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

Imaging monitoring of Balamuthia granulomatous amoebic encephalitis

Balamuthia granulomatous amoebic encephalitis (GAE) is a rare and highly lethal infectious disease affecting the central nervous system, caused by the Balamuthia amoeba. This article reports the case of a child with normal immune function and no apparent epidemiological risk factors. In the initial stages, routine blood tests, cerebrospinal fluid cell tests, biochemical tests, and metagenomic next-generation sequencing (mNGS) were all normal. Surgical removal of the abscess and subsequent pathological diagnosis revealed a chronic granuloma. mNGS analysis of the brain abscess fluid identified Balamuthia mandrillaris (BM), leading to the diagnosis of Balamuthia GAE, after which antiparasitic treatment was initiated. This case underscores the importance of sustained imaging surveillance in suspected cases of Balamuthia GAE.

Influence of laboratory and radiographic parameters on the clinical presentation and outcome of surgically treated patients with primary brain abscesses

BACKGROUND

Brain abscesses can lead to severe clinical outcomes, including death. Most studies on brain abscesses focus either on patient cohorts including postsurgical/posttraumatic abscesses. This study aimed to assess the clinical presentation and postoperative outcomes in a homogeneous group of patients with primary, pyogenic brain abscesses who underwent surgical treatment.

METHODS

We retrospectively analyzed consecutive patients with pyogenic brain abscesses treated surgically at our center from 2008 to 2023. The primary endpoint was a modified Rankin Scale (mRS) score of ≥ 3 at discharge. Secondary endpoint was preoperative clinical status (mRS ≥ 3). We statistically correlated clinical, radiographic, and microbiological parameters with these endpoints.

RESULTS

A total of 60 patients (36.7% female) with a mean age of 48.5 ± 20.8 years were included in this study. Six patients (10.0%) had an unfavorable postoperative outcome, including two deaths (3.3%). Significant risk factors for poor outcomes included preoperative disturbance of consciousness (DOC) (p = 0.012) and elevated preoperative C-reactive protein (CRP) levels (p = 0.002). Larger abscess volume (37.4 mL vs. 16.1 mL, p = 0.065) and shorter mean distance to the ventricles (3 mm vs. 11.42 mm, p = 0.086) trended toward significance. The length of intensive care unit (ICU) stay was significantly longer for patients with unfavorable outcomes (p = 0.001). Upon admission, eighteen patients (30.0%) had an mRS score of ≥ 3. Elevated leukocyte count was identified as a significant risk factor for poor preoperative status (p = 0.007). Median clinical performance, measured by mRS, improved throughout the treatment course and during follow-up from 2 to 0.

CONCLUSIONS

Preoperative DOC and elevated CRP levels were identified as predictors of unfavorable outcomes. Elevated leukocyte count was a predictor for poor preoperative status.

Vancomycin versus linezolid for treatment of staphylococcal-associated central nervous system infections

BACKGROUND

Linezolid and vancomycin are both recommended for the treatment of staphylococcal-associated central nervous system (CNS) infections. However, to date, no data are available comparing the outcomes of patients treated with vancomycin or linezolid for these infections. The aim of this study was to compare the incidence of treatment failure and adverse events (AEs) associated with vancomycin and linezolid in staphylococcal-associated CNS infections.

METHODS

This retrospective monocentric observational study was conducted between 01/01/2015 and 31/12/2023. All patients with a confirmed staphylococcal associated CNS infection and treated with vancomycin or linezolid were included. Failure of antimicrobial treatment was the primary outcome of interest, defined by a composite criteria: persistence of infection (i.e. positive culture after > 72 h of antimicrobial treatment active on the isolated bacteria), relapse of infection (i.e. new infection with the same bacteria involved in the initial episode) or infection related death. Second outcome of interest was AE incidence related to linezolid or vancomycin. Outcomes were analysed using survival analysis techniques and propensity score.

RESULTS

Ninety one patients were included: 51 in vancomycin group and 40 in linezolid group. Infections were mainly meningitis (n = 71; 78%). Median duration of linezolid or vancomycin treatment was 7 days (IQR 4; 13). Treatment failure occurred in 18.6% (n = 17) of patients (infection persisted in 9.8% of patients (n = 9), infection relapsed in 6.6% (n = 6) and infection caused a fatal outcome in 4.4% (n = 4). In the Cox proportional hazards regression model, vancomycin was not associated with treatment failure (aHR 2.90; 95% CI [0.93-9.30]; p = 0.066). Using propensity score, vancomycin was associated with treatment failure (HR 3.28; 95% CI [1.02-10.54]; p = 0.045). Treatment with vancomycin was also associated with AE (HR 8.42; CI 95% [2.44;29.10]; p = 0.019).

CONCLUSION

Patients treated with vancomycin for staphylococcal-associated CNS infections seems to have a higher risk of treatment failure and AE compared to those treated with linezolid. However, given the low statistical power and the observational nature of this study, further research is needed to confirm these findings.

