Management of bacterial central nervous system infections

Meropenem-Vaborbactam for the Treatment of Post-Neurosurgical Meningitis Caused by KPC Producer Klebsiella Pneumoniae: A Case Report and Review of the Literature

Meningitis and ventriculitis, due to carbapenem-resistant Enterobacterales, are frequently associated with significant morbidity and mortality. In the case of multi-drug-resistant pathogens, it is necessary to consider the limited susceptibility profile as well as the penetration of the antimicrobials into the brain. Limited data are available regarding the treatment of central nervous system infections caused by carbapenem-resistant Enterobacterales. We report a study of a patient treated with meropenem-vaborbactam in the case of post-neurosurgical meningitis due to carbapenemase-producing Klebsiella pneumoniae (CPKP).

Intrathecal or intraventricular antimicrobial therapy for post-neurosurgical Gram-negative bacillary meningitis or ventriculitis: a systematic review and meta-analysis

PURPOSE

Extensively-drug-resistant Gram-negative bacteria (XDR GNB)-related post-neurosurgical infection is closely related to mortality, which represents a major challenge for neurosurgeons. There is an urgent need to review and evaluate methods to reduce mortality.

METHODS

Both international and Chinese databases were searched independently from their inception to 15 June 2023. A meta-analysis was conducted using RevMan 5.4 to compare the efficacy and safety of intravenous (IV) treatment in combination with intrathecal or intraventricular (ITH/IVT) treatment with IV treatment alone for post-neurosurgical meningitis or ventriculitis due to GNB. Mortality, microbiological clearance and adverse events were considered as primary outcomes.

RESULTS

In total, 18 eligible studies involving 602 patients were included in the meta-analysis. The IV + ITH/IVT group was associated with significantly lower mortality (especially in the XDR GNB subgroup) and acceptable safety. In terms of microbiological clearance, a significant decrease was shown in the XDR GNB subgroup. Significant benefits were shown in laboratory parameters and clinical symptoms after patients were treated with ITH/IVT.

CONCLUSION

Additional ITH/IVT treatment may promote XDR GNB clearance and reduce mortality. In addition, ITH/IVT administration can improve clinical symptoms and cerebrospinal fluid indicators of patients with post-neurosurgical infections. Significantly, ITH/IVT treatment does not increase the incidence of adverse events at the recommended dose.

Economic impact of metagenomic next-generation sequencing versus traditional bacterial culture for postoperative central nervous system infections using a decision analysis mode: study protocol for a randomized controlled trial

IMPORTANCE

Diagnosing and treating postoperative central nervous system infections (PCNSIs) remains challenging due to the low detection rate and time-consuming nature of traditional methods for identifying microorganisms in cerebrospinal fluid. Metagenomic next-generation sequencing (mNGS) technology provides a rapid and comprehensive understanding of microbial composition in PCNSIs by swiftly sequencing and analyzing the microbial genome. The current study aimed to assess the economic impact of using mNGS versus traditional bacterial culture-directed PCNSIs diagnosis and therapy in post-neurosurgical patients from Beijing Tiantan Hospital. mNGS is a relatively expensive test item, and whether it has the corresponding health-economic significance in the clinical application of diagnosing intracranial infection has not been studied clearly. Therefore, the investigators hope to explore the clinical application value of mNGS detection in PCNSIs after neurosurgery.

Development and Validation of a Nomograph Model for Post-Operative Central Nervous System Infection after Craniocerebral Surgery

PURPOSE

A nomograph model of predicting the risk of post-operative central nervous system infection (PCNSI) after craniocerebral surgery was established and validated.

METHODS

The clinical medical records of patients after cranial surgery in Renmin Hospital of Wuhan University from January 2020 to September 2022 were collected, of whom 998 patients admitted to Shouyi Hospital District were used as the training set and 866 patients admitted to Guanggu Hospital District were used as the validation set. Lasso regression was applied to screen the independent variables in the training set, and the model was externally validated in the validation set.

