Treatment Of Meningitis Research Articles

Population pharmacokinetic modeling of ceftriaxone in cerebrospinal fluid in children: should we be using once- or twice-daily dosing for meningitis?

Guidelines for bacterial meningitis in children recommend intravenous ceftriaxone 50 mg/kg (max 2 g) twice daily (BD) or 100 mg/kg (max 4 g) once daily (OD), leaving the decision regarding the dose frequency to the prescriber. We investigated the cerebrospinal fluid (CSF) penetration of ceftriaxone to evaluate whether one dosing regimen is superior. Unbound ceftriaxone concentrations were measured in serum and CSF samples from children aged 0-18 years treated with ceftriaxone if there was a sample remaining after clinical tests were performed. A serum-CSF population pharmacokinetic model was developed using non-linear mixed-effects modeling. The once- and twice-daily dosing regimens were simulated, and the probability of target attainment (PTA) was determined for maintaining a CSF concentration above a minimum inhibitory concentration (MIC) of 1 mg/L for common meningitis pathogens and 4 mg/L for Staphylococcus aureus for 100% of the dosing interval. Sixteen serum and 87 CSF samples were collected from 98 children (age range 0.1-18.5 years). The final two-compartment serum-CSF model included a renal maturation function with weight scaling on clearance and volume of distribution. The estimated serum:CSF uptake was 20.1%. For MIC 1 mg/L, the 24 h PTA was higher for OD (88%) compared with BD (53%) dosing, although both achieved a 100% PTA at steady state. For S. aureus (MIC 4 mg/L), neither dosing regimen was sufficient. Our findings support the use of a 100 mg/kg once daily regimen for empirical treatment of bacterial meningitis due to earlier achievement of the pharmacodynamic target. Neither dosing regimen was adequate for S. aureus meningitis.

Intrathecal Tigecycline in the Treatment of Hospital-Acquired Meningitis: A Review of Four Cases.

Objectives: Carbapenem-resistant A. baumannii is a common cause of nosocomial meningitis, and it presents a challenge in terms of treatment because of limited therapeutic options. Intravenous tigecycline has been considered a potential salvage therapy against multi-drug-resistant Acinetobacter baumannii. However, its effectiveness is limited by its poor ability to cross the blood-brain barrier. As an alternative treatment option, intrathecal tigecycline has shown promise with its minimal side effects and high concentration in cerebrospinal fluid. Methods: In this report, we present a series of four cases infected with multi-drug-resistant A. baumannii following neurosurgery and treated with intrathecal tigecycline, including antimicrobial therapy. Results: The rate of successful microbiological response was 2 out of 3 cases (66%) in whom microbiological response could be tested anytime during the intrathecal therapy, whereas the 30-day survival rate after treatment completion was ¼ (25%). Conclusion: Although intrathecal tigecycline treatment has shown relative efficacy in achieving microbiological response, its impact on overall survival is still uncertain. Further studies involving larger groups of patients are necessary to evaluate the outcomes of intrathecal tigecycline therapy.

Epidemiology, microbiology and antibiotic treatment of bacterial and fungal meningitis among very preterm infants in China: a cross-sectional study

ObjectiveNeonatal meningitis significantly contributes to neonatal morbidity and mortality, yet large-scale epidemiological data in developing countries, particularly among very preterm infants (VPIs), remain sparse. This study aimed to describe the...

Management of Otogenic Meningitis: A Proposal for Practical Guidelines from a Multicenter Experience with a Systematic Review.

Background: Otogenic meningitis represents the most common and life-threatening complication of infective middle ear diseases. However, no guidelines are available to describe the optimal management strategy and the role of surgical intervention. Methods: A six-year multicenter retrospective study on consecutive patients treated for otogenic meningitis caused by acute otitis and re-exacerbation of chronic otitis at the University Hospital of Verona and Modena was performed, and a systematic review regarding acute otitis media-related meningitis in accordance with the PRISMA 2020 statement was then conducted. Results: From the clinical chart analysis, 16 patients with surgical indications according to our decision-making flow chart were reviewed, with most of them undergoing surgery within 7 days of admission (n = 13, 81%). The systematic review ultimately utilized 24 studies (16 case reports and 8 case series) published between 1990 and 2023, with the overall analysis involving a total of 181 patients. Conclusion: The primary treatment for acute bacterial meningitis relies on antibiotic therapy, with surgical intervention being employed in the event of complications and when the initial treatment is not effective within 48 h. The objective of surgery is to sterilize the tympanic and mastoid cavity, thereby eradicating the suspected infective foci and managing any eventual intracranial complications.