Diagnostic utility of next-generation sequencing in neurological infections: Two cases in point

We report the successful management of two cases of brain abscess and subdural empyema caused by Fusobacterium nucleatum and Streptococcus intermedius diagnosed using 16S ribosomal RNA (rRNA) sequencing where microbiological culture showed no growth. This report elucidates the utility of next-generation sequencing (NGS) in determining the microbial etiology and guiding appropriate antimicrobial treatment in life-threatening neurological infections.

Clinicodemographic and Radiological Features of Infective Ring-Enhancing Brain Lesions: A 4-Year Retrospective Study at a Tertiary Referral Center

Background

The diagnostic evaluation of ring-enhancing brain lesions (REBLs) is challenging, especially in immunocompromised patients. We conducted a retrospective study to describe the clinicodemographic and radiological features among patients presenting with REBLs to a tertiary referral center.

Methods

Radiological reports of all patients who underwent brain computed tomography or magnetic resonance (MR) imaging between 1 November 2013 and 31 October 2017 were filtered for terms indicative of REBLs. Infectious diseases physicians reviewed the medical records to confirm the diagnosis.

Results

Over the 4-year study period, there were 42 patients with infective REBLs and 249 with neoplastic REBLs. Pyogenic brain abscesses (PBAs) (20 of 42 [47.6%]) were the most common cause of infective REBLs, followed by tuberculous brain abscesses (TBAs) (9 of 42 [21.4%]) and Nocardia brain abscesses (NBAs) (6 of 42 [14.3%]). The patients were predominantly male, with a mean age of 55.2 years. Fewer than half were febrile at presentation. Cerebrospinal fluid investigations established the microbiological diagnosis in fewer than half of those who underwent lumbar puncture or extraventricular drain insertion. Conversely, brain biopsy yielded the microbiological diagnosis in almost all patients (16 of 17) who underwent the operation. Median white blood cell counts and C-reactive protein were higher in those with PBAs or NBAs than in those with TBAs. All with PBAs and NBAs who underwent MR imaging had diffusion-weighted imaging-hyperintense lesions, compared with only about half of those with TBAs.

Conclusions

Our study has revealed important distinguishing features between infective REBLs and neoplastic REBLs and between PBAs, TBAs, and NBAs.

Clinical outcomes of neuroendoscopic resection of brain abscess guided by electromagnetic navigation among patients presenting at Jieyang People's Hospital in China

Background

The treatment of brain abscesses presents certain difficulties. How to enhance the surgical effect and the positive rate of bacterial culture has always been our objective.

Aim

This study explored the surgical outcome of neuroendoscopic resection of brain abscess under the guidance of electromagnetic navigation and how to increase the positive rate of bacterial culture.

Methods

From June 2018 to December 2023, a total of 5 cases of neuroendoscopic resection of brain abscess under the guidance of electromagnetic navigation were conducted in our hospital. After admission, enhanced head MR layer scans were carried out. The imaging data were imported into the neuronavigation system. After successful registration, the abscess wall was cauterized with bipolar under the guidance of electromagnetic navigation, and the abscess wall was taken for bacterial culture and drug sensitivity test. We calculated the positive rate of bacterial culture, that is, the positive rate of bacterial culture is the number of positive cases of bacterial culture divided by the total number of cases sent for culture. After the operation, sensitive antibiotics were intravenously administered according to the bacterial culture and drug sensitivity test.

Results

The headache symptoms of the 5 patients were significantly alleviated, and there was no residual limb dysfunction. Reexamination of the head MR indicated that the abscess was significantly reduced. Five cases were all subjected to bacterial culture, among which bacteria were cultured in three cases, and the positive rate of bacterial culture was 60 %. The abscess clearance rate after the operation was all greater than 80 %.

Conclusion

Neuroendoscopic resection of brain abscess under the guidance of electromagnetic navigation has a favorable effect.This surgical method increases the positive rate of bacterial culture and holds significant reference significance for the subsequent intravenous administration of antibacterial drugs.

Actinomyces israelii Brain Abscess With Advanced HIV Disease

We present the first reported case of a pediatric central nervous system (CNS) abscess caused by Actinomyces israelii in the context of advanced HIV disease. A three-year-old girl from São Tomé and Príncipe presented with progressive neurological deficits, including gait instability and language delay. Brain MRI revealed a right temporal lobulated lesion with surrounding edema and mass effect. Chronic superior sagittal sinus thrombosis and hydrocephalus were also identified. Neurosurgical intervention included ventriculocisternostomy and microsurgical resection of the lesion, which revealed a multiloculated abscess. Histology confirmed granuloma formation, and polymerase chain reaction (PCR) identified A. israelii. HIV serology was positive, with a CD4 count of 664 cells/μL and a viral load of 1,340,000 copies/mL. The patient received a year-long antibiotic regimen, starting with intravenous penicillin G followed by oral amoxicillin, and antiretroviral therapy was initiated. She showed marked improvement in neurological function and no signs of relapse after one year. This case underscores the importance of considering A. israelii in the differential diagnosis of CNS lesions in immunocompromised pediatric patients. It also highlights the critical role of neurosurgery, molecular diagnostics, and multidisciplinary management in ensuring favorable outcomes.