RESULTS

A total of 1864 patients after craniocerebral surgery were included in this study, of whom 219 (11.75%) had PCNSI. Multivariate logistic regression analysis showed that age > 70 years, a previous history of diabetes, emergency operation, an operation time ≥ 4 h, insertion of a lumbar cistern drainage tube ≥ 72 h, insertion of an intracranial drainage tube ≥ 72 h, intraoperative blood loss ≥ 400 mL, complicated with shock, postoperative albumin ≤ 30 g/L, and an ICU length of stay ≥ 3 days were independent risk factors for PCNSI. The area under the curve (AUC) of the training set was 0.816 (95% confidence interval (95%CI), 0.773-0.859, and the AUC of the validation set was 0.760 (95%CI, 0.715-0.805). The calibration curves of the training set and the validation set showed p-values of 0.439 and 0.561, respectively, with the Hosmer-Lemeshow test. The analysis of the clinical decision curve showed that the nomograph model had high clinical application value.

CONCLUSION

The nomograph model constructed in this study to predict the risk of PCNSI after craniocerebral surgery has a good predictive ability.

Population Pharmacokinetics and Dosing Regimen Optimization of Linezolid in Cerebrospinal Fluid and Plasma of Post-operative Neurosurgical Patients

BACKGROUND

Linezolid is a valuable therapeutic option for infections of the central nervous system caused by multi-drug resistant Gram-positive pathogens. Data regarding linezolid pharmacokinetics in cerebrospinal fluid from post-operative neurosurgical patients have revealed wide inter-individual variability. The objectives of this study were to establish a population pharmacokinetic model for linezolid in plasma and cerebrospinal fluid, as well as to optimize dosing strategies in this susceptible population.

METHODS

This was a prospective pharmacokinetic study in post-operative neurosurgical patients receiving intravenous linezolid. Parallel blood and cerebrospinal fluid samples were collected and analyzed. The population pharmacokinetic modelling and Monte Carlo simulations were performed using the Phoenix NLME software.

RESULTS

A two-compartment model (central plasma and cerebrospinal fluid compartments) fit the linezolid data well, with creatinine clearance and serum procalcitonin as significant variables. Linezolid demonstrated highly variable penetration into cerebrospinal fluid, with a mean cerebrospinal fluid/plasma ratio of 0.53. A strong correlation was found between plasma trough concentration and cerebrospinal fluid exposure of linezolid. Based on simulation results, optimal dosage regimens stratified by various renal functions and inflammatory status were proposed.

CONCLUSION

A modeling and simulating strategy was employed in dose individualization to improve the efficacy and safety of linezolid treatment.

Acute Hydrocephalus Associated with Streptococcus anginosus Meningitis

Introduction

Meningitis-related acute hydrocephalus is rare, challenging to diagnose, and has a high mortality rate.

Case description

Here we describe the case of a 76-year-old patient diagnosed with bacterial meningitis who developed acute hydrocephalus and subsequently died.

Discussion

Although meningitis-related acute hydrocephalus is usually non-occlusive, occlusive hydrocephalus may also occur. Moreover, worsening hydrocephalus despite cerebrospinal fluid drainage should prompt a diagnosis of obstructive hydrocephalus. In such conditions, potential management strategies include ventriculoperitoneal shunt and endoscopic third ventriculostomy.

Conclusion

In patients with meningitis-related hydrocephalus, worsening despite appropriate antibiotic administration, treatment may be complicated by ventriculitis and obstructive hydrocephalus, which can be fatal. If intracranial pressure is not medically controlled, bilateral decompression craniectomy should be considered as a potential management strategy.

LEARNING POINTS

The extreme rarity of obstructive hydrocephalus caused by bacterial meningitis can lead to delayed diagnosis and treatment.Ventriculoperitoneal shunt and endoscopic third ventriculostomy are the indicated management strategies for early diagnosis of obstructive hydrocephalus.Bilateral decompression craniectomy may be an option in such cases.

Detection of multidrug-resistant Acinetobacter baumannii by metagenomic next-generation sequencing in central nervous system infection after neurosurgery: A case report

Background

Central nervous system (CNS) infection is one of the most serious complications after neurosurgery. Traditional clinical methods are difficult to diagnose the pathogen of intracranial infection. Due to recent advances in genomic approaches, especially sequencing technologies, metagenomic next-generation sequencing (mNGS) has been applied in many research and clinical settings.

