Consensus document on controversial issues for the treatment of infections of the central nervous system: bacterial brain abscesses. Int J Infect Dis. 2010;14 Suppl 4:S79-S92. [PMID: 20846891 DOI: 10.1016/j.ijid.2010.05.010]

Listeria brain abscess: a therapeutically challenging rare presentation of listeriosis

We report a very rare case of Listeria multiple brain abscesses manifested as delirium, which represented diagnostic and therapeutic challenges overcome only by the close cooperation between Infectious Diseases and Neuroradiology, without which a satisfactory outcome would not be achieved.An elderly man presented with confusion and drowsiness with a background of type-II diabetes mellitus. Although computed tomography of the brain only showed frontal lobe oedema, contrast magnetic resonance (MR) imaging showed numerous irregular rim-enhancing lesions containing central diffusion restriction, suggesting multiple pyogenic cerebral abscesses of unclear aetiology. Thereafter, Listeria monocytogenes was isolated from blood cultures, suggesting this as the causative organism. Deemed unsuitable for neurosurgical drainage, the patient received medical management with a protracted course of antibiotics. This case was extremely challenging, due to 1) the impossibility of source control, 2) the small number of effective antibiotics available to treat this condition, and 3) the inevitable antibiotic side-effects, derived from long-term exposure. A successful outcome was only possible thanks to strict close multidisciplinary follow up, requiring frequent MR imaging and a judicious antibiotic choice, including monitoring of their side-effects. Due to the rarity of this condition, there is lack of guidance on its management, hence the importance of multidisciplinary involvement with very close imaging and antibiotic monitoring.

Clinical characteristics and outcomes of children with non-sinogenic Brain infections

BACKGROUND

Central Nervous System (CNS) suppurative infections are serious but rare conditions in the paediatric population. Data on long-term neurocognitive and quality of life outcomes in children recovering from these infections are lacking.

METHODS

A retrospective cohort review of children <16 years with non-sinogenic infections undergoing neurosurgery was conducted. Data for patients admitted to Children's Health Ireland at Temple St between 2008-2021 were analysed for clinical and microbiological profiles. Follow-up reviews evaluating neurological and academic sequelae and quality of life were performed. Categorical variables were analysed for unfavourable outcome with a p < 0.05 significance value.

RESULTS

Forty patients were included with a mean age of 4.5 years and equal gender distribution. Fever (68%) and vomiting (58%) were the most common presenting complaints. Only fourteen (35%) patients presented with the classic triad of fever, headache, and focal neurological deficit. Meningitis/Encephalitis was the most common cause of suppurative infection (40%). Predisposing factors included congenital heart disease (18%), prematurity (15%) and immunocompromised status (10%). More patients received an initial Burr hole aspiration (73%) than Craniotomy (27%). The re-operation rate was higher in the craniotomy group (45%) compared to the burr hole group (34%), but this was not statistically significant (p = 0.522). Four patients died (10%) including two intra-hospital deaths (5%). Male gender (p = 0.047) and multiple abscesses (p = 0.041) were associated with unfavourable outcome at discharge. Mobility impairment was the most affected determinant of quality of life.

CONCLUSION

CNS suppurative infections are associated with long-term neurocognitive sequelae in children. Multiple abscesses and male gender are associated with unfavourable GOS on discharge. Children are still left with mobility impairment (25%), personality changes (23%) and intellectual disability (18%) at an average of 5 years. Long-term follow up with multidisciplinary input is required. Further research should focus on evaluating long-term HRQoL in children.

A Canadian National Survey of the Neurosurgical Management of Intracranial Abscesses

OBJECTIVE

Intracerebral abscess is a life-threatening condition for which there are no current, widely accepted neurosurgical management guidelines. The purpose of this study was to investigate Canadian practice patterns for the medical and surgical management of primary, recurrent, and multiple intracerebral abscesses.

METHODS

A self-administered, cross-sectional, electronic survey was distributed to active staff and resident members of the Canadian Neurosurgical Society and Canadian Neurosurgery Research Collaborative. Responses between subgroups were analyzed using the Chi-square test.

RESULTS

In total, 101 respondents (57.7%) completed the survey. The majority (60.0%) were staff neurosurgeons working in an academic, adult care setting (80%). We identified a consensus that abscesses >2.5 cm in diameter should be considered for surgical intervention. The majority of respondents were in favor of excising an intracerebral abscess over performing aspiration if located superficially in non-eloquent cortex (60.4%), located in the posterior fossa (65.4%), or causing mass effect leading to herniation (75.3%). The majority of respondents were in favor of reoperation for recurrent abscesses if measuring greater than 2.5 cm, associated with progressive neurological deterioration, the index operation was an aspiration and did not include resection of the abscess capsule, and if the recurrence occurred despite prior surgery combined with maximal antibiotic therapy. There was no consensus on the use of topical intraoperative antibiotics.

CONCLUSION

This survey demonstrated heterogeneity in the medical and surgical management of primary, recurrent, and multiple brain abscesses among Canadian neurosurgery attending staff and residents.

Clinical Features and Diagnosis of Intramedullary Spinal Cord Abscess in Adults: A Systematic Review

BACKGROUND AND OBJECTIVES

Intramedullary spinal cord abscess (ISCA) was described 200 years ago but remains poorly understood and is often mistaken for immune-mediated or neoplastic processes. We present a systematic review of ISCA in adults, describing the clinical presentation, diagnostic features, treatment strategies, and outcomes.

METHODS

Database searches for intramedullary abscess were performed on April 15, 2019, and repeated on February 9, 2022, using PubMed and EMBASE with 2 unpublished cases also included. Publications were independently reviewed for inclusion by 2 authors followed by adjudication. Data were abstracted using an online form and then analyzed for predictors of disability.

RESULTS

A total of 202 cases were included (median age 45 years [interquartile range 31-58]; 70% male). Thirty-one percent of those affected had no identified predisposing condition. The most common symptom was weakness (97%), and the median symptom duration before presentation was 10 days (interquartile range 5-42). An MRI showed restricted diffusion in 100% of 8 cases where performed and enhancement in 99% of 153 cases where performed. The most common organisms were Mycobacterium tuberculosis (29%), Streptococcus sp. (13%), and Staphylococcus sp. (10%). All patients received antimicrobial therapy; surgical drainage was performed in 65%. At follow-up (median 6 months), 12% had died, 69% were ambulatory, and 77% had improved compared with clinical nadir. Of those who underwent operative intervention, surgery within 24 hours of diagnosis was associated with an increased likelihood of being ambulatory at follow-up compared with surgery after 24 hours (odds ratio 4.44; 95% CI 1.26-15.61; p = 0.020).