Canadian Association of Radiologists Central Nervous System Diagnostic Imaging Referral Guideline

The Canadian Association of Radiologists (CAR) Central Nervous System Expert Panel is made up of physicians from the disciplines of radiology, emergency medicine, neurosurgery, and neurology, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 24 clinical/diagnostic scenarios, a rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 55 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 51 recommendation statements across the 24 scenarios. This guideline presents the methods of development and the referral recommendations for congenital disorders of the brain, cerebrovascular disease, multiple sclerosis and demyelinating disease, headache, concussion, pituitary and juxtasellar lesions, cranial neuropathy, brain stem symptoms, altered intracranial pressure (hypertension, hypotension, hydrocephalus suspected shunt malfunction, normal pressure hydrocephalus), vestibular and cochlear symptoms (hearing loss, vertigo), mental status change (acute, dementia/memory loss), visual loss, epilepsy and seizure, CNS infection, intracranial space-occupying lesions, suspected cerebral venous sinus thrombosis, vasculitis, movement disorders/Parkinsonism, metabolic and toxic encephalopathies, and aneurysm screening.

TWENTY-THREE PEDIATRIC CASES OF CITROBACTER KOSERI MENINGITIS IN THE LAST 20 YEARS: STILL A DRAMATIC PROGNOSIS

Among 7578 cases of pediatric bacterial meningitis recorded in France (2001-2021), including 1313 neonatal cases, 23/7578 (0.3%) and 18/1313 (1.4%) were due to Citrobacter koseri. Median age was 11 days. About 63.6% of patients were hospitalized in intensive care unit. Cerebral abscesses were observed in 77.8% and the mortality rate was 22.7%.

Listeria monocytogenes and Staphylococcus aureus coinfection in a patient with multiple myeloma: Case report

Introduction

Listeria monocytogenes is a formidable pathogen that poses a significant threat to immunocompromised and might cause rare atypical forms of the disease especially complicated with Staphylococcus aureus coinfection.

Case

We present a case of a patient with L. monocytogenes meningoencephalitis, endocarditis, sepsis, and S. aureus osteomyelitis, highlighting the complexities of managing disseminated polymicrobial infection. A 64-year-old female with multiple myeloma treated with chemotherapy presented with fever, altered mental status, nausea, and diarrhea to the emergency department. During the physical examination, the patient was feverish, had a hemorrhagic rash and an abscess on the right thumb. Neurologically - nuchal rigidity was seen and the finger-nose test was abnormal. Blood tests and cerebrospinal fluid analysis were consistent with bacterial meningitis. The roentgenogram revealed osteomyelitis involving the right thumb. Later L. monocytogenes was identified in blood and cerebrospinal fluid cultures. The abscess was drained, and pus culture identified S. aureus. Echocardiography revealed vegetation on the aortic valve. The patient was initially treated with ceftriaxone, ampicillin, gentamicin, with clindamycin and ciprofloxacin for osteomyelitis and later with ampicillin/sulbactam and ciprofloxacin to cover both pathogens and pathologies. Due to an allergic reaction to ampicillin, treatment was changed to vancomycin. After 4 weeks of antibiotic therapy patient fully recovered and continued chemotherapy for multiple myeloma.

Conclusion

In conclusion, this case emphasizes the intersection of hematological malignancy, chemotherapy-related immunosuppression, and subsequent severe disseminated bacterial infections and coinfections. Prompt diagnosis and adequate treatment of the disease and its complications is key to the successful recovery.

Therapeutic Drug Monitoring-Guided Linezolid Therapy for the Treatment of Multiple Staphylococcal Brain Abscesses in a 3-Month-Old Infant

Brain abscesses are invasive infections of the central nervous system with a high level of treatment complexity especially in pediatric patients. Here, we describe a 3-month-old infant with multiple brain abscesses caused by methicillin-susceptible Staphylococcus aureus (MSSA). The patient was initially treated with empirical antibiotics (ceftriaxone, metronidazole, vancomycin). Upon MSSA identification, therapy was optimized by switching vancomycin to linezolid to improve tissue penetration. Therapeutic drug monitoring (TDM) was performed to check linezolid levels in the plasma and pus of the abscess, confirming drug penetration into brain tissue. A two-stage surgical drainage approach, consisting of repeated pus aspiration through an intracystic catheter, was then performed to achieve a significant reduction in abscess size. After nine weeks of antibiotic therapy, the patient was discharged in good clinical condition. This case highlights the role of linezolid for the treatment of complicated CNS infections and the importance of a multidisciplinary approach, combining TDM-based antibiotic therapy with timely and eventually repeated surgery, in order to effectively treat brain abscesses.