Case presentation

Here, we report a case of CNS infection with Acinetobacter baumannii in a 15-year-old woman, who previously underwent surgery for recurrence of ependymoma in the fourth ventricle. On the eleventh postoperative day, the patient had a high fever and leukocytosis in the cerebrospinal fluid (CSF). mNGS using CSF rapidly and accurately identified the causative pathogen as A. baumannii with carbapenem resistance genes blaOXA-23 and blaOXA-51, which were confirmed by subsequent culture and susceptibility tests within 5 days. During the disease, mNGS, culture, and drug susceptibility testing were continued to monitor changes in pathogenic bacteria and adjust medication. At present, there are no case reports on to the use of mNGS for detecting pathogens in postoperative infection with ependymoma and guide medication.

Conclusion

mNGS has great advantages in pathogen identification and even pathogen resistance prediction. Multiple mNGS examinations during the course of the disease play an important role in the dynamic monitoring of pathogens.

Use of the FilmArray® Meningitis/Encephalitis panel to detect pathogenic microorganisms in cerebrospinal fluid specimens: a single-center retrospective study

OBJECTIVE

Meningitis and encephalitis are neurological emergencies requiring rapid diagnosis and treatment. The performance of the FilmArray® Meningitis/Encephalitis (ME) panel, a multiplex polymerase chain reaction test, and conventional methods for diagnosing meningitis and encephalitis was compared.

METHODS

This retrospective study assessed 20 patients diagnosed with meningitis or encephalitis according to clinical symptoms and laboratory examination findings between January 2018 and December 2019. The results of the FilmArray® ME panel were compared with those of conventional methods.

RESULTS

Pathogens were identified in 11 (55%) patients using the FilmArray® ME panel and in nine (45%) patients using conventional methods. The test identified herpes simplex virus type 1 in two patients, herpes simplex virus type 2 in one, varicella-zoster virus in four, Streptococcus pneumoniae in three, and Cryptococcus neoformans in one. Furthermore, additional pathogens were detected (n = 1, S. pneumoniae and n = 1, varicella-zoster virus). The median times to pathogen identification were 2 hours using the FilmArray® ME panel and 96 hours with conventional methods.

CONCLUSIONS

The sensitivity of the FilmArray® ME panel for rapidly detecting the most common pathogens was similar to that of conventional methods. Hence, this method could decrease the time to definitive diagnosis and treatment initiation.

Factors Affecting Development of Infection After Implantation of Ventriculoperitoneal Shunts in Patients with Posttraumatic Hydrocephalus

BACKGROUND

Patients with posttraumatic hydrocephalus (PTH) have a high incidence of infection after ventriculoperitoneal shunt (VPS). In this study, we investigated different risk factors affecting infection after VPS in PTH patients.

METHODS

Clinical data on PTH patients with VPS in Shaanxi Provincial People's Hospital from March 2012 to November 2020 were collected and analyzed retrospectively. We evaluated the relevance of patients' sex, age, cause of hydrocephalus, severity of hydrocephalus, types of hydrocephalus, hypertension, diabetes, decompressive craniectomy (DC), abdominal surgery, and duration of VPS surgery in the development of postoperative infection. Predictive values of different risk factors for the development of postoperative infection were analyzed using the receiver operating characteristic curve.

RESULTS

Shunt infection occurred in 38 patients (10.2% of cases). We found that patients >60 years of age with severe hydrocephalus, hypertension, diabetes, DC, and duration of surgery for VPS >60 minutes were at a significantly higher risk of developing an infection after VPS (P < 0.05). The area under the curve was used to predict shunt infection using age (0.611), severe hydrocephalus (0.589), hypertension (0.641), diabetes (0.657), DC (0.640), and duration of operation (0.600) as independent risk factors. The area under the curve of shunt infection predicted by whole index was 0.871.