DISCUSSION

ISCA is important to consider in any patient presenting with acute-to-subacute, progressive myelopathy. Immunocompromise and typical signs of infection (e.g., fever) are often absent. Diffusion restriction and gadolinium enhancement on MRI seem to be sensitive. Antimicrobial therapy with surgical drainage is the most common therapeutic approach, but morbidity remains substantial. If performed, urgent surgery may be more beneficial.

Cerebral abscess due to Listeria monocytogenes infection in silent diabetes mellitus: Case presentation, treatment and patient outcome

Introduction

Invasive listeriosis most often presents as bacteremia or neurolisteriosis. Cerebral infection mostly manifests as meningitis or meningoencephalitis, but cerebral abscesses are a rare manifestation.

Case presentation

We present the rare case of a 51-year old patient with progressive right sided hemiparesis caused by a cerebral abscess due to Listeria monocytogenes infection. The initially suspected cerebral ischemia or bleeding was ruled out. Magnetic resonance imaging led to the suspected diagnosis of an angiocentric lymphoma. An open cerebral biopsy revealed an intracranial abscess formation. After abscess evacuation and identification of Listeria monocytogenes, anti-infective treatment with ampicillin and gentamicin was started. After repeated cerebral imaging with signs of ongoing tissue inflammation after 6 weeks we chose to prolong the therapy with oral amoxicillin until resolution of signs of intracerebral inflammation after 12 weeks, documented by repeated cerebral magnetic resonance imaging. During hospitalization, the patient was diagnosed with diabetes mellitus type II and treatment was initiated. The patient was discharged without any persistent neurologic deficits.

Discussion

For the treatment of bacterial brain abscesses, 4-6 weeks of intravenous antimicrobial treatment after surgical drainage are recommended. However, first line therapy of invasive cerebral listeriosis is not well established. We decided to use a combined treatment using ampicillin and gentamicin, followed by prolonged oral treatment due to ongoing tissue inflammation.

Conclusion

No evidence-based treatment recommendations are available for brain abscess caused by Listeria monocytogenes. We report a case with favorable outcome after anti-infective ampicillin- and gentamicin-based therapy. Systematic assessment of treatment would be desirable.

Retrospective review of the epidemiology, microbiology, management and outcomes of intra-cranial abscesses at a neurosurgical tertiary referral centre, 2018-2020

BACKGROUND

Intracranial abscesses are rare but serious, and are associated with significant morbidity and mortality. Due to both the rarity and severity of these infections, well-controlled trials have not been reported in the literature, and optimal management is a matter for expert opinion. Advances in surgical management have improved outcomes and increased rates of microbiological diagnosis. However, the approach to antimicrobial chemotherapy varies considerably, including the choice of antibiotic, the duration of treatment, and the timing of oral switch.

METHODS

We conducted a retrospective review of 43 cases of intracranial abscesses from a large, tertiary neurosurgical centre in London, UK, between 2018 and 2020, including 29 primary intra-parenchymal abscesses, 11 subdural abscesses and 3 extradural abscesses.

RESULTS

The majority of cases had surgical intervention; 6/43 (14%) required repeat intervention (all intra-parenchymal abscesses). A microbiological diagnosis was made in 83% of cases. Intravenous antibiotics were given for a median of 33 days (IQR 23-44 days), with a variable duration of oral follow-on antibiotics. Total duration of antibiotic treatment ranged from 0 to 467 days. Only three patients from our cohort are known to have died.

CONCLUSION

Shorter courses of intravenous antibiotics for brain abscesses were not associated with increased mortality. In the absence of well-controlled trials, a national registry of intracranial abscesses would provide invaluable data to inform optimal treatment.

Surgical management of an abscess of the insula

Background

Mass lesions within the insular are diagnostically and surgically challenging due to the numerous critical cortical, subcortical, and vascular structures surrounding the region. Two main surgical techniques - the transsylvian approach and the transcortical approach - provide access to the insular cortex. Of the range of pathologies encountered, abscesses in the insula are surprisingly rare.

Case Description

A 34-year-old patient was admitted for surgical resection of a suspected high-grade glioma in the insula of the dominant hemisphere. A rapid clinical decline prompted emergent neurosurgical intervention using a transsylvian approach. Surprisingly, abundant purulent material was encountered on entering the insular fossa. Pathological analysis confirmed an insular abscess, although a source of infection could not be identified. The patient required a second evacuation for reaccumulation of the abscess and adjuvant corticosteroids for extensive cerebral edema.

Conclusion

An abscess located in the insular cortex is an incredibly rare occurrence. Surgical management using the transsylvian approach is one option to approach this region. Familiarity with this approach is thus extremely beneficial in situations requiring emergent access to the dominant insula when awake mapping is not feasible. In addition, treatment of abscesses with adjuvant corticosteroids is indicated when extensive, life-threatening cerebral edema is present.

Aspiration Surgery with Appropriate Antibiotic Treatment Yields Favorable Outcomes for Bacterial Brain Abscess

BACKGROUND

Even in the era of advanced medical treatment, brain abscess still has a high mortality rate. At our institution, brain abscess has been treated mainly using stereotactic or echo-guided aspiration followed by relatively long-term antibiotic treatment, achieving favorable outcomes. To evaluate the efficacy of our strategy involving less-invasive aspiration surgery and long-term selective antibiotic administration for brain abscess, a single-institution series of cases was investigated.

METHODS

We retrospectively reviewed and analyzed the medical records of 25 cases of brain abscess treated at Saitama Medical University Hospital between 2008 and 2021. The patients comprised 16 men and 9 women aged between 39 and 85 years (median 62 years). Neurosurgical intervention was performed for 23 (92.0%) of the patients and the remaining 2 received antibiotics alone.

RESULTS

Among the neurosurgery patients, 22 (95.7%) underwent echo-guided or stereotactic aspiration, and only 1 underwent craniotomy. Anaerobic bacteria were detected in 11 patients. In the surgical and conservative groups, the median duration of antibiotic treatment was 16 weeks and 23 weeks, respectively. Since 2014 when metronidazole first became available, it has replaced meropenem to cover anaerobic bacteria. The overall mortality rate was 4.0% and a favorable outcome (Glasgow Outcome Scale 4 or 5) was achieved in 76% of the patients. There was no surgical mortality or morbidity.

