team involved in patient treatment and educating both patients and relatives, the incidence of infections can be reduced effectively.

Clinical and radiological characteristics of brain abscess due to different organisms in hospitalized patients: A 6-year retrospective study from China

Background

Brain abscess (BA) is a rare but life-threatening infection. Early identification of the pathogen is helpful to improve the outcomes. This study aimed to describe the clinical and radiological features of patients with BA caused by different organisms.

Methods

A retrospective, observational study of patients with known etiologic diagnosis of BA in Huashan Hospital Affiliated to Fudan University in China between January 2015 and December 2020 was conducted. Data on patient demographics, clinical and radiological presenting features, microbiological results, surgical treatment, and outcomes were collected.

Results

Sixty-five patients (49 male, 16 female) with primary BAs were included. Frequent clinical presentations included headache (64.6%), fever (49.2%) and confusion (27.3%). Streptococcus viridans was associated with thicker wall of abscesses (6.94 ± 8.43 mm for S. viridans versus 3.66 ± 1.74 mm for other organisms, P = 0.031) and larger oedema (89.40 ± 15.70 mm for S. viridans versus 74.72 ± 19.70 mm for other organisms, P = 0.023). The independent factor associated with poor outcome identified by multivariate analysis was confusion (Odds ratio 6.215, 95% confidence interval 1.406-27.466; P = 0.016).

Conclusions

Patients with BAs caused by Streptococcus species had nonspecific clinical signs, but specific radiological features, which might be helpful for early diagnosis.

Development of subdural empyema from subdural effusion after suppurative encephalitis: A case report

BACKGROUND

Chronic subdural effusion is very common in the cranial imaging of middle-aged and older people. Herein, we report a patient misdiagnosed with subdural effusion, who was eventually diagnosed with chronic subdural empyema (SDE) caused by Streptococcus pneumoniae.

CASE SUMMARY

A 63-year-old man was brought to our emergency room with a headache, vomiting, and disturbed consciousness. Computed tomography (CT) revealed a bilateral subdural effusion at the top left side of the frontal lobe. Cerebrospinal fluid examination after lumbar puncture indicated suppurative meningitis, which improved after anti-infective therapy. However, the patient then presented with acute cognitive dysfunction and right limb paralysis. Repeat CT showed an increase in left frontoparietal subdural effusion, disappearance of the left lateral ventricle, and a shift of the midline to the right. Urgent burr hole drainage showed SDE that was culture-positive for Streptococcus pneumoniae. His condition improved after adequate drainage and antibiotic treatment.

CONCLUSION

Patients with unexplained subdural effusion, especially asymmetric subdural effusion with intracranial infection, should be assessed for chronic SDE. Early surgical treatment may be beneficial.

Spontaneous empyema and brain abscess in an intensive care population: clinical presentation, microbiology, and factors associated with outcome

BACKGROUND

Data on critically ill patients with spontaneous empyema or brain abscess are limited. The aim was to evaluate clinical presentations, factors, and microbiological findings associated with the outcome in patients treated in a Neurocritical Care Unit.

METHODS

In this retrospective study, we analyzed 45 out of 101 screened patients with spontaneous epidural or subdural empyema and/or brain abscess treated at a tertiary care center between January 2012 and December 2019. Patients with postoperative infections or spinal abscess were excluded. Medical records were reviewed for baseline characteristics, origin of infection, laboratory and microbiology findings, and treatment characteristics. The outcome was determined using the Glasgow outcome scale extended (GOSE).

RESULTS

Favorable outcome (GOSE 5-8) was achieved in 38 of 45 patients (84%). Four patients died (9%), three remained severely disabled (7%). Unfavorable outcome was associated with a decreased level of consciousness at admission (Glasgow coma scale < 9) (43% versus 3%; p = 0.009), need of vasopressors (71% versus 11%; p = 0.002), sepsis (43% versus 8%; p = 0.013), higher age (65.1 ± 15.7 versus 46.9 ± 17.5 years; p = 0.014), shorter time between symptoms onset and ICU admission (5 ± 2.4 days versus 11.6 ± 16.8 days; p = 0.013), and higher median C-reactive protein (CRP) serum levels (206 mg/l, range 15-259 mg/l versus 17.5 mg/l, range 3.3-72.7 mg/l; p = 0.036). With antibiotics adapted according to culture sensitivities in the first 2 weeks, neuroimaging revealed a progression of empyema or abscess in 45% of the cases.