CONCLUSIONS

Age, severe hydrocephalus, hypertension, diabetes, DC, as well as duration of operation for VPS (>60 minutes) were factors that significantly and independently correlated with the incidence of infection after VPS. The receiver operating characteristic curve that we have developed can predict the occurrence of shunt infection.

Risk Prediction of Central Nervous System Infection Secondary to Intraventricular Drainage in Patients with Intracerebral Hemorrhage: Development and Evaluation of a New Predictive Model Nomogram

BACKGROUND

Currently no reliable tools are available for predicting the risk of central nervous system (CNS) infections in patients with intracerebral hemorrhage after undergoing ventriculostomy drainage. The current study sought to develop and validate a nomogram to identify high-risk factors of CNS infection after ventriculomegaly drain placement for intracerebral hemorrhage.

METHODS

A total of 185 patients with intracerebral hemorrhage who underwent ventriculoperitoneal drainage were enrolled to the current study. Patients were divided into a CNS infection group (20 patients) and a non-CNS infection group (165 patients). The baseline data from both groups was used to develop and evaluate a model for predicting the likelihood of developing CNS infection after ventriculoperitoneal drain placement for intracerebral hemorrhage.

RESULTS

The finding showed that operative time, intraventricular drainage duration, postoperative temperature, white blood cell count in cerebrospinal fluid (CSF), neutrophils ratio in CSF, Red blood cell count in CSF, and glucose content in CSF were correlated with CNS infection. A nomogram for predicting the risk of CNS infection was constructed based on these variables. The c-index and the AUC of the ROC curve was 0.961, showing good discrimination. Clinical decision curve analysis indicated that the nomogram clinical application ranged between 1 and 100%. The clinical impact curve was generated to set with a threshold probability of 0.5.

CONCLUSION

The nomogram reported in the current study can be used by clinicians to identify patients likely to have secondary CNS infections, so that clinicians can better treat these patients at earlier stages.

Intrathecal/Intraventricular Colistin for Antibiotic-Resistant Bacterial CNS Infections in Pediatric Population: A Systematic Review

Central nervous system (CNS) infections constitute a life-threatening condition, especially in children. Treatment limitations exist for drug-resistant CNS bacterial infections. Inadequate CNS penetration and intravenous (IV) antibiotic treatment failure represent a major clinical challenge. However, patients with antibiotic-resistant bacterial CNS infections may benefit from intrathecal (IT) or intraventricular (IVT) colistin. The authors aimed to assess the safety and effectiveness of IT/IVT colistin therapy in the pediatric population, with or without other antibiotics, for the treatment of antibiotic-resistant CNS infections. A comprehensive literature search was conducted using the electronic databases of PubMed, Ovid, and Embase for relevant articles using the following terms: “Colistin”, “CNS infection”, and “Outcome”, as well as their combinations. The retrieved articles were filtered by age (Child), language (English), route of administration (IT/IVT), and species (Humans). The present systematic review comprised 20 articles that included 31 children (19; 61.2% were boys) with multidrug-resistant CNS infection. Their ages ranged from less than one month to 18 years (median: 9 months). Acinetobacter baumannii was the main causative organism in 22 patients (70.9%), and infection occurred mainly after neurosurgical interventions (83.8%). An external ventricular drain was inserted to administer colistin into the ventricular system in 29 cases (93.5%). The median duration for colistin therapy was 18 days. Twenty-three patients (74%) recovered, while five patients (16%) had residual disability, and three patients (10%) died. The authors concluded that IT/IVT colistin therapy is safe and effective as either the primary or adjunct treatment for antibiotic-resistant cases with CNS infection.

How safe is the use of intrathecal vancomycin?

AIM

Central Nervous System (CNS) infection after neurosurgical procedures is a severe complication with high morbidity rates and sometimes mortality. The present experimental study aims to investigate the biochemical and histopathological effects of vancomycin on neural tissues when applied to the cisterna magna.