CONCLUSIONS

Most patients underwent aspiration surgery and achieved favorable outcomes. Along with antibiotic treatment for a sufficiently long period to cover anaerobes, this approach can be expected to yield good results.

Brain Abscess with Pyogenic Ventriculitis

The authors present the case of a 57-year-old male with a large polymicrobial brain abscess complicated by eruption into the intraventricular space. He was treated with parenteral ampicillin, cefepime, and metronidazole and adjuvant intraventricular vancomycin/gentamicin as well as surgical debridement. The authors discuss the diagnosis, treatment, and prognosis of brain abscesses, with a focus on prior cases with pyogenic ventriculitis and those treated with intraventricular antimicrobials.

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.

Case report: Cryptogenic giant brain abscess caused by Providencia rettgeri mimicking stroke and tumor in a patient with impaired immunity

The highly lethal cryptogenic brain abscess can be easily misdiagnosed. However, cryptogenic brain abscess caused by Providencia rettgeri is rarely reported. We present the case of a cryptogenic Providencia rettgeri brain abscess and analyze the clinical manifestations, imaging findings, treatment, and outcome to improve the level of awareness, aid in accurate diagnosis, and highlight effective clinical management. A 39-year-old man was admitted to the hospital after experiencing acute speech and consciousness disorder for 1 day. The patient had a medical history of nephrotic syndrome and membranous nephropathy requiring immunosuppressant therapy. Magnetic resonance imaging revealed giant, space-occupying lesions involving the brain stem, basal ganglia, and temporal-parietal lobes without typical ring enhancement, mimicking a tumor. Initial antibiotic treatment was ineffective. Afterward, pathogen detection in cerebrospinal fluid using metagenomic next-generation sequencing revealed Providencia rettgeri. Intravenous maximum-dose ampicillin was administered for 5 weeks, and the patient's symptoms resolved. Cryptogenic Providencia rettgeri brain abscess typically occurs in patients with impaired immunity. Our patient exhibited a sudden onset with non-typical neuroimaging findings, requiring differentiation of the lesion from stroke and brain tumor. Metagenomic next-generation sequencing was important in identifying the pathogen. Rapid diagnosis and appropriate use of antibiotics were key to obtaining a favorable outcome.

The utility of 16S rRNA gene sequencing on intraoperative specimens from intracranial infections: an 8-year study in a regional UK neurosurgical unit

Background: Optimal management of intracranial infections relies on microbiological diagnosis and antimicrobial choice, but conventional culture-based testing is limited by pathogen viability and pre-sampling antimicrobial exposure. Broad-range 16S rRNA gene sequencing has been reported in the management of culture-negative infections but its utility in intracranial infection is not well-described. We studied the efficacy of 16S rRNA gene sequencing to inform microbiological diagnosis and antimicrobial choice in intracranial infections.Methods: This was a retrospective study of all intraoperative neurosurgical specimens sent for 16S rRNA gene sequencing over an 8-year period at a regional neurosurgical centre in the UK. Specimen selection was performed using multidisciplinary approach, combining neurosurgical and infection specialist discussion.Results: Twenty-five intraoperative specimens taken during neurosurgery from 24 patients were included in the study period. The most common reason for referral was pre-sampling antimicrobial exposure (68%). Bacterial rDNA was detected in 60% of specimens. 16S rRNA gene sequencing contributed to microbiological diagnosis in 15 patients and informed antimicrobial management in 10 of 24 patients with intracranial infection. These included targeted antibiotics after detection of a clinically-significant pathogen that had not been identified through other microbiological testing (3 cases), detection of commensal organisms in neurosurgical infection which justified continued broad cover (2 cases) and negative results from intracranial lesions with low clinical suspicion of bacterial infection which justified avoidance or cessation of antibiotics (5 cases).Conclusion: Overall, 16S rRNA gene sequencing represented an incremental improvement in diagnostic testing and was most appropriately used to complement, rather than replace, conventional culture-based testing for intracranial infection.

Continuous Antibiotic Administration Using IRRAflow® Catheter for Treatment of Intracranial Abscess

Intracranial abscesses are rare lesions with an incidence of approximately 4 per 1 million people. The optimal surgical management of these lesions is still unclear. We present the case of a patient who was discovered to have an intracranial abscess after presenting with right-sided weakness. He was treated via a combination of open craniotomy and continuous antibiotic irrigation using an IRRAflow® catheter (IRRAS, Stockholm, Sweden). Use of the IRRAflow® in this fashion has not yet been described in the literature. This novel approach appears to be safe and resulted in continued decrease in the abscess burden following surgical drainage.

Lemierre's syndrome caused by Fusobacterium necrophorum complicated with multiple brain abscesses-A case report, literature review, and suggested management

We present an unusual case of Lemierre´s syndrome complicated by multiple brain abscesses, a literature review and suggested management. A young man with multiple brain abscesses deteriorated despite two weeks of directed antibiotics. A multidisciplinary approach was successful. Hyperbaric oxygen treatment (HBOT) should be considered in refractory or severe cases.

Treatment of Nocardial Brain Abscess in a Patient With Systemic Lupus Erythematosus and Idiopathic Thrombocytopenic Purpura: Case Report and a Review of the Literature

Brain abscesses due to Nocardia species account for 1-2% of all cerebral abscesses, often in immunosuppressed individuals, with a mortality three times higher than other cerebral abscesses. Early diagnosis and management are vital for good outcomes. We report a case of a right frontal Nocardia brain abscess in an immunosuppressed 38-year-old female. She presented with headaches, confusion, memory deficits, and personality change. She remained systemically well, with normal inflammatory markers. She underwent two open surgical drainages, with excision of the abscess wall. She made an excellent recovery with minimal edema and no contrast enhancement on imaging at eight weeks postoperatively. Management of Nocardia brain abscess includes a prompt diagnosis with direct microscopic examination and initiation of correct antibiotic therapy for good outcomes. We recommend open surgical resection, including excision of the abscess wall, followed by long-term antimicrobial therapy, to enhance the rate of recovery.