Managing Intracranial Pressure Crisis

PURPOSE OF REVIEW

The objective of this review is to provide a comprehensive management protocol for the treatment of intracranial pressure (ICP) crises based on the latest evidence.

RECENT FINDINGS

The review discusses updated information on various aspects of critical care management in patients experiencing ICP crises, including mechanical ventilation, fluid therapy, hemoglobin targets, and hypertonic saline infusion, the advantages of ICP monitoring, the critical ICP threshold, and bedside neuromonitoring. All aspects of critical care treatment, including hemodynamic and respiratory support and adjustment of ICP reduction therapy, may impact patient outcomes. ICP monitoring allows ICP values, trends, waveforms, and CPP calculation, which are helpful to guide patient care. Advanced neuromonitoring devices are available at the bedside to diagnose impaired intracranial compliance and intracranial hypertension, assess brain function, and optimize cerebral perfusion. Future research should focus on developing appropriate intervention protocols for both invasive and noninvasive neuromonitoring in managing ICP crisis patients.

Brain abscess following solid organ transplantation: A 21-year retrospective study

BACKGROUND

Development of brain abscess following solid organ transplantation is associated with significant morbidity and mortality. We undertook a descriptive study to evaluate the etiology, clinical manifestations, diagnosis, management, and outcomes of brain abscess in solid organ transplant (SOT) recipients at three major transplant centers in the United States.

METHODS

This is a retrospective study of adults with brain abscess following SOT between January 2000 and June 2021 at Mayo Clinic sites in Arizona, Minnesota, and Florida.

RESULTS

A total of 39 patients were diagnosed with a brain abscess following SOT. The most common pathogens were Nocardia sp. (24 cases, 61.5% [Nocardia farcinica, 37.5%]), followed by fungi (12 cases, 30.7% [Aspergillus sp., 83.3%]). The majority were kidney transplant recipients (59%). Median time to brain abscess diagnosis was 1.3 years (range, 29 days-12 years) after SOT; 10 of 12 patients (83%) with fungal brain abscess were diagnosed within 1 year after SOT. Twelve patients underwent brain biopsy for diagnosis (25% Nocardia vs. 50% fungal), eight (20.5%) underwent surgical resection of the abscess, and 31 (79.5%) received antimicrobial therapy alone. Median time to brain abscess resolution was 166 days for Nocardia and 356 days for fungal pathogens. Eleven of 39 patients (28.2%) died as a result of their brain abscess, including four of 24 patients (16%) with Nocardia and six of 10 patients (60%) with Aspergillus brain abscess. All-cause mortality was 43.6%.

CONCLUSION

Brain abscess remains an uncommon infectious complication following SOT. Nocardia and fungi accounted for 92% of pathogens in our cohort. Fungal brain abscess portends a poor prognosis.

Altered Mental Status in Cancer

Patients with cancer experience high rates of alterations in mental status. The mechanisms for altered mental status (AMS) in this population are manifold. The cancer itself may cause AMS through direct invasion of the central nervous system or as metastatic leptomeningeal spread. However, cancer patients are also vulnerable to tumor-associated complications such as seizures, cerebral edema, strokes, or cancer treatment-related complications such as infections, direct neural injury from radiation or chemotherapy, edema, or dysregulated autoimmune response from immunotherapies. Both during treatment and as sequelae, patients may suffer neurocognitive complications from chemotherapy and radiation, medications or opportunistic infections, as well as toxic-metabolic, nutritional, and endocrine complications. In this review, we describe a clinical approach to the cancer patient presenting with AMS and discuss the differential drivers of AMS in this patient population. While common etiologies of AMS in noncancer patients (toxic-metabolic or infectious encephalopathy, delirium) are also applicable to cancer patients, we additionally provide a cancer-specific differential diagnosis that warrants special consideration in the cancer patient with AMS.

Extended sequential intravenous and oral antimicrobial therapy improves cure rate in postoperative intracranial neurosurgical infections: a Spanish multicenter retrospective study

BACKGROUND

Postoperative intracranial neurosurgical infections (PINI) complicate < 5% neurosurgeries. Scarce attention was dedicated to the extension and characteristics of its antimicrobial management considering their high morbidity, not negligible mortality, delayed hospital stay and increased healthcare costs.

METHODS

We analyzed retrospectively (2014-2023) 162 PINI from eight Spanish third-level academic hospitals.