CONCLUSION

Favorable outcome can be achieved in a considerable proportion of an intensive care population with spontaneous empyema or brain abscess. Sepsis and more frequent need for vasopressors, associated with unfavorable outcome, indicate a fulminant course of a not only cerebral but systemic infection. Change of antibiotic therapy according to microbiological findings in the first 2 weeks should be exercised with great caution.

A 42-Year-Old Man with a Seizure

A 42-Year-Old Man with a SeizureA 42-year-old man with acute myeloid leukemia presented for evaluation after an episode of convulsions. Six weeks before this event, he had a cough productive of yellow sputum. Two weeks later, he started having a headache and fevers. How do you approach the evaluation, and what is the diagnosis?

Trends of Antimicrobial Susceptibility in Clinically Significant Coagulase-Negative Staphylococci Isolated from Cerebrospinal Fluid Cultures in Neurosurgical Adults: a Nine-Year Analysis

Coagulase-negative staphylococci (CoNS) are the main pathogens in health care-associated ventriculitis and meningitis (HCAVM). This study aimed to assess antimicrobial susceptibility. Moreover, the treatment and clinical outcome were described. All neurosurgical adults admitted to one of the largest neurosurgical centers in China with clinically significant CoNS isolated from cerebrospinal fluid cultures in 2012 to 2020 were recruited. One episode was defined as one patient with one bacterial strain. Interpretive categories were applied according to the MICs. The clinical outcomes were dichotomized into poor (Glasgow Outcome Scale 1 to 3) and acceptable (Glasgow Outcome Scale 4 to 5). In total, 534 episodes involving 519 patients and 16 bacteria were analyzed. Over the 9 years, eight antimicrobial agents were used in antimicrobial susceptibility tests, including six in over 80% of CoNS. The range of resistance rates was 0.8% to 84.6%. The vancomycin resistance rate was the lowest, whereas the penicillin resistance rate was the highest. The linezolid (a vancomycin replacement) resistance rate was 3.1%. The rate of oxacillin resistance, representing methicillin-resistant staphylococci, was 70.2%. There were no significant trends of antimicrobial susceptibility over the 9 years for any agents analyzed. However, there were some apparent changes. Notably, vancomycin-resistant CoNS appeared in recent years, while linezolid-resistant CoNS appeared early and disappeared in recent years. Vancomycin (or norvancomycin), the most common treatment agent, was used in 528 (98.9%) episodes. Finally, 527 (98.7%) episodes had acceptable outcomes. It will be safe to use vancomycin to treat CoNS-related HCAVM in the immediate future, although continuous monitoring will be needed. IMPORTANCE Coagulase-negative staphylococci are the main pathogens in health care-associated ventriculitis and meningitis. There are three conclusions from the results of this study. First, according to antimicrobial susceptibility, the rates of resistance to primary antimicrobial agents are high and those to high-level agents, including vancomycin, are low. Second, the trends of resistance rates are acceptable, especially for high-level agents, although long-term and continuous monitoring is necessary. Finally, the clinical outcomes of neurosurgical adults with coagulase-negative staphylococci-related health care-associated ventriculitis and meningitis are acceptable after treatment with vancomycin. Therefore, according to the antimicrobial susceptibility and clinical practice, vancomycin will be safe to treat coagulase-negative staphylococci-related health care-associated ventriculitis and meningitis.

Sequential Intravenous-Oral Therapy for Pediatric Streptococcus anginosus Intracranial Infections

Background

Streptococcus anginosus group is a common cause of pediatric intracranial infections but treatment recommendations, including use of oral therapy, are poorly defined.

Methods

We performed a retrospective review from 2004 to 2019 of all patients with S anginosus group pyogenic intracranial infections at Children's Hospital Colorado, highlighting patients transitioned to oral therapy. The primary endpoint was worsening infection necessitating intravenous antibiotics or a source control procedure after transition to oral therapy.