Hypertensive emergency and seizures during haemodialysis

Intracranial abscesses are uncommon, serious and life-threatening infections. A brain abscess is caused by inflammation and collection of infected material, coming from local or remote infectious sources. Patients with chronic kidney disease on dialysis are prone to invasive bacterial infections like methicillin-resistant Staphylococcus aureus (MRSA) especially in the presence of central venous catheters or arteriovenous grafts. However, intracranial abscess formation due to MRSA is rare. Here, we present a case of MRSA brain abscess with an atypical clinical presentation in the absence of traditional risk factors.Intracranial abscesses are uncommon, serious, and life-threatening infections. A Brain abscess is caused by inflammation and collection of infected material, coming from local or remote infectious sources. Patients with chronic kidney disease on dialysis are prone to invasive bacterial infections like methicillin-resistant staphylococcus aureus (MRSA) especially in the presence of central venous catheters or arterio-venous grafts. However intracranial abscess formation due to MRSA is rare. Here we present a case of MRSA brain abscess with an atypical clinical presentation in the absence of traditional risk factors. A 46-year-old male with chronic kidney disease (CKD) secondary to chronic glomerulonephritis, on haemodialysis for 4 years through a left brachio-cephalic AVF developed an episode of generalised tonic-clonic seizures lasting 2 min during his scheduled dialysis session. He reported no complaints before entry to the dialysis. On clinical examination, he was drowsy with the absence of any focal motor deficits. His blood pressure was recorded to be 200/120 mm Hg. He was managed in the intensive care unit with mechanical ventilation, intravenous nitroglycerine for blood pressure control, levetiracetam for seizures and empirical vancomycin. Radiological evaluation showed a brain abscess in the midline involving bosth basi-frontal lobes. After medical optimization, the abscess was drained surgically, and the pus cultured. As culture grew Methicillin Resistant Staphylococcus aureus, he was treated with intravenous vancomycin for 6 weeks. On follow up, the abscess had resolved and the patient recovered without any neurological deficits.

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.

Conservative management of a large brain abscess in a child with severe manifestations: A case report from Syria

Otogenic brain abscesses are rare but usually life-threatening conditions particularly in developing countries. Our patient attended to the emergency department with extremely serious manifestations due to a large brain abscess. The borderline dimensions of the abscess (2.4 cm) with (GCS <12) as well as the lack of surgical capabilities were the factors that addressed to treat her with the available medication only. Fortunately, 2-year follow-up did not show any recurrence. This case sheds a light on unusual management of large abscesses in imperfect circumstances, which makes it high educational value.

Giant Actinomyces brain abscess in an immunocompetent child: A management strategy

BACKGROUND

Intraparenchymal brain abscess is a collection of microbes caused by inoculation through direct extension or hematogenous spread. Although rare, intraparenchymal abscesses are potentially fatal and can be detected when patients are symptomatic due to local mass effect on adjacent neural tissue. Brain abscess treatment includes medical management with appropriate antibiotics alone or medical management in combination with surgical debridement. Treatment strategies depend on the size and location of disease, as well as the virulence of the microorganism. Similar to medical management strategies, surgical strategies among providers are not uniform, with variation in approaches from complete extirpation of the abscess, including the abscess wall, to minimally invasive stereotactic needle aspiration. In particular, for children, there are no guidelines for therapy.

CASE DESCRIPTION

We report a case of giant Actinomycosis right frontal brain abscess in an immunocompetent child without risk factors. A review of the literature for the treatment of brain abscess caused very rarely by Actinomyces in children is performed.

CONCLUSION

Successful treatment of brain access depends on organism and location. The even more uncommon giant intraparenchymal abscesses can be managed with minimal access and prolonged antibiosis, especially when slow-growing organisms are identified. Long-term follow-up should be employed to mitigate missed late failures.

Switch from parenteral to oral antibiotics for brain abscesses: a retrospective cohort study of 109 patients

OBJECTIVES

Brain abscess is one of the most serious diseases of the CNS and is associated with high morbidity and mortality. With regard to the lack of data supporting an optimal therapeutic strategy, this study aimed to explore the prognostic factors of brain abscess, putting emphasis on the impact of therapeutic decisions.

METHODS

We retrospectively included patients hospitalized for brain abscess during a period of 13 years. Comorbidities (Charlson scale), clinical presentation, microbiology culture, radiological features and therapeutic management were collected. Glasgow Outcome Scale (GOS) at 3 months and length of hospital stay were, respectively, the main and the secondary outcomes. Logistic regression was used to determine factors associated with outcome independently.

RESULTS

Initial Glasgow Coma Scale (GCS) ≤14 and comorbidities (Charlson scale ≥2) were associated with poor neurological outcome while oral antibiotic switch was associated with better neurological outcome. Oral switch did not appear to be associated with an unfavourable evolution in the subset of patients without initial neurological severity (GCS >14) on admission. Duration of IV regimen and time to oral switch were associated with the length of inpatient stay.

CONCLUSIONS

This study confirms the role of GCS and comorbidities as prognostic factors and presents reassuring data regarding the safety of oral switch for the antibiotic treatment of brain abscesses. Oral switch could prevent catheter-induced iatrogenic complications and allow a higher quality of life for patients.

Neuroinfectious Disease Emergencies

Neuroinfectious diseases can affect immunocompetent and immunosuppressed individuals and cause a variety of emergencies including meningitis, encephalitis, and abscess. Neurologic infections are frequently complicated by secondary injuries that also present emergently such as cerebrovascular disease, acute obstructive hydrocephalus, and seizure. In most cases, timely recognition and early treatment of infection can improve the morbidity and mortality of infectious neurologic emergencies.

Brain Abscess Apparent Diffusion Coefficient is Associated With Microbial Culture Yields

BACKGROUND

Obtaining pus for microbial cultures is one of the surgical aims in patients with brain abscess. Predictors of microbial yields are necessary as they help in treatment planning.

PURPOSE

To investigate the relationship between microbial culture yields of brain abscesses and their apparent diffusion coefficient (ADC) values and clinical characteristics.

STUDY TYPE

Retrospective.

SUBJECTS

Eighty-four patients diagnosed with brain abscess by surgery and histopathology (59 with positive abscess cultures).

FIELD STRENGTH/SEQUENCE

Diffusion-weighted, T2-weigthed, and contrast-enhanced T1-weighted imaging at 1.5 T and 3 T.

ASSESSMENT

Contrast-enhanced T1-weighted images were co-registered to ADC maps. Three neuroradiologists determined abscess imaging characteristics (distribution, location, and ventricular rupture), and two measured abscess volumes and ADC values. Clinical characteristics collected included sex, age, fever, underlying diseases, infection sources, white blood cell count, percentage of segmented neutrophils, C-reactive protein level, regimen and duration of empirical antibiotics, and types of surgery.