MATERIAL AND METHOD

Wistar albino rats were randomly divided into four groups: Control (Group 1) and different vancomycin dose groups (groups 2, 3 and 4). In Group 1, 0.1 mL Cerebrospinal Fluid (CSF) was drained from the cisterna magna, and 0.1 mL 0.9% NaCI (normal saline) was administered into the subarachnoid space. In the study groups, 0.1 mL CSF was drained from the cisterna magna, 0.1 mg/day (Group 2), 0.2 mg/day (Group 3) and 0.4 mg/day (Group 4) vancomycin were administered into the subarachnoid space for seven days, and all rats were sacrificed on 8th day. Serum Superoxide dismutase (SOD) and Catalase (CAT) levels were measured. Histopathologic and immunohistochemical analyses were conducted.

RESULT

The findings showed that the administration of 0.2 and 0.4 mg/kg doses had significant differences in SOD and CAT activity compared to the controls (p<0.05). These vancomycin doses also induced the apoptotic process, and the enzyme activity results correlated with immunohistochemical results.

CONCLUSION

Dose-related neurotoxicity of intrathecal vancomycin was shown at the cellular level. The importance of dose regulation of intrathecal vancomycin has come into view. To our knowledge, this is the first study in the literature that has investigated the neurotoxic effects of vancomycin.

Brain Abscess in the Current Decade (2010–2019) in India—A Review

Brain abscess outcomes have improved in recent years due to advancements in cranial imaging, microbiological techniques, minimally invasive neurosurgical procedures, and effective antibiotic treatments. However, the incidence of brain abscess remains unchanged in developing countries. We searched PubMed and Google Scholar for references using the key words “brain abscess” and “India” and reviewed both retrospective and prospective studies published in peer-reviewed journals in the current decade to understand the present status. The review shows that the patients’ ages, the predominance of male patients, the symptoms and locations of brain abscesses, and the types of bacteria associated with them have remained unchanged over the past decade. The most common predisposing condition in recent years has been chronic suppurative otitis media with a mortality rate of 7 to 10%. Middle ear infection is often neglected and not treated aggressively in Asian countries. It requires multidisciplinary treatment strategies to address the primary source of infection and better health awareness to prevent the development of brain abscess.

Transpeptidation-mediated single-particle imaging assay for sensitive and specific detection of sortase with dark-field optical microscopy

Transpeptidation of surface proteins catalyzed by the transpeptidase sortase plays a critical role in the infection process of Gram-positive pathogen. Monitoring sortase activity and screening its inhibitors are of great significance to fundamental understanding of the infection mechanism and pharmaceutical development. Herein, we developed a digital single-particle imaging method to quantify sortase A (SrtA) activity based on transpeptidation-mediated assembly and enumeration of gold nanoparticles (GNPs). The assay utilizes two peptide stands, in which one has the SrtA recognition sequence LPXTG motif while the other carries an oligoglycine nucleophile at the one end and a biotin group at the other. The presence of SrtA enables the ligation of two peptides and allows for the immobilization of streptavidin-functionalized GNPs. Thus, SrtA activity can be quantified by imaging and enumeration of the surface-assembled GNPs at the single-particle level via dark-field microscopy. The single-particle method was highly sensitive to SrtA activity with a low detection limit of 7.9 pM and a wide linear dynamic range from 0.05 to 50 nM. Besides detection of SrtA in complex biological samples such as Gram-positive pathogen lysates, the proposed method was also successfully applied to estimate the half-maximal inhibitory concentration (IC₅₀) values of SrtA inhibitors (curcumin, berberine hydrochloride and quercetin). The present method, combining single-GNP counting and dark-field imaging, provides a facile and novel analytical tool for SrtA activity and its inhibitor screening.

Delays in antibiotic redosing: Association with inpatient mortality and risk factors for delay

OBJECTIVE

Although timely administration of antibiotics has an established benefit in serious bacterial infection, the majority of studies evaluating antibiotic delay focus only on the first dose. Recent evidence suggests that delays in redosing may also be associated with worse clinical outcome. In light of the increasing burden of boarding in Emergency Departments (ED) and subsequent need to redose antibiotic in the ED, we examined the association between delayed second antibiotic dose administration and mortality among patients admitted from the ED with a broad array of infections and characterized risk factors associated with delayed second dose administration.