RESULTS

Elective clean craniotomies after tumor or vascular causes were the leading procedures. Epidural abscess (24.7%), scalp infections (19.8%), postsurgical meningitis (16.7%) and cranioplasty infections (16.7%) were the most frequent PINI. Gram negative bacteria (38.6%) and Staphylococcus spp (28.6%) were the predominant isolates. Overall 85.2% patients underwent pus drainage, mostly by craniotomy (40.3%). Interestingly 34% were already receiving antibiotics for extracranial infections before developing PINI while 16.8% did not receive pre-operative antibiotic prophylaxis. In total 77.2% patients started a combined intravenous (IV) antimicrobial therapy, of which 85.2% switched after 5 days to a second-line IV antibiotic regimen, in 41.3% cases combined, after pus culture results, for a median of 21 days. Overall 61.1% patients continued on oral antimicrobials after hospital discharge, 30.3% as a combined regimen, for a median of 42 days. Complete cure was obtained in 81.5% cases, while 11.1% relapsed, 7.4% failed to cure and 6.8% died after PINI complications. In the multivariate analysis oral antimicrobial therapy after hospital discharge (p = 0.001) was significantly associated with PINI cure with no effect on survival.

CONCLUSIONS

We conclude that an extended 6 weeks sequential IV and oral antimicrobial therapy in addition to neurosurgical correction increases PINI cure rate with no effect on survival.

CLINICAL TRIAL NUMBER

Not applicable.

Infectious brain abscesses and granulomas: analysis of 110 episodes in adults

BACKGROUND

Infectious brain abscesses and granulomas, characterized by localized collections of pus or inflammatory tissue within the brain parenchyma, pose significant clinical challenges due to their potentially life-threatening nature and complex management requirements.

METHODS

This cross-sectional study investigated patients diagnosed with infectious brain abscesses and granulomas from March 1, 2012, to October 22, 2021, in Mashhad, Iran. Data were collected from adult patients admitted to the two primary referral centers for community-acquired neuroinfections and neuroinflammations. Demographic information, clinical features, laboratory and neuroimaging characteristics, and clinical outcomes were analyzed.

RESULTS

A total of 110 episodes were identified in 106 patients, with a median age of 45 years (IQR 30-56.3) and 62.7% male. Predisposing conditions included immunocompromised states (27.5%), preceding otitis/mastoiditis (16.2%), sinusitis (13.3%), and pulmonary infections (17.2%). The most common clinical manifestations were headache (57.3%), fever (49.1%), altered consciousness (44.4%), and seizures (31.8%). Neuroimaging revealed that brain lesions were solitary in 51% and multiple in 48% of episodes. Surgical intervention was performed in 46.4% of cases. The in-hospital mortality rate was 24.5%, with significant associations found between mortality and factors such as age, altered consciousness, multiple brain lesions, and cerebellum and brainstem involvement. The median length of hospital stay was 28 days (IQR 16-46.5).

CONCLUSION

Our study underscores challenges in diagnosing and treating brain abscesses and granulomas, with high mortality rates (24.5%) despite advanced techniques. Age, altered consciousness, and lesion characteristics predict death. Addressing changing microbial patterns and improving diagnostics are vital for better outcomes, especially in low- and middle-income countries.

Intraventricular antibiotics for severe central nervous system infections: a case series

Severe central nervous system infections (CNSI), including community-acquired CNSI (CA-CNSI) and healthcare-associated ventriculitis and meningitis (HAVM), present high morbidity and mortality. Intraventricular antibiotic treatment (IVT) is advisable for these infections, though evidence is limited. We retrospectively analyzed data on 27 patients who received IVT for severe CA-CNSI and HAVM over 10 years, assessing clinical and paraclinical features, such as baseline severity and functional outcome, antibiotics, microbiological and laboratory data. Comparisons were made between patients affected by CNSI and HAVM and those with favorable and unfavorable outcomes, based on the modified Rankin scale. Gram-positive organisms dominated in CA-CNSI (64%), while gram-negative organisms were more frequent in HAVM (64%). Patients received a median of 30 days of intravenous antibiotics and 11 days of IVT, with no significant difference between CA-CNSI and HAVM. IVT-associated toxicity was rare. Patients with favorable outcomes (64%) had higher initial cerebrospinal fluid- white blood cell count (CSF-WBC), that decreased more rapidly than in patients with unfavorable outcomes. CSF-WBC dynamics did not differ between CA-CNSI and HAVM patients. Rapid decline in CSF-WBC after initiation of IVT was associated with favorable outcome. Despite severe neurological impairment at admission, most survivors achieved favorable long-term outcomes.

Brain Abscess Causes Brain Damage With Long-Lasting Focal Cerebral Hypoactivity that Correlates With Abscess Size: A Cross-Sectional 18F-Fluoro-Deoxyglucose Positron Emission Tomography Study

BACKGROUND AND OBJECTIVES

Bacterial brain abscesses may have long-term clinical consequences, eg, mental fatigue or epilepsy, but long-term structural consequences to the brain remain underexplored. We asked if brain abscesses damage brain activity long term, if the extent of such damage depends on the size of the abscess, and if the abscess capsule, which is often left in place during neurosurgery, remains a site of inflammation, which could explain long-lasting symptoms in patients with brain abscess.