STATISTICAL TESTS

Interobserver differences were assessed with Fleiss kappa and intraclass correlation coefficients. The differences in clinical and imaging factors between the positive and negative culture groups were compared with Chi-square analysis or Student's t test. All factors were subjected to multivariable logistic regression analysis to assess their associations with microbial culture yields, and factors with statistical significance were evaluated with receiver operating characteristic curve analysis to assess their diagnostic performance in discriminating the two groups.

RESULTS

Mean ADC (×10^-6  mm² /s) of culture-negative abscesses (841 ± 173) was significantly higher (P < 0.05) than that of culture-positive abscesses (536 ± 90). On multivariable analysis, mean ADC was the only significant factor (P < 0.05) related to culture yields. With 660 as the cutoff value, the sensitivity, specificity, and accuracy of ADC for discriminating culture yields were 93.2%, 88.0%, and 91.7%, respectively.

DATA CONCLUSION

ADC could be used to discriminate between culture-positive and culture-negative abscesses.

EVIDENCE LEVEL

4 TECHNICAL EFFICACY: Stage 2.

A rare case of voluminous brain abscess due to Actinomyces meyeri and Aggregatibacter aphrophilus: is there any evidence for a prolonged antibiotic oral relay?

We present the case of a patient with a voluminous cerebral abscess caused by Aggregatibacter aphrophilus and Actinomyces meyeri occurring a week post dental scaling. Both these bacteria are rarely involved in brain abscesses, and so far, cases of cerebral actinomyces have mostly been treated surgically and with intravenous (IV) antibiotics for 3-4 months, then put on oral antibiotic therapy with penicillin or amoxicillin for a further 3-12 months. Our patient underwent drainage through craniotomy and was subsequently put on intravenous ceftriaxone for 3 months accompanied by brain imaging control at the end of this period which showed complete regression of the abscess. Following parenteral treatment, no oral antibiotics were given since pharmacokinetic properties do not allow to attain high tissue concentration in the brain. This treatment gave excellent results.

Management of infective complications of otitis media in resource-constrained settings

PURPOSE OF REVIEW

Complications of otitis media are a cause of significant morbidity and mortality, compounded in resource-constrained settings in which human and physical resources to manage disease are suboptimal. Here, we examine the current best evidence to devise a protocol for management, in particular exploring the opportunity for conservative or nonspecialist management.

RECENT FINDINGS

Reviews of the literature suggest that intratemporal and extracranial infections can be managed with antibiotics in the first instance, with aspiration or incision and drainage of abscess. Failure to respond necessitates mastoidectomy, which need not be extensive, and can be performed with hammer and gouge. Suspected or possible intracranial extension requires referral for computed tomography (CT) imaging. Intracranial infection can in some instances be managed with antibiotics, but large or persistent intracranial abscess, or the presence of cholesteatoma requires management in a centre for specialist surgery.

SUMMARY

Many complications of otitis media could be managed by nonspecialists in appropriately equipped local or regional health facilities, and supported by appropriate training. However, regional centres with CT imaging and specialist surgery are required for assessment and treatment of cases that are suspected of having complex or advanced disease, or that fail to respond to initial treatment. Those involved in planning healthcare provision should look to develop infrastructure to support such management.

Klebsiella brain abscess in an immunocompetent patient: a case report

Background

Klebsiella pneumoniae brain abscesses are a rare entity and typically present in immunocompromised patients. We present a case of an overall healthy patient who developed a Klebsiella pneumoniae brain abscess in the absence of liver pathology.

Case presentation

A 46-year-old Vietnamese man with past medical history significant for hypertension presented to the hospital with acute on chronic worsening of altered mental status, personality changes, and gait dysfunction. Initial vitals revealed temperature of 37.1 °C, heart rate 87 beats/minute, blood pressure 150/87 mmHg, respiratory rate 18/minute, and oxygen saturation 99% on room air. Physical exam was notable for altered mental status, Glasgow Coma Scale (GCS) score of 14, and right lower facial droop. Cardiopulmonary exam was within normal limits. Head computed tomography (CT) showed a left frontotemporal mass, with subsequent brain magnetic resonance imaging (MRI) revealing a ring-enhancing lesion concerning for a brain abscess. The abscess was urgently drained; however, there was intraoperative spillage into the ventricles. Intraoperative cultures grew Klebsiella pneumoniae, and the patient was maintained on appropriate antibiotics. He developed worsening mental status, septic shock, and cerebral edema requiring decompressive left hemicraniectomy. Computed tomography of the abdomen and pelvis revealed no hepatic lesions. The patient did not improve, and the family elected for comfort measures.

Conclusion

High mortality is associated with Klebsiella pneumoniae (as opposed to Klebsiella oxytoca) brain abscesses, especially in the setting of intraventricular spread. This case illustrates the need for early detection, and an aggressive medical and surgical treatment approach is required for a potential favorable outcome.

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.

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.

Fever and temporal headache in a 70-year-old male with presumed large vessels vasculitis

Background:

Listeria monocytogenes is an opportunistic pathogen that causes severe infections of the Central Nervous System, such as meningitis or meningoencephalitis, and brain abscesses. Abscesses account for approximately 1–10% of CNS listerial infections and are observed in 1% of all listerial infections.

Methods:

We describe a case of 70-year-old male patient who had several admissions in different hospitals over the last 8 weeks.

Results:

He suffered from intermittent fever for over a month, recurrent episodes of headaches, disorientation and other neurological symptoms. His condition was misdiagnosed as giant cell arteritis and initially the patient was started on corticosteroids. MRI of the brain revealed the presence of multiple brain abscesses and the cerebrospinal fluid study confirmed the presence of Listeria Monocytogenes. The patient was started on ampicillin and he completed a 6 weeks’ course of treatment.

Conclusions:

This case emphasizes the need to include rare pathogens in the differential diagnosis when possible CNS infections are involved, as well as to show that in many cases some auto-immune diseases are overdiagnosed.

Facilitating heart transplantability in an end-stage heart failure patient with brain abscess and infected left ventricle assist device-A unique case report

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Therapeutic scope in a patient designated with no therapeutic option left.

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Strategy ineligible for heart transplantation for uncontrolled infection.

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Extraordinary case elucidating our unestablished treatment strategy.

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Finally after treatment patient was listed for heart transplantation.

Introduction

Heart transplantation is the desired therapy in end-stage heart failure (HF) and in patients with left-ventricular assist devices (LVAD) suffering from life-threatening complications on device. Comorbidities are frequent in end-stage HF and may refrain the patient from being listed for heart transplantation such as infections making surgery impossible.