METHODS

We performed a retrospective cohort study of patients admitted through five EDs in a single healthcare system from 1/2018 through 12/2018. Our study included all patients, aged 18 years or older, who received two intravenous antibiotic doses within a 30-h period, with the first dose administered in the ED. Patients with end stage renal disease, cirrhosis and extremes of weight were excluded due to a lack of consensus on antibiotic dosing intervals for these populations. Delay was defined as administration of the second dose at a time-point greater than 125% of the recommended interval. The primary outcome was in-hospital mortality.

RESULTS

A total of 5605 second antibiotic doses, occurring during 4904 visits, met study criteria. Delayed administration of the second dose occurred during 21.1% of visits. After adjustment for patient characteristics, delayed second dose administration was associated with increased odds of in-hospital mortality (OR 1.50, 95%CI 1.05-2.13). Regarding risk factors for delay, every one-hour increase in allowable compliance time was associated with a 18% decrease in odds of delay (OR 0.82 95%CI 0.75-0.88). Other risk factors for delay included ED boarding more than 4 h (OR 1.47, 95%CI 1.27-1.71) or a high acuity presentation as defined by emergency severity index (ESI) (OR 1.54, 95%CI 1.30-1.81 for ESI 1-2 versus 3-5).

CONCLUSIONS

Delays in second antibiotic dose administration were frequent in the ED and early hospital course, and were associated with increased odds of in-hospital mortality. Several risk factors associated with delays in second dose administration, including ED boarding, were identified.

Serum levels of neurofilament light chain, neuron-specific enolase and S100 calcium-binding protein B during acute bacterial meningitis: a prospective cohort study

PURPOSE

Acute bacterial meningitis (ABM) is a severe disease with an overall poor outcome. Neurofilament (NFL) has shown to be a promising biomarker of neuroaxonal injury in various neurological disorders but has not been investigated in ABM. The aims of this study were (i) to obtain a temporal profile of NFL, neuron-specific enolase (NSE) and S100B in serum during ABM, and (ii) to evaluate their use as biomarkers of severity (Glasgow coma score) and prognosis (Glasgow Outcome Score, GOS and death) in severe ABM.

METHODS

Fifteen adults with severe community-acquired ABM who were admitted to the intensive care unit (ICU) and fulfilled the inclusion criteria were included. Lumbar puncture and blood tests were performed on admission, and blood tests were performed three times daily during the ICU stay. GOS was obtained day 30.

RESULTS

Serum NFL was significantly elevated in ABM patients compared to healthy controls, both at admission and throughout the observation period (p < .01). NFL increased significantly from day 1 up to day 3-6 (p < .0001), peaking day 6. NSE increased significantly from admission up to day 3 (p < .01). At day 5-6, the serum values were not significantly different from values at admission. The highest median serum value of S100B was observed at admission (0.10 µg/L, IQR 0.06-0.14), significantly decreasing day 4-6 (p < .05). None of the investigated biomarkers revealed significant correlation with severity and prognosis.

CONCLUSION

This study represents a first clinical observation of the temporal profile of NFL in serum, in severe ABM. No correlation with severity or prognosis.

Diagnosis of Streptococcus suis Meningoencephalitis with metagenomic next-generation sequencing of the cerebrospinal fluid: a case report with literature review

Background

Streptococcus suis meningoencephalitis is a zoonotic disease that mostly infects slaughterhouse workers. Rapid diagnosis of Streptococcus suis meningoencephalitis is critical for effective clinical management of this condition. However, the current diagnostic techniques are not effective for early diagnosis of this condition. To the best of our knowledge, the use of cerebrospinal fluid metagenomic next generation sequencing in the diagnosis of Streptococcus suis meningoencephalitis has been rarely reported.

Case presentation

Here, we report a case of Streptococcus suis meningoencephalitis in a 51-year-old female patient. The patient had a history of long-term contact with pork and had a three-centimeter-long wound on her left leg prior to disease onset. Conventional tests, including blood culture, gram staining and cerebrospinal fluid culture, did not reveal bacterial infection. However, Streptococcus suis was detected in cerebrospinal fluid using metagenomic next generation sequencing.