Results

Of 107 patients with S anginosus intracranial infections, 61 were transitioned to exclusive oral therapy after a median intravenous duration of 37 days, overwhelmingly with a levofloxacin-based regimen. Only 1 treatment failure was noted in a patient who did not fill their prescription. Patients with epidural infections were more likely to be transitioned to oral therapy within the first 28 days of treatment (defined as "early"). Patients with parenchymal infections, bacteremia, co-pathogens, higher inflammatory markers, and requiring >1 source control procedure were less likely to be transitioned early to oral therapy. Complications of a central catheter and/or intravenous medications contributed to 56% of oral transitions.

Conclusions

Levofloxacin-based oral regimens were effective and well tolerated. Patients with less severe infections were more likely to be transitioned early to oral therapy. Criteria for transitioning patients to oral antibiotics for intracranial infections should be established to minimize risks inherent with central catheters.

Unusual intracranial suppuration: illustrative cases

BACKGROUND

Intracranial suppuration (ICS) is a rare complication that can arise from various disease processes and is composed of brain abscess, extradural empyema, and subdural empyema. Although significant progress has been achieved with antibiotics, neuroimaging, and neurosurgical technique, ICS remains a serious neurosurgical emergency. An uncommon presentation of ICS is sterile ICS, which has yet to be fully elucidated by clinicians. The authors present 2 cases of unusual sterile ICS: a sterile subdural empyema and a sterile brain abscess.

OBSERVATIONS

Both patients underwent surgical treatment consisting of craniotomy to evacuate the pus collection. The blood cultures from both the patients, the collected empyema, and the thick capsule from the brain abscess were sterile. However, the necrotic brain tissue surrounding the abscess contained inflammatory cells. The authors’ review of the literature emphasizes the rarity of sterile ICS and substantiates the necessity for additional studies to explore this field.

LESSONS

Sterile ICS is a disease entity that warrants further investigation to determine appropriate treatment to improve patient outcomes. This study highlights the paucity of data available regarding sterile ICS and supports the need for future studies to uncover the etiology of sterile ICS to better guide management of this condition.

From prostate to the pons: The first reported case of multi-organ septic emboli and brain empyema from an untreated prostate abscess

Prostate abscesses in developed countries are becoming increasingly less common. Left untreated these abscesses can lead to numerous complications, including some which are very rare.

Cerebral Abscess Caused by Listeria monocytogenes: Case Report and Literature Review

BACKGROUND

 Listeria monocytogenes is an opportunistic gram-positive, facultative intracellular bacterium that causes invasive diseases mostly in pregnant women and immunosuppressed patients. Despite the predilection toward the central nervous system (CNS), it usually causes meningitis and meningoencephalitis, whereas brain abscesses are very uncommon.

CASE PRESENTATION

 We describe the case of a 69-year-old homeless patient with a brain abscess due to L. monocytogenes who was successfully treated surgically by a guided stereotactic aspiration and antibiotic therapy with ampicillin and gentamicin. Our patient was discharged after 4 weeks of therapy without neurologic deficits. Additionally, we provide a review of the literature of brain abscesses caused by L. monocytogenes.

CONCLUSIONS

 This case highlights the need to drain cerebral abscesses and culture pus to correctly treat patients with antibiotics, especially given the high mortality rate of this infectious entity.

Risk Factors for Brain Abscess: A Nationwide, Population-Based, Nested Case-Control Study

BACKGROUND

Knowledge on risk factors for brain abscess is limited and relies on single-center cohort studies.

METHODS

We accessed nationwide medical registries to conduct a population-based, nested case-control study of risk factors for brain abscess. We applied risk-set sampling for the selection of population controls (1:10), who were individually matched by age, sex, and area of residence. Conditional logistic regression was used to compute adjusted odds ratios (aOR) with 95% confidence intervals (CIs). Population-attributable fractions were calculated.