Presentation of case

We report the first case of a patient with proven LVAD system infection who additionally suffers from a brain abscess that made listing for heart transplantation impossible, leaving this patient no apparent treatment option.

Conclusion

Our extraordinary treatment strategy finally resolved both the brain abscess and LVAD system infection through extensive conservative long-term treatment facilitating this patient to be finally listed for regular heart transplantation and sustained relieve of systemic infection.

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.

[Otogenic and rhinogenic intracranial complications: meningitis and brain abscess in adults]

The purpose of this study is to review etiology, diagnosis and management strategies of rhinogenic and otogenic meningitis and brain abscess in adults. Current diagnostic procedures, effective surgery and antibiotic treatment are discussed. The clinical case of diagnosis and successful treatment of the patient with rhinogenic meningitis and brain abscesses is presented.

Clinical features, microbiology, and management of pediatric brainstem abscess

PURPOSE

Brainstem abscess is a rare condition accounting for merely 1% of brain abscesses incidence in the pediatric population. This study aimed to present a single patient with a pontine abscess and review the literature to highlight clinical features, diagnosis, and management of brainstem abscess.

METHODS

The PubMed database was screened for English-language articles concerning pediatric brainstem abscess. We, therefore, identified 22 publications, which concisely depict 23 cases. Our study reports on the 24th pediatric patient diagnosed with that entity. All included reports were analyzed in terms of clinical presentation, diagnosis, management, and outcomes of described patients.

RESULTS

There was slight women predominance (15:9), with a mean age of occurrence 6.4 years, ranging from 7 months to 16 years. Pons was the most common location of brainstem abscess, occurring in 75% of patients. Clinically, they mostly presented with cranial nerves palsy (79.2%), hemiparesis (66.7%), and pyramidal signs (45.8%). The classic triad of symptoms, including fever, headache, and the focal neurologic deficit was present in 20.8% of patients. Positive pus cultures were obtained in 61.1%. Streptococci and Staphylococci were the most frequently identified pus microorganisms. Outcomes were satisfactory, with a 79.2% rate of general improvement.

CONCLUSIONS

Neurosurgical aspiration is a safe and beneficial therapeutic method. It should always be considered and should promptly be performed when the conservative treatment is not successful and clinical deterioration occurs. Prognosis in pediatric brainstem abscess is generally favorable. Most patients recover with minor neurologic deficits or improve completely.

Brain abscess in pediatric age: a review

OBJECTIVE

The purpose of the paper is to examine the current state of the art about epidemiology, diagnosis, and treatment of this infection.

METHODS

A review of the literature was performed through a PubMed search of original articles, case reports, and reviews using the key words "brain abscess," "cerebral abscess," "brain infection," "intracranial suppuration," "otogenic brain abscess," "otitis complications," and "sinusitis complications."

RESULTS

Pediatric brain abscess is a rare but serious infection, often involving patients with specific risk factors and burdened by a high risk of morbidity and mortality. Brain abscess incidence and mortality decreased over the years, thanks to improved antibiotic therapy, new neurosurgical techniques, and the wide spread of vaccinations. There are no guidelines for the adequate diagnostic-therapeutic pathway in the management of brain abscesses; therefore, conflicting data emerge from the literature. In the future, multicentric prospective studies should be performed in order to obtain stronger evidences about brain abscesses management. Over the next few years, changes in epidemiology could be observed because of risk factors changes.

Infective endocarditis and brain abscess secondary to Aggregatibacter aphrophilus

Aggregatibacter aphrophilus is a rare cause of infective endocarditis that was first described in 1940 by Khairat et al. and is now classified under the HACEK group of bacteria (Haemophilus spp., Aggregatibacter spp., Cardiobacterium hominis, Eikenella corrodens, and Kingella kingae). There is limited literature describing the extracardiac complications of infective endocarditis caused by this organism. We report a case of a 53-year-old male with no significant past medical history who developed acute infective endocarditis complicated by a brain abscess caused by A. aphrophilus. The patient underwent aspiration of the abscess and treated with a long course of intravenous antimicrobials. This case represents a rare complication of infective endocarditis caused by A. aphrophilus and to the best of our knowledge, is the second reported case in the literature describing such a complication in a previously healthy patient. Although neurological sequela is associated with higher mortality and may be the presenting symptom of infective endocarditis, it may also be clinically silent - only detected upon imaging.

Paediatric focal intracranial suppurative infection: a UK single-centre retrospective cohort study

Background

Paediatric focal intracranial suppurative infections are uncommon but cause significant mortality and morbidity. There are no uniform guidelines regarding antibiotic treatment. This study reviewed management in a tertiary healthcare centre in the United Kingdom and considers suggestions for empirical treatment.

Methods

A retrospective, single-centre cohort review of 95 children (< 18 years of age) with focal intracranial suppurative infection admitted between January 2001 and June 2016 in Newcastle upon Tyne, United Kingdom. Microbiological profiles and empirical antibiotic regimens were analysed for coverage, administration and duration of use. Mortality and neurological morbidity were reviewed. Data was analysed using t-tests, Mann-Whitney U tests, independent-samples median tests, and χ²-tests where appropriate. P-values < 0.05 were considered statistically significant.

Results

Estimated annual incidence was 8.79 per million. Age was bimodally distributed. Predisposing factors were identified in 90.5%, most commonly sinusitis (42.1%) and meningitis (23.2%). Sinusitis was associated with older children (p < 0.001) and meningitis with younger children (p < 0.001). The classic triad was present in 14.0%.

43.8% of 114 isolates were Streptococcus spp., most commonly Streptococcus milleri group organisms. Twelve patients cultured anaerobes.

Thirty one empirical antibiotic regimens were used, most often a third-generation cephalosporin plus metronidazole and amoxicillin (32.2%). 90.5% would have sufficient cover with a third generation cephalosporin plus metronidazole. 66.3% converted to oral antibiotics. Median total antibiotic treatment duration was 90 days (interquartile range, 60–115.50 days).

Mortality was 3.2, 38.5% had short-term and 24.2% long-term neurological sequelae.

Conclusions

Paediatric focal intracranial suppurative infection has a higher regional incidence than predicted from national estimates and still causes significant mortality and morbidity. We recommend a third-generation cephalosporin plus metronidazole as first-choice empirical treatment. In infants with negative anaerobic cultures metronidazole may be discontinued.