Conclusions

Metagenomic next generation sequencing is a promising approach for early diagnosis of central nervous system infections. This case report indicates that cases of clinical meningeal encephalitis of unknown cause can be diagnosed through this method.

Receptor Blockade: A Novel Approach to Protect the Brain From Pneumococcal Invasion

Background

Pneumococci are the major cause of bacterial meningitis globally. To cause meningitis pneumococci interact with the 2 endothelial receptors, polymeric immunoglobulin receptor (pIgR) and platelet endothelial cell adhesion molecule (PECAM-1), to penetrate the blood-brain barrier (BBB) and invade the brain.

Methods

C57BL/6 mice were infected intravenously with bioluminescent pneumococci, and treated with ceftriaxone (1 hour postinfection) and anti-pIgR and PECAM-1 antibodies (1 or 5 hours postinfection), then monitored for 5 and 10 days. Bacterial brain invasion was analyzed using IVIS imaging and bacterial counts.

Results

Ceftriaxone, given early after pneumococcal challenge, cleared pneumococci from the blood but not from the brain. After combining ceftriaxone with receptor blockade, using anti-pIgR and PECAM-1 antibodies, we found 100% survival after 5 and 10 days of infection, in contrast to 60% for ceftriaxone alone. Combined antibiotic and antibody treatment resulted in no or few viable bacteria in the brain and no microglia activation. Antibodies remained bound to the receptors during the study period. Receptor blockade did not interfere with antibiotic permeability through the BBB.

Conclusions

We suggest that adjunct treatment with pIgR and PECAM-1 antibodies to antibiotics may prevent pneumococcal meningitis development and associated brain damages. However, further evaluations are required.

Multiple brain abscesses treated by extraction of the maxillary molars with chronic apical lesion to remove the source of infection

Background

Brain abscess is a life-threatening condition that occurs due to complications during a neurosurgical procedure, direct cranial trauma, or the presence of local or distal infection. Infection in the oral cavity can also be considered a source of brain abscess.

Case presentation

A 45-year-old male patient was transported with brain abscess in the subcortical white matter. Navigation-guided abscess aspiration and drainage was performed in the right mid-frontal lobe, but the symptoms continued to worsen after the procedure. A panoramic radiograph showed alveolar bone resorption around the maxillary molars. The compromised maxillary molars were extracted under local anesthesia, and antibiotics were applied based on findings from bacterial culture. A brain MRI confirmed that the three brain abscesses in the frontal lobe were reduced in size, and the patient’s symptoms began to improve after the extractions.

Conclusion

This is a rare case report about multiple uncontrolled brain abscesses treated by removal of infection through the extraction of maxillary molars with odontogenic infection. Untreated odontogenic infection can also be considered a cause of brain abscess. Therefore, it is necessary to recognize the possibility that untreated odontogenic infection can lead to serious systemic inflammatory diseases such as brain abscess. Through a multidisciplinary approach to diagnosis and treatment, physicians should be encouraged to consider odontogenic infections as a potential cause of brain abscesses.

Pediatric meningitis due to Neisseria meningitidis, Streptococcus pneumoniae and Group B Streptococcus in Tijuana, Mexico: active/prospective surveillance, 2005-2018

Introduction

In Mexico, Neisseria meningitidis is considered to be a rare cause of bacterial meningitis (BM), however, one national publication using active surveillance has suggested the opposite. Group B Streptococcus (GBS) is also considered to be infrequent in young infants as a cause of BM in central Mexico. Streptococcus pneumoniae vaccination using the 13-valent conjugate vaccine (PCV13) started in our region in May 2012. We focused our research on whether N. meningitidis and GBS are important causes of BM, and to examine the effectiveness of PCV13 on pneumococcal BM.