RESULTS

We identified 1384 brain abscess patients in Denmark from 1982 through 2016, and 13 839 matched population controls. The median age of patients was 50 years (interquartile range 33-63) and 37% were female. Cases often had Charlson comorbidity scores >2 (16%), compared with controls (3%). Our calculated aORs were 2.15 (95% CI 1.72-2.70) for head trauma; 19.3 (95% CI 14.3-26.0) for neurosurgery; 4.61 (95% CI 3.39-6.26) for dental infections; 2.57 (95% CI 1.71-3.84) for dental surgery; 3.81 (95% CI 3.11-4.67) for ear, nose, and throat infection; 2.85 (95% CI 2.21-3.70) for ear, nose, and throat surgery; 15.6 (95% CI 9.57-25.4) for congenital heart disease; 1.74 (95% CI 1.33-2.29) for diabetes mellitus; 2.22 (95% CI 1.58-3.11) for alcohol abuse; 2.37 (95% CI 1.53-3.68) for liver disease; 2.04 (95% CI 1.30-3.20) for kidney disease and 8.15 (95% CI 3.59-18.5) for lung abscess or bronchiectasis. The aORs were 4.12 (95% CI 3.37-5.04) for solid cancer; 8.77 (95% CI 5.66-13.6) for hematological cancer; 12.0 (95% CI 6.13-23.7) for human immunodeficiency virus; and 5.71 (95% CI 4.22-7.75) for immunomodulating treatments. Population-attributable fractions showed were substantial contributors to the occurrence of brain abscess neurosurgery (12%); solid cancer (11%); ear, nose, and throat infections (7%); and immunomodulating treatments (5%).

CONCLUSIONS

Important risk factors included neurosurgery; cancer; ear, nose, and throat infections; and immunomodulating treatments.

Hemorrhagic Pseudocyst: A Rare Cerebral Mass Lesion Causing Death. A Case Report and Brief Review of Literature

ABSTRACT

Mass lesions in the brain encompass a wide range neoplastic and nonneoplastic entities. These can present as a diagnostic pitfall, with nonspecific, overlapping symptoms and similar appearances on radiology. They may cause death through varied mechanisms, either specific to the underlying pathophysiology or due to the space-occupying effect of the lesion. We report a case of fatal hemorrhagic cerebral pseudocyst, a rare mass lesion, associated with a cerebral varix, causing death in a morbidly obese individual. To the best of our knowledge, there is no previous documentation in the postmortem literature of this entity as a cause of death. This case aims to document this rare entity in the differential diagnosis of a tumor-like lesion in the brain, highlight the clinical difficulty in its assessment, and demonstrate an uncommon mechanism of death, of a mass lesion acting as a focus causing seizures, with resulting hypoxia due to effects of morbid obesity and heart failure.

Clinical outcomes of different treatments and risk factors in patients with otogenic brain abscess, a real-world evidence-based retrospective study

BACKGROUND

Otogenic Brain Abscess (OBA) is a life-threatening complication secondary to otitis media, but its appropriate management remains controversial.

OBJECTIVES

To understand the demographic characteristics, management, and variables that affect the outcomes of patients with OBA based on our experiences over 11 years.

MATERIAL AND METHODS

Clinical data were collected for 41 patients. Prognostic factors associated with mortality were assessed, and clinical outcomes compared among groups receiving different treatments.

RESULTS

Among the 41 patients, 19.6% did not undergo surgery, 39.0% were treated with two-stage surgery (otological surgery and neurosurgery) and 41.4% were treated with single-stage surgery (otological surgery or neurosurgery). Overall mortality rate was 32.5%, and mortality was significantly higher in patients with invasion of the petrous apex (odds ratio [OR]: 7.81, 95% confidence interval [95% CI]: 1.26-48.36), and lower in those with appropriate surgical management (single otological surgery, OR: 0.07, 95% CI: 0-0.97; single neurosurgery, OR: 0.13, 95% CI: 0.02-1.0; two-stage surgery, OR: 0.08, 95% CI: 0.01-0.64) or a higher Glasgow Coma Scale (GCS) score at admission (OR: 0.64, 95% CI: 0.44-0.93).