Bacterial Meningitis Following Aneurysmal Subarachnoid Hemorrhage and Its Association with Cerebral Vasospasm.

Aneurysmal subarachnoid hemorrhage (aSAH) is a critical condition with high in-hospital mortality rates. Delayed cerebral ischemia (DCI), a secondary complication associated with aSAH, can also contribute to morbidity and mortality. Although draining the hematoma from the subarachnoid space has been considered effective in preventing DCI, the placement of a drainage system could increase the risk of bacterial meningitis and ventriculitis. This study aimed to examine the association between meningitis following aSAH and the occurrence of DCI, focusing on the role of cerebral vasospasm. Patients who underwent endovascular coiling or surgical clipping for aSAH from April 2001 to March 2022 were included in this study, while those who did not undergo postoperative drainage were excluded. The patient's clinical characteristics, treatment modalities, and outcomes were then analyzed, after which logistic regression was used to assess the odds ratios (OR) for DCI. A total of 810 patients with aSAH were included in this study. Meningitis following aSAH was identified as an independent factor associated with DCI (odds ratio 5.0 [95% confidence intervals (CI) 2.3-11]). Other significant factors were female sex (odds ratio 1.5 [95% CI 0.89-2.5]) and surgical clipping (odds ratio 2.1 [95% CI 1.3-3.4]). This study demonstrated a significant association between meningitis following aSAH and the development of DCI, suggesting that the inflammatory environment associated with meningitis may contribute to cerebral vasospasm. Early recognition and treatment of meningitis in patients with aSAH could reduce the risk of DCI and improve patient outcomes.

Melatonin as a Treatment Option for Bacterial Meningitis – A Comprehensive Review

Bacterial meningitis (BM) is a global acute infectious central nervous system (CNS) illness that leaves 50% of survivors with long-term significant consequences. Acute bacterial meningitis is more common in low-resource areas than in high-resource areas. Bacterial survival and multiplication in the circulation, increased permeability of the blood brain barrier (BBB), oxidative stress, and an overactive inflammatory response in the CNS are all involved in the pathogenesis of BM. Because drug-resistant bacteria make treatment for meningitis more difficult, the vaccination has been confined to a few serotypes, and the BM morbidity rate remains high. With recent advances in neurology, there is hope for medication supplements that can successfully prevent and cure BM. Several in vivo and in vitro researches have been conducted to better understand how melatonin affects BM. Melatonin is primarily produced in the pineal gland and has the ability to cross the BBB. Melatonin and its metabolite have been found to be efficient antioxidants and anti-inflammatories, suggesting that they might be used to prevent and treat BM. Melatonin can protect the brain against bacterial meningitis through a variety of mechanisms, including immunological response, antibacterial capabilities, BBB integrity protection, free radical scavenging, anti-inflammation, signalling pathways, and gut microbiota. This paper highlights melatonin's primary neuroprotective processes and investigates prospective preventative and therapy strategies for BM nerve damage. Keywords: Bacterial Meningitis, Neuron Injury, Melatonin, Neuroprotection

Neuroprotective effects of ulinastatin on Escherichia coli meningitis rats through inhibiting PKCα phosphorylation and reducing zonula occludens-1 degradation