Methods

From October 2005 to September 2018, active/prospective surveillance looking for all patients admitted with suspected BM <16 years of age was performed at the Tijuana, Mexico, General Hospital. Tijuana, Mexico to San Diego, Unites States of America (USA), is the most transited border in the world. Isolation of pathogens was by either conventional culture or Real Time-polymerase chain reaction (RT-PCR), all patients were followed during and 3 months after discharge, and a descriptive analysis was performed. The effectiveness of PCV13 was determined by comparing the proportion of cases per month on pneumococcal BM before and after its implementation.

Results

There were 86 confirmed BM cases. N. meningitidis was the leading cause (60.5%, and 61.5% caused by serogroup C), followed by S. pneumoniae (18.6%). PCV13 effectiveness on pneumococcal BM was of 64.3% and was associated with the disappearance of serotype 19A. A total of 22 infants <3 months old had BM; GBS was the leading cause at this age group (27.3%), followed by N. meningitidis (22.7%). The overall mortality was 24%.

Conclusions

BM by N. meningitidis is endemic in Tijuana, Mexico, and meningococcal vaccination should be seriously considered in the region. PCV13 is currently showing high effectiveness on pneumococcal BM, and we need to continue active surveillance to see whether maternal screening/prophylaxis for GBS should also be introduced in the region.

Introduction to Neuroimaging

Primary care physicians are often tasked with evaluating neurologic symptoms, and imaging plays a critical role in neurologic diagnoses. Neuroradiology routinely employs advanced imaging modalities, and hence, determination of the appropriate imaging test and interpretation of findings in the clinical context can understandably be overwhelming. In this review article, we introduce resources that can guide physicians in the selection of neuroimaging tests and summarize guidelines on contrast agent administration. Key concepts on imaging techniques and terminology are reviewed, as is relevant for the primary care physician. We then present an overview of the typical imaging manifestations of brain pathologies, including stroke, traumatic injuries, infections, demyelinating and neurodegenerative processes, and neoplasms. Spine imaging is often considered for the evaluation of degenerative, infectious, or neoplastic etiologies, and the typical imaging findings in these scenarios are also summarized.

DNA repair protein APE1 is involved in host response during pneumococcal meningitis and its expression can be modulated by vitamin B6

Background

The production of reactive oxygen species (ROS) during pneumococcal meningitis (PM) leads to severe DNA damage in the neurons and is the major cause of cell death during infection. Hence, the use of antioxidants as adjuvant therapy has been investigated. Previous studies have demonstrated the possible participation of apurinic/apyrimidinic endonuclease (APE1) during PM. The aims of this study were to investigate the APE1 expression in the cortical and hippocampal tissues of infant Wistar rats infected with Streptococcus pneumoniae and its association with cell death and understand the role of vitamin B6 (vitB6) as a protective factor against cell death.

Methods

APE1 expression and oxidative stress markers were analyzed at two-time points, 20 and 24 h post infection (p.i.), in the cortex (CX) and hippocampus (HC) of rats supplemented with vitB6. Statistical analyses were performed by the nonparametric Kruskal–Wallis test using Dunn’s post test.

Results

Our results showed high protein levels of APE1 in CX and HC of infected rats. In the CX, at 20 h p.i., vitB6 supplementation led to the reduction of expression of APE1 and apoptosis-inducing factor, while no significant changes in the transcript levels of caspase-3 were observed. Furthermore, levels of carbonyl content and glutamate in the CX were reduced by vitB6 supplementation at the same time point of 20 h p.i.. Since our data showed a significant effect of vitB6 on the CX at 20 h p.i. rather than that at 24 h p.i., we evaluated the effect of administering a second dose of vitB6 at 18 h p.i. and sacrifice at 24 h p.i.. Reduction in the oxidative stress and APE1 levels were observed, although the latter was not significant. Although the levels of APE1 was not significantly changed in the HC with vitB6 adjuvant therapy, vitB6 supplementation prevented the formation of the truncated form of APE1 (34 kDa) that is associated with apoptosis.

Conclusions

Our data suggest that PM affects APE1 expression, which can be modulated by vitB6. Additionally, vitB6 contributes to the reduction of glutamate and ROS levels. Besides the potential to reduce cell death and oxidative stress during neuroinflammation, vitB6 showed enhanced effect on the CX than on the HC during PM.