CONCLUSIONS AND SIGNIFICANCE

Data on invasiveness and pre-surgery GCS greatly aid in predicting the prognosis of OBA patients. Early evaluation will facilitate decision-making by physicians treating OBA patients.

Subdural Empyema by Enterobacter cloacae: Case Report

Infections of the central nervous system are a medical emergency, potentially lethal and associated with increased morbidity and mortality. We present the case of a male with risk factors and clinical deterioration, in which the brain computed tomography scan showed a subdural collection following a head injury, which underwent surgical evacuation revealing a subdural empyema. The culture of the subdural collection yielded a positive result to Enterobacter cloacae.

What you need to know about brain abscesses

A brain abscess is a focal accumulation of pus in the brain parenchyma arising from direct inoculation, contiguous spread from local anatomical structures or haematogenous seeding from a remote source of infection. It can result in significant morbidity and mortality, making early diagnosis and treatment vital. Only one fifth of patients present with the classic triad of headache, fever and focal neurological symptoms. More commonly patients show signs and symptoms of raised intracranial pressure alone, such as confusion or reduced conscious level, headache, nausea and vomiting, which can be a presentation of many intracranial pathologies. Distinguishing an abscess from other pathologies such as meningitis and tumours is crucial, as clinically these can present in similar ways, but their management and outcomes are very different. Diffusion-weighted magnetic resonance imaging brain scans can help localise the lesion and differentiate ring-enhancing lesions caused by a brain abscess from malignant tumours. Cerebral abscesses are considered a neurosurgical emergency; early stabilisation, diagnosis and management in a neurosurgical centre is important in reducing morbidity and mortality.

Microbial aetiology of brain abscess in a UK cohort: Prominent role of Streptococcus intermedius

BACKGROUND

Brain abscess is an uncommon condition, but carries high mortality. Current treatment guidelines are based on limited data. Surveillance of clinical, radiological and microbiology data is important to inform patient stratification, interventions, and antimicrobial stewardship.

METHODS

We undertook a retrospective, observational study of patients with brain abscess, based on hospital coding, in a UK tertiary referral teaching hospital. We reviewed imaging data, laboratory microbiology, and antibiotic prescriptions.

RESULTS

Over a 47 month period, we identified 47 adults with bacterial brain abscess (77% male, median age 47 years). Most of the abscesses were solitary frontal or parietal lesions. A microbiological diagnosis was secured in 39/47 (83%) of cases, among which the majority were of the Streptococcus milleri group (27/39; 69%), with a predominance of Streptococcus intermedius (19/27; 70%). Patients received a median of 6 weeks of intravenous antibiotics (most commonly ceftriaxone), with variable oral follow-on regimens. Ten patients (21%) died, up to 146 days after diagnosis. Mortality was significantly associated with increasing age, multiple abscesses, immunosuppression and the presence of an underlying cardiac anomaly.

CONCLUSION

Our data suggest that there has been a shift away from staphylococcal brain abscesses, towards S. intermedius as a dominant pathogen. In our setting, empiric current first line therapy with ceftriaxone remains appropriate on microbiological grounds and narrower spectrum therapy may sometimes be justified. Mortality of this condition remains high among patients with comorbidity. Prospective studies are required to inform optimum dose, route and duration of antimicrobial therapy.

Intracranial abscess from facial cellulitis

Cellulitis, one of most common diseases of everyday life, is often overlooked for its significance. Although cellulitis does not cause or lead to serious problems usually, its possibility to cause life-threatening problem should be known. In present case, a patient who had received acupuncture treatment a week earlier presented to the clinic with symptoms of facial cellulitis. The disease resolved within few weeks under empirical antibiotic treatment but recurred after 3 months. Under close history review of the patient, we found out that the patient had received craniectomy 20 years ago. The patient had blunt headache with no other neurological symptoms that could suspect cranial infection, but considering the risk originating from the patient’s surgical history, brain computed tomography (CT) was taken. CT images revealed abscess formation in the subgaleal and epidural spaces. Craniotomy with abscess evacuation was done promptly. With additional antibiotic treatment postoperatively, the disease resolved, and the 1-month postoperative follow-up brain CT showed no signs of abscess formation.