Ulinastatin, a broad-spectrum inflammatory inhibitor widely employed in the management of severe pancreatitis and sepsis, has not been extensively investigated for its therapeutic potential in bacterial meningitis. This study aims to assess the neuroprotective effects of ulinastatin on bacterial meningitis and elucidate its underlying mechanism. The rat model of bacterial meningitis was established by intracerebral injection of Escherichia coli. 3-week-old SD rats were randomly divided into 5 groups with 8 rats in each group, including control group, E.coli group, E.coli + UTI group (ulinastatin 50000IU/kg), E.coli + UTI + PMA group (ulinastatin 50000IU/kg + PMA 200 ug/kg), and E.coli + PMA group(PMA 200 ug/kg). Behavioral changes were assessed by Loeffler neurobehavioral score. Histomorphologic changes and apoptosis were assessed by hematoxylin and eosin staining, Nissl staining and TUNEL staining. Immunohistochemistry and immunofluorescence and western blotting were used to detect the expression levels of zonula occludens-1 (ZO-1) and phosphorylation protein kinase C (PKCα).It was found that ulinastatin treatment in Escherichia coli meningitis rats improved neurological function, alleviated meningeal inflammatory infiltration, reduced neuronal death, promoted the integrity of the blood–brain barrier structure. Moreover, phorbol myristate acetate (PMA, a protein kinase C activator), blocked the effective action of ulinastatin. These findings suggest that ulinastatin had neuroprotective effects on bacterial meningitis by inhibiting PKCα phosphorylation and reducing ZO-1 degradation, demonstrating that ulinastatin may be a promising strategy in the treatment of bacterial meningitis.

Update on diagnosis and treatment of fungal meningitis: lessons from recent outbreaks.

Recently, fungal meningitis outbreaks have occurred in association with neuraxial and epidural anesthesia in immunocompetent patients. Herein, we describe the course of those outbreaks, their diagnosis, treatment, prognosis, and lessons learned. Two outbreaks of Fusarium solani meningitis during 2022-2023 were associated with epidural anesthesia in two distant cities in Mexico (Durango and Matamoros). The initial etiological agent identification was delayed due to insensitivity of cultures. A Fusarium solani qPCR was validated and positive in 38% cerebrospinal fluid (CSF) samples from Durango, while BD-Glucan allowed early diagnosis of the index case in Matamoros. Antifungal treatment with voriconazole and liposomal amphotericin B (L-AmB) was recommended. Overall mortality was 51%. Once the cause was confirmed, some patients received fosmanogepix. Fungal meningitis outbreaks due to filamentous fungi are usually associated with direct epidural inoculation. They result in severe presentations and high mortality. Early diagnosis should be suspected, BD-Glucan CSF testing screening is recommended. Aggressive antifungal treatment based on antifungal susceptibility testing should be administered as early as possible. The advent of molecular diagnostic methods and new antifungal drugs may allow for timely diagnosis and treatment, increasing the chances of survival.

Design of RNA Polymerase Inhibitors as Therapeutics for Tuberculous Meningitis.

Tuberculosis is an infectious disease caused by Mycobacterium tuber-culosis. The current treatment protocols for pulmonary tuberculosis are quite effective, even though the treatment requires 3-6 months. The current treatment protocols for extrapulmonary tuberculosis are based on the same drugs that are used for pulmonary tuberculosis. However, the success rates are much lower for certain types of extrapulmonary tuberculosis, such as tubercu-lous meningitis. Tuberculous meningitis is one of the very few diseases attributable to bacteria that have a very high short-term mortality rate among diagnosed patients, even after treatment with antibiotics that are effective for pulmonary tuberculosis. For example, rifampicin is highly effective for the treatment of pulmonary tuberculosis, but its effectiveness for the treatment of tuberculous meningitis is much lower. The reason for the lower effectiveness of rifampicin against tuberculous meningitis is that it has low Blood-Brain Barrier (BBB) permeability, which results in lower concentrations of the drug at the required sites in the central nervous system. In this work, ligands having increased BBB permeability and pharmacokinetic and pharmacodynamic properties, either similar to or better than that of rifampicin, have been de-signed. The BBB permeability of the designed molecules was assessed by using pkCSM, a ma-chine-learning model. Pharmacokinetic properties, drug-likeness, and synthesizability were as-sessed by using SWISS-MODEL. The binding affinity of the designed drugs was assessed by using AutoDock Vina. A customized scoring function, StWN score, was used for a quantitative weighted assessment of all the properties of interest to rank the designed molecules. In this study, drug-like ligands have been designed that have been predicted to have high BBB permeability as well as high affinity for RNA polymerase  ofMycobacterium tuberculosis. The best ligands generated by the tools employed were selected as potential drugs to address the current need for better options for the treatment of tuberculous meningitis.