A Clinical Report of Two Cases of Cryptogenic Brain Abscess and a Relevant Literature Review

Brain abscess, a severe intracranial infectious disease, refers to the parenchyma abscess caused by local infection or remote spread. Recently, advancements in modern medicine, especially the wide application of antimicrobial drugs, have contributed to the gradual decrease in the prevalence of this disease. However, cases of cryptogenic brain abscess that feature an unknown origin and atypical symptoms are rising. In this retrospective study, we report and analyze two cases of cryptogenic brain abscess. The first patient was a 30-year-old healthy man who was admitted to our hospital due to 1 week of headache and 3 days of headache aggravation, accompanied by nausea and vomiting. Head MRI shows a circular space-occupying as well as apparently enhanced DWI signals were observed in the right parietal lobe, and the ring wall manifested an apparent increase in signal intensity after enhancement. The patient was diagnosed as a brain abscess before operation and given craniotomy. The postoperative pathology confirmed brain abscess and recovered well after surgery. The second patient was a 45-year-old healthy woman who was hospitalized in a local hospital due to symptoms of headache and right limb weakness for 1 week. Head MRI shows a circular space-occupying lesion in the left basal ganglia, and the ring wall manifested an apparent increase in signal intensity after enhancement. The patient was suspected of glioma at the local hospital and was transferred to our hospital. Twelve hours after hospitalization, the patient was suspected of developing cerebral palsy and thus underwent emergency surgery including lesion resection in the left basal ganglia, resection of the polus temporalis, and a decompressive craniotomy. Postoperative pathology confirmed brain abscess. The patient was eventually conscious, but left the right limb hemiplegia. Hence, when a patient develops the classical triad of fever, headache, and focal neurologic deficits, the possibility of brain abscess should be investigated. Early diagnosis and treatment are crucial to minimize various complications and the number of deaths.

Bacterial Infections of the Central Nervous System

Bacterial infections of the central nervous system (CNS) continue to be an important cause of morbidity and mortality in children. The spectrum of bacterial infection of CNS includes; focal or multifocal infections like brain abscesses or subdural empyema; or more generalized or diffuse infections like pyogenic meningitis or ventriculitis. Focal and generalized infections may co-exist in an individual patient. Prompt and adequate antibiotic therapy and occasionally neurosurgical interventions are the cornerstone of effective management. The recent emergence of several multidrug-resistant bacteria poses a threat to the effective management of bacterial CNS infections. Several adjunctive anti-inflammatory and neuroprotective therapies are being tried, however; none has made a remarkable impact on the outcome. Consequently, bacterial CNS infections in children still remain a challenge to manage. In this review, authors discuss the current updates on the diagnostic and therapeutic aspects of bacterial infections of the CNS in children (post-neonatal age group).

Spontaneous cerebral abscess due to Bacillus subtilis in an immunocompetent male patient: A case report and review of literature

BACKGROUND

Bacillus subtilis (B. subtilis) is considered a non-pathogenic microorganism of the genus Bacillus and a common laboratory contaminant. Only scarce reports of B. subtilis central nervous system infection have been reported, mainly in the form of pyogenic meningitis, usually in cases of direct inoculation by trauma or iatrogenically.

CASE SUMMARY

A 51-year-old man, with a free previous medical history, presented to the Emergency Department of our hospital complaining of recurrent episodes of left upper limb weakness, during the last month, which had been worsened the last 48 h. During his presentation in Emergency Department he experienced a generalized tonic-clonic grand mal seizure. Brain magnetic resonance imaging (MRI) scan with intravenous Gadolinium revealed a 3.3 cm × 2.7 cm lesion at the right parietal lobe surrounded by mild vasogenic edema, which included the posterior central gyrus. The core of the lesion showed relatively homogenous restricted diffusion. Post Gadolinium T1W1 image, revealed a ring-shaped enhancement. Due to the imaging findings, brain abscess was our primary consideration. Detailed examination for clinical signs of infectious foci revealed only poor oral hygiene with severe tooth decay and periodontal disease, but without detection of dental abscess. The patient underwent surgical treatment with right parietal craniotomy and total excision of the lesion. Pus and capsule tissue grew B. subtilis and according to antibiogram intravenous ceftriaxone 2 g bids was administered for 4 wk. The patient remained asymptomatic and follow-up MRI scan two months after operation showed complete removal of the abscess.

CONCLUSION

This case highlights the ultimate importance of appropriate oral hygiene and dental care to avoid potentially serious infectious complications and second, B. subtilis should not be considered merely as laboratory contaminant especially when cultivated by appropriate central nervous system specimen.

Management of brain abscesses: where are we now?

INTRODUCTION

Brain abscesses affect all age groups and are not peculiar to a particular country, race, or geographical location. It is a disease that, in the past, carried a high morbidity and mortality. With improvements in medical technology and expertise, outcomes have improved tremendously. The causative organisms vary vastly and have evolved with time. Treatment of brain abscesses is primarily with antimicrobial therapy but surgery plays a vital role in achieving better outcomes.

CONTENT

In this article, we review the literature to find out how the epidemiology of this disease has changed through the years and re-visit the basic pathological process of abscess evolution and highlight the new research in the biochemical pathways that initiate and regulate this process. We also highlight how magnetic resonance imaging and its various modalities have improved diagnostic accuracy. Finally, we discuss the pros and cons of traditional open surgery versus newer minimally invasive methods.

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

PURPOSE

To describe the presentation and management of bacterial brain abscess and subdural empyema in adults treated at two tertiary centers. In addition, to identify factors that may predict a poor clinical outcome.

METHODS

A retrospective analysis of data obtained from clinical records was performed, followed by multivariate regression analysis of patient and treatment-related factors.

RESULTS

113 patients were included with a median age of 53 years and a male preponderance. At presentation symptoms were variable, 28% had a focal neurological deficit, and 39% had a reduced Glasgow coma scale (GCS). Brain abscesses most frequently affected the frontal, temporal, and parietal lobes while 36% had a subdural empyema. An underlying cause was identified in 76%; a contiguous ear or sinus infection (43%), recent surgery or trauma (18%) and haematogenous spread (15%). A microbiological diagnosis was confirmed in 86%, with streptococci, staphylococci, and anaerobes most frequently isolated. Treatment involved complex, prolonged antibiotic therapy (> 6 weeks in 84%) combined with neurosurgical drainage (91%) and source control surgery (34%). Mortality was 5% with 31% suffering long-term disability and 64% achieving a good clinical outcome. A reduced GCS, focal neurological deficit, and seizures at presentation were independently associated with an unfavorable clinical outcome (death or disability).