METHODS

2-[18F]-fluoro-2-deoxy-D-glucose positron emission tomography/computed tomography (FDG-PET/CT), electroencephalography, and MRI were performed 2 days to 9 years after neurosurgery for bacterial brain abscess.

RESULTS

FDG-PET/CT revealed hypometabolism in the neocortex or cerebellum overlying the previous bacterial abscess in 38 of 40 patients. The larger the abscess, the greater was the extent of the subsequent hypometabolism (r = 0.63; p = 3 × 10-5). In 9 patients, the extent of subsequent hypometabolism seemed to coincide with the extent of peri-abscess edema in the acute phase. Follow-up MRI after ≥1 year in 9 patients showed focal tissue loss and gliosis. In 13 patients with abnormal electroencephalography recordings, abnormalities extended beyond the cerebral lobe affected by the abscess, indicating damage to wider brain networks. The abscess capsule had an FDG signal indicating inflammation only during the first week after neurosurgical pus drainage.

CONCLUSION

The bigger a brain abscess is allowed to grow, the more extensive is the long-term focal reduction in brain activity. This finding emphasizes the need for rapid neurosurgical intervention. The abscess capsule does not display long-lasting inflammation and probably does not explain long-term symptoms after brain abscess.

Augmented pathogen detection in brain abscess using metagenomic next-generation sequencing: a retrospective cohort study

Brain abscess is a severe infection characterized by the accumulation of pus within the brain parenchyma. Accurate identification of the causative pathogens is crucial for effective treatment and improved patient outcomes. This 10-year retrospective, single-center study aimed to compare the detection performance of conventional culture methods and metagenomic next-generation sequencing (mNGS) in brain abscess. We reviewed 612 patients diagnosed with brain abscess and identified 174 cases with confirmed etiology. The median age was 52 years, with 69.5% males. Culture tests predominately identified gram-positive bacteria, particularly Streptococcus spp. Gram-negative bacteria, including Klebsiella spp., were also detected. However, mNGS revealed a more diverse pathogen spectrum, focusing on anaerobes (e.g., Fusobacterium spp., Parvimonas spp., Porphyromonas spp., Prevotella spp., and Tannerella spp.). mNGS exhibited significantly higher overall pathogen-positive rates in pus samples (85.0% vs 50.0%, P = 0.0181) and CSF samples (84.2% vs 7.9%, P < 0.0001) compared to culture. Furthermore, the detection rates for anaerobes displayed a notable disparity, with mNGS yielding significantly higher positive detections in both pus samples (50.0% vs 10%, P = 0.0058) and CSF samples (18.4% vs 0%, P = 0.0115) when compared to culture methods. The assistance of mNGS in pathogen detection, particularly anaerobes in brain abscess, was evident in our findings. mNGS demonstrated the ability to identify rare and fastidious pathogens, even in culture-negative cases. These results emphasize the clinical value of mNGS as a supplement for brain abscess, enabling more comprehensive and accurate pathogen identification.IMPORTANCEThe accurate identification of pathogens causing brain abscess is crucial for effective treatment and improved patient outcomes. In this 10-year retrospective study, the detection performance of conventional culture methods and metagenomic next-generation sequencing (mNGS) was compared. The study analyzed 612 patients with brain abscess and confirmed etiology in 174 cases. The results showed that culture tests predominantly identified gram-positive bacteria, while mNGS unveiled a broader diverse pathogen spectrum, particularly anaerobes. The mNGS method exhibited significantly higher overall rates of pathogen positivity both in pus and cerebrospinal fluid (CSF) samples, surpassing the culture methods. Notably, mNGS detected a significantly higher number of anaerobes in both pus and CSF samples compared to culture methods. These findings underscore the clinical value of mNGS as a supplement for brain abscess diagnosis, enabling more comprehensive and accurate pathogen identification, particularly for rare and fastidious pathogens that evade detection by conventional culture methods.

Brain abscesses: the first report of disseminated Nocardia beijingensis infection in an immunocompetent individual in China

Nocardia is widely distributed in the natural environment and typically cause opportunistic infections. However, it is important to note that the pathogenicity of different Nocardia species may vary significantly. Here we reported the first case of brain abscess caused by Nocardia beijingensis (N. beijingensis) infection in China. A 70-year-old male immunocompetent individual came to our hospital for treatment due to headache. After examination, it was found that he had a brain abscess caused by N. beijingensis. By utilizing a combination of surgical intervention and antibiotic therapy, the patient ultimately achieved full recovery. In addition, we isolated this strain and displayed its ultrastructure through scanning electron microscopy. The phylogenetic tree was analyzed by 16 S rRNA sequence. A literature review of N. beijingensis infections in all immunocompetent and immunocompromised patients was presented. It highlighted that abscess formation appears to be a common manifestation of N. beijingensis infection, and N. beijingensis has become an emerging pathogen in immunocompetent individuals.