Implementation of single high-dose liposomal amphotericin B based induction therapy for treatment of HIV-associated cryptococcal meningitis in Uganda: a comparative prospective cohort study.

In 2022, the World Health Organization (WHO) recommended a single 10mg/kg dose of liposomal amphotericin B in combination with 14 days of flucytosine and fluconazole (AMBITION-cm regimen) for induction therapy of HIV-associated cryptococcal meningitis, based on the results of the multisite AMBITION-cm trial. We evaluated outcomes after real-world implementation of this novel regimen in Uganda. We enrolled Ugandan adults with cryptococcal meningitis into an observational cohort receiving the AMBITION-cm regimen with therapeutic lumbar punctures in routine care during 2022-2023. We compared 10-week survival and CSF early fungicidal activity with the outcomes observed in the AMBITION-cm clinical trial conducted at the same sites. During 2022-2023, 179 adults were treated with the AMBITION-cm regimen via routine care and compared to the 171 adults randomized to the AMBITION-cm trial interventional arm in Uganda from 2018-2021. No significant difference in 10-week survival occurred between the observational cohort (68.6%; 95%CI 61.6%-76.3%) and AMBITION-cm trial participants in the intervention arm (71.7%; 95%CI 65.2%-78.8%; absolute risk difference = -3.1%; 95%CI -13.1% to 6.9%; p=.61). Early fungicidal activity did not differ (0.42 vs 0.39 log10CFU/mL/day; p=.80) between groups. Among observational cohort participants discharged alive initially and for whom follow up data were available, the incidence of re-hospitalizations due to persistently elevated intracranial pressure was 2.8% (4/144). The AMBITION-cm regimen for cryptococcal meningitis resulted in similar outcomes as observed in the AMBITION-cm clinical trial when implemented in routine care. Intracranial pressure management during hospitalization and awareness after discharge are key components of optimizing outcomes.

The diagnostic potential of urine in paediatric patients undergoing initial treatment for tuberculous meningitis

Tuberculous meningitis (TBM)—the extrapulmonary form of tuberculosis, is the most severe complication associated with tuberculosis, particularly in infants and children. The gold standard for the diagnosis of TBM requires cerebrospinal fluid (CSF) through lumbar puncture—an invasive sample collection method, and currently available CSF assays are often not sufficient for a definitive TBM diagnosis. Urine is metabolite-rich and relatively unexplored in terms of its potential to diagnose neuroinfectious diseases. We used an untargeted proton magnetic resonance (1H-NMR) metabolomics approach to compare the urine from 32 patients with TBM (stratified into stages 1, 2 and 3) against that from 39 controls in a South African paediatric cohort. Significant spectral bins had to satisfy three of our four strict cut-off quantitative statistical criteria. Five significant biological metabolites were identified—1-methylnicotinamide, 3-hydroxyisovaleric acid, 5-aminolevulinic acid, N-acetylglutamine and methanol—which had no correlation with medication metabolites. ROC analysis revealed that methanol lacked diagnostic sensitivity, but the other four metabolites showed good diagnostic potential. Furthermore, we compared mild (stage 1) TBM and severe (stages 2 and 3) TBM, and our multivariate metabolic model could successfully classify severe but not mild TBM. Our results show that urine can potentially be used to diagnose severe TBM.

Dynamic PET reveals compartmentalized brain and lung tissue antibiotic exposures of tuberculosis drugs