CONCLUSIONS

Complex surgical and antimicrobial treatment achieves a good outcome in the majority of patients with bacterial brain abscess and subdural empyema. Factors present at diagnosis can help to predict those likely to suffer adverse outcomes. Research to determine optimal surgical and antibiotic management would be valuable.

Listeria monocytogenes Brain Abscess: Controversial Issues for the Treatment-Two Cases and Literature Review

Listeria monocytogenes (LM) is an opportunistic pathogen, and the most common central nervous system manifestation is meningitis while listerial brain abscesses are rare. We describe 2 cases of brain abscess due to LM and a literature review. Only 73 cases were reported in the literature from 1968 to 2017. The mean age was 51.9, and the mortality rate was 27.3%. In 19% of cases, no risk factors for neurolisteriosis were identified. Blood cultures were positive in 79.5% while CSF or brain abscess biopsy material was positive in 50.8%. In 40% was started a monotherapy regimen while in 60% a combination therapy without substantial differences in mortality. Fifty-two percent underwent neurosurgery while 45.3% has been treated only with medical therapy. The mortality rates were, respectively, 13% and 38.2%. Only 25% of patients who were treated for ≤6 weeks underwent neurosurgery, while 80% of those who were treated for ≥8 weeks were operated. The mortality rates were, respectively, 12.5% and 0%, suggesting that a combined approach of surgery and prolonged medical therapy would have an impact on mortality. We believe that it is essential to carry out this review as brain abscesses are rare, and there are no definitive indications on the optimal management, type, and duration of therapy.

Case of Rickettsia typhi-induced Brain Abscess Mimicking Brain Tumor

Murine typhus is one of the most prevalent rickettsial infections in the world, caused by the bacterial genus Rickettsia. Though the disease manifests a relatively benign clinical course with fever, rash, and headache being the 3 classic symptoms, neurological complications may arise in patients that could become permanent. In this case study, a patient with a brain abscess caused by R typhi infection is described. Based upon the recent reemergence of arthropod-borne disease, the findings in this case are significant; R typhi can cause a brain abscess that mimics a brain tumor, which delays the diagnosis and appropriate management of the disease. Murine typhus should always be considered when performing the differential diagnosis of brain abscesses in South Korea.

Epidemiology of central nervous system infectious diseases: a meta-analysis and systematic review with implications for neurosurgeons worldwide

OBJECTIVECentral nervous system (CNS) infections cause significant morbidity and mortality and often require neurosurgical intervention for proper diagnosis and treatment. However, neither the international burden of CNS infection, nor the current capacity of the neurosurgical workforce to treat these diseases is well characterized. The objective of this study was to elucidate the global incidence of surgically relevant CNS infection, highlighting geographic areas for targeted improvement in neurosurgical capacity.METHODSA systematic literature review and meta-analysis were performed to capture studies published between 1990 and 2016. PubMed, EMBASE, and Cochrane databases were searched using variations of terms relating to CNS infection and epidemiology (incidence, prevalence, burden, case fatality, etc.). To deliver a geographic breakdown of disease, results were pooled using the random-effects model and stratified by WHO region and national income status for the different CNS infection types.RESULTSThe search yielded 10,906 studies, 154 of which were used in the final qualitative analysis. A meta-analysis was performed to compute disease incidence by using data extracted from 71 of the 154 studies. The remaining 83 studies were excluded from the quantitative analysis because they did not report incidence. A total of 508,078 cases of CNS infections across all studies were included, with a total sample size of 130,681,681 individuals. Mean patient age was 35.8 years (range: newborn to 95 years), and the male/female ratio was 1:1.74. Among the 71 studies with incidence data, 39 were based in high-income countries, 25 in middle-income countries, and 7 in low-income countries. The pooled incidence of studied CNS infections was consistently highest in low-income countries, followed by middle- and then high-income countries. Regarding WHO regions, Africa had the highest pooled incidence of bacterial meningitis (65 cases/100,000 people), neurocysticercosis (650/100,000), and tuberculous spondylodiscitis (55/100,000), whereas Southeast Asia had the highest pooled incidence of intracranial abscess (49/100,000), and Europe had the highest pooled incidence of nontuberculous vertebral spondylodiscitis (5/100,000). Overall, few articles reported data on deaths associated with infection. The limited case fatality data revealed the highest case fatality for tuberculous meningitis/spondylodiscitis (21.1%) and the lowest for neurocysticercosis (5.5%). In all five disease categories, funnel plots assessing for publication bias were asymmetrical and suggested that the results may underestimate the incidence of disease.CONCLUSIONSThis systematic review and meta-analysis approximates the global incidence of neurosurgically relevant infectious diseases. These results underscore the disproportionate burden of CNS infections in the developing world, where there is a tremendous demand to provide training and resources for high-quality neurosurgical care.

Otogenic brain abscesses: A systematic review

Objective

Otogenic brain abscesses are one of the most significant life-threatening complications of otologic infections. Given their low prevalence, otogenic brain abscesses require a high index of suspicion for diagnosis. In this systematic review, we aim to provide an analysis of otogenic brain abscesses and describe common clinical signs and symptoms, bacteriology, location, treatment options, morbidity, and mortality.

Data Sources

PubMed, Cochrane CENTRAL database, Google Scholar, and Scopus.

Methods

A systematic review of literature was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses recommendations. Variables assessed included clinical signs and symptoms, bacteriology, location, treatment, morbidity, and mortality.

Results

Twenty-nine studies met inclusion and exclusion criteria, corresponding to a total of 1307 otogenic abscess cases for review. Fifty-five percent of abscesses were found in the temporal lobe and 28% in the cerebellum. Most patients (88.3%) had a history of suppurative chronic otitis media. The most common symptoms were headache, altered mental status, papilledema, and meningeal irritation. Fever, nausea, and vomiting affected about 40% of patients. The most commonly cultured bacterial species was Proteus mirabilis. In addition to antibiotics, most otogenic brain abscesses were treated by burr hole aspiration. Average mortality following advent of computed tomography was 8.11%.

Conclusion

Although rare, otogenic brain abscesses may occur as a complication of suppurative otitis media and require a high index of suspicion. Appropriate imaging studies and multidisciplinary expertise are crucial in the diagnosis and management.

Level of Evidence

4.