Geriatric nutritional risk index has a prognostic value for recovery outcomes in elderly patients with brain abscess

Background

The Geriatric Nutritional Risk Index (GNRI) is a straightforward and objective tool for nutritional screening in older patients and has been demonstrated to possess prognostic predictive value in several diseases. Nonetheless, there is a lack of research on the nutritional risk associated with brain abscess in the older. This study aimed to evaluate the prevalence of nutritional risk among these patients by GNRI and to investigate its potential prognostic value for clinical outcomes.

Materials and methods

From August 2019 to April 2023, 100 older patients diagnosed with brain abscess were enrolled in this single-center prospective cohort study, which evaluated the prognostic value of the Geriatric Nutritional Risk Index (GNRI) in elderly brain abscess patients. Data collected included demographic, and clinical characteristics at admission and calculated the GNRI, and the Glasgow Outcome Scale (GOS) score 6 months post-discharge. A GOS score of 5 was considered indicative of a good recovery, whereas scores ranging from 1 to 4 were classified as poor recovery.

Results

The results revealed that 48% of older brain abscess patients were at risk of malnutrition according to the GNRI. These patients had significantly higher post-admission C-reactive protein (CRP) levels (p = 0.017), more comorbidities (p < 0.001), and higher age-adjusted Charlson Comorbidity Index (aCCI) scores (p < 0.001) compared to those without nutritional risk. Spearman correlation analysis showed that GNRI scores were negatively correlated with CRP levels, comorbidities, and aCCI scores, and positively correlated with Glasgow Outcome Scale (GOS) scores (Spearman's ρ = 0.624, p < 0.001). Multivariate logistic regression revealed that lower GNRI values were linked to reduced GOS levels (OR = 0.826, 95% CI: 0.775-0.880). ROC analysis determined a GNRI threshold of 97.50 for predicting poor recovery, with 90.57% sensitivity and 87.23% specificity.

Conclusion

The older brain abscess patients exhibited a high malnutrition risk. GNRI showed an important predictive value for recovery in older patients, which could be helpful in clinical intervention and rehabilitation.

Comparison of surgical outcomes between primary and secondary brain abscess

Brain abscess (BA) constitutes 1-8% of intra-cerebral tumors, and thus the present study aimed to compare the surgical outcomes of patients with primary and secondary BA. The present retrospective study examined 32 of cases BA who underwent surgery in a local institution between February, 2013 and December, 2023. All patients received intravenous antibiotic therapy according to the antibiogram for antimicrobial susceptibility. In total, 32 patients were separated into two groups as follows: Group A (16 patients, 50%) with primary abscess and group B (16 patients, 50%) with secondary abscess. Of the 32 patients included in the study, 23 (71.8%) were males, and the median age was 55.3 years. On the whole, the present study demonstrates that a multidisciplinary approach involving a combination of often multiple surgical procedures and prolonged antibiotic medication may improve the functional outcome if the underlying pathology allows for a functional outcome.

Surgical Management of Tuberculosis-related Cerebral Disorders: A Retrospective Single-center Study

BACKGROUND

Tuberculosis (TB) remains a significant global health concern, with extrapulmonary manifestations, including central nervous system involvement, posing substantial morbidity and mortality. While medical treatment with anti-TB drugs is the mainstay of therapy, certain TB-related cerebral complications, such as hydrocephalus, abscesses, and large symptomatic tuberculomas, may require surgical intervention. This study aimed to evaluate the outcomes of surgical management in patients with TB-related cerebral disorders.

METHODS

A retrospective analysis was conducted on 24 patients who underwent surgical intervention for TB-related cerebral disorders, including tuberculomas, hydrocephalus, and abscesses, at a tertiary care center between 2005 and December 2020. Demographic data, clinical presentations, radiological findings, surgical techniques, and treatment outcomes were analyzed.

RESULTS

The study cohort had a mean age of 35.8 ± 13.6 years, and the majority (62.5%) were male. Underlying immunodeficiency, primarily HIV infection, was present in 75% of the patients. The most common presenting symptoms were headache (83.3%), focal neurological deficits (75%), and altered mental status (54.2%). Radiological findings revealed 13 (54.2%) tuberculomas, 8 (33.3%) instances of hydrocephalus, and 3 (12.5%) abscesses. VP shunt inserted in 8 (33.3%) cases. Microscopic craniotomy performed in 7 (29.16%) cases. Aspiration through burr hole was done in 3 (12.5%) cases and stereotactic biopsy was performed in 6 (25%) cases. After 12 months of follow-up, favorable outcome achieved in 18 cases (75%) and the mortality occurred in 2 patients (8.3%). Surgical interventions included lesion resection (n = 10), stereotactic biopsy (n = 7), and ventriculoperitoneal (VP) shunt placement (n = 7). At 12-month follow-up, 18 (75%) patients had a favorable outcome, defined as clinical improvement or stabilization. Unfavorable outcomes were observed in 6 (25%) patients, including 2 deaths.