Tuberculosis (TB) remains a leading cause of death, but antibiotic treatments for tuberculous meningitis, the deadliest form of TB, are based on those developed for pulmonary TB and not optimized for brain penetration. Here, we perform first-in-human dynamic 18F-pretomanid positron emission tomography (PET) in eight human subjects to visualize 18F-pretomanid biodistribution as concentration-time exposures in multiple compartments (NCT05609552), demonstrating preferential brain versus lung tissue partitioning. Preferential, antibiotic-specific partitioning into brain or lung tissues of several antibiotics, active against multidrug resistant (MDR) Mycobacterium tuberculosis strains, are confirmed in experimentally-infected mice and rabbits, using dynamic PET with chemically identical antibiotic radioanalogs, and postmortem mass spectrometry measurements. PET-facilitated pharmacokinetic modeling predicts human dosing necessary to attain therapeutic brain exposures. These data are used to design optimized, pretomanid-based regimens which are evaluated at human equipotent dosing in a mouse model of TB meningitis, demonstrating excellent bactericidal activity without an increase in intracerebral inflammation or brain injury. Importantly, several antibiotic regimens demonstrate discordant activities in brain and lung tissues in the same animal, correlating with tissue antibiotic exposures. These data provide a mechanistic basis for the compartmentalized activities of antibiotic regimens, with important implications for developing treatments for meningitis and other infections in compartments with unique antibiotic penetration.

Efficacy and safety of first-line anti-tuberculosis drugs combined with Linezolid for the treatment of pediatric tuberculous meningitis in real-word practice

Objective: To evaluate the efficacy and safety of first-line anti-tuberculosis (TB) drugs combined with linezolid in treatment of children with tuberculous meningitis (TBM). Methods: A retrospective cohort study design was performed. Eight-nine Children diagnosed as TBM during January 1st 2016 and December 31st 2023 in Department of Infectious Disease, Children's Hospital of Chongqing Medical University were enrolled in the study. According to different treatment regimens, children were divided into a group of first-line anti-tuberculous drugs (isoniazid, rifampicin, pyrazinamide, ethambutol (HRZE)) and a group of HRZE and linezolid combination (HRZEL). The efficacy and safety of the 2 regimens were compared and the relationship between linezolid drug concentration and adverse reactions were analyzed. Comparisons between groups were performed using χ2 test and Mann-Whitney U test. Results: The 89 children with TBM included 53 males and 36 females with an onset age of 4.6 (1.4, 9.6) years. There were 27 cases in the HZREL group and 62 cases in the HRZE group. Before treatment, positive rate of interferon-gamma release assays (IGRA) in HRZEL group was lower than that in HRZE group (64% (16/25) vs.92% (55/60), χ2=9.82, P<0.05), but protein level of cerebrospinal fluid (CSF) was higher than that in HRZE group (1.2 (1.0, 2.0) vs.0.8 (0.4,1.4) g/L, Z=0.32, P<0.05). By the end of the intensive phase, there were no significant differences of rates of CSF improvement and etiology negativity between HRZEL group and HRZE group (both P>0.05).The 44 TBM children with high CSF protein (>1 g/L) included 25 males and 19 females with an onset age of 6.7 (3.0, 11.8) years. There were 21 cases in the HZREL group and 23 cases in the HRZE group accordingly. Before treatment, there were no significant differences of positive rate of IGRA test and CSF protein level between the 2 groups (62% (13/21) vs. 87% (20/23), 1.7 (1.1, 2.2) vs. 1.5 (1.2, 1.9) g/L, χ2=3.67, Z=0.23, both P>0.05). There were no significant differences in CSF indicators, etiology negativity or imaging remission between the two groups by the end of intensive phase (all P>0.05). Higher frequencies of granulocytopenia, gastrointestinal symptoms as well as withdrawal or change of drugs were found in HRZEL group when compared to those in HRZE group (44% (12/27) vs. 19% (12/62), 7% (2/27) vs. 0, 33% (9/27) vs. 3% (2/62), χ2=6.01, 4.70, 15.74, all P<0.05). Conclusions: The efficacy of HRZEL regimen is similar to conventional HRZE regimen in children with TBM, but with higher adverse effect. Prudentially evaluating the pros and cons of linezolid in the usage of drug-susceptible TB and carefully monitoring of linezolid associated adverse effects is suggested.

Efficacy of Antibiotic Regimens for Meningitis in Young Infants Aged 0-59 Days: A Systematic Review.

Meningitis is associated with high mortality risk in young infants, yet the optimal treatment regimen is unclear. To systematically evaluate the efficacy of antibiotic regimens to treat meningitis in young infants aged 0 to 59 days on critical clinical outcomes. MEDLINE, Embase, CINAHL, WHO Global Index Medicus, and Cochrane Central Registry of Trials. We included randomized controlled trials