CONCLUSION

Surgical management, in conjunction with appropriate anti-TB medical therapy, may be a valuable component of the comprehensive treatment approach for select patients with TB-related cerebral disorders. The favorable outcome rate observed in this study suggests that timely and tailored surgical intervention can contribute to improved patient outcomes. However, larger, prospective, multicenter studies are needed to further elucidate the role and long-term efficacy of surgical management in this patient population.

Update and approach to patients with brain abscess

PURPOSE OF REVIEW

The epidemiology of brain abscess has changed in recent decades. Moreover, acute and long-term management remains challenging with high risks of mortality and neurological sequelae. This review describes recent advances in epidemiology, diagnosis, and treatment of brain abscess.

RECENT FINDINGS

The incidence of brain abscess is increasing, especially among elderly individuals. Important predisposing conditions include dental and ear-nose-throat infections, immuno-compromise, and previous neurosurgery. Molecular-based diagnostics have improved our understanding of the involved microorganisms and oral cavity bacteria including anaerobes are the predominant pathogens. The diagnosis relies upon a combination of magnetic resonance imaging, neurosurgical aspiration or excision, and careful microbiological examinations. Local source control by aspiration or excision of brain abscess combined with long-term antimicrobials are cornerstones of treatment. Long-term management remains important and should address neurological deficits including epilepsy, timely diagnosis and management of comorbidities, and potential affective disorders.

SUMMARY

A multidisciplinary approach to acute and long-term management of brain abscess remains crucial and source control of brain abscess by neurosurgery should be pursued whenever possible. Numerous aspects regarding diagnosis and treatment need clarification. Nonetheless, our understanding of this complicated infection is rapidly evolving.

Cerebral Infectious Opportunistic Lesions in a Patient with Acute Myeloid Leukaemia: The Challenge of Diagnosis and Clinical Management

Central nervous system (CNS) lesions, especially invasive fungal diseases (IFDs), in immunocompromised patients pose a great challenge in diagnosis and treatment. We report the case of a 48-year-old man with acute myeloid leukaemia and probable pulmonary aspergillosis, who developed hyposthenia of the left upper limb, after achieving leukaemia remission and while on voriconazole. Magnetic resonance imaging (MRI) showed oedematous CNS lesions with a haemorrhagic component in the right hemisphere with lepto-meningitis. After 2 weeks of antibiotics and amphotericin-B, brain biopsy revealed chronic inflammation with abscess and necrosis, while cultures were negative. Clinical recovery was attained, he was discharged on isavuconazole and allogeneic transplant was postponed, introducing azacitidine as a maintenance therapy. After initial improvement, MRI worsened; brain biopsy was repeated, showing similar histology; and 16S metagenomics sequencing analysis was positive (Veilonella, Pseudomonas). Despite 1 month of meropenem, MRI did not improve. The computer tomography and PET scan excluded extra-cranial infectious-inflammatory sites, and auto-immune genesis (sarcoidosis, histiocytosis, CNS vasculitis) was deemed unlikely due to the histological findings and unilateral lesions. We hypothesised possible IFD with peri-lesion inflammation and methyl-prednisolone was successfully introduced. Steroid tapering is ongoing and isavuconazole discontinuation is planned with close follow-up. In conclusion, the management of CNS complications in immunocompromised patients needs an interdisciplinary approach.

Antibiotic treatment of neuro-meningeal infections

In France, conjugated pneumococcal vaccination has considerably modified the profile of pneumococcal meningitis by eliminating the most virulent strains resistant to beta-lactams. Over recent years, the nationwide pediatric meningitis network of the Pediatric Infectious Disease Group (GPIP) and the National Reference Centre of Pneumococci have not recorded any cases of meningitis due to pneumococcus resistant to third-generation cephalosporins (C3G), even though in 2021, strains with a less favorable profile appeared to emerge. These recent data justify renewal of the 2016 recommendations and limitation of vancomycin to the secondary phase of treatment of pneumococcal meningitis when the MIC of the isolated strain against injectable C3Gs is >0.5 mg/L. The only major change proposed by the GPIP in this 2023 update of its recommendations is discontinuation of the recommendation of a combination of ciprofloxacin and cefotaxime in Escherichia coli meningitis in newborns and young infants. The nationwide observatory of meningitis in children is a valuable tool because of its completeness and its continuity over the past 15 years. The maintenance of epidemiological surveillance will allow us to adapt new therapeutic regimens to the evolution of pneumococcal susceptibility profiles and to future serotype-specific changes. Community-acquired cerebral abscesses are rare diseases, of which the management requires a rigorous approach: high-quality imaging, bacteriological sampling prior to antibiotic therapy whenever possible, and antibiotic treatment including metronidazole in addition to cefotaxime. Multidisciplinary collaboration, including infectious disease and neurosurgical advice, is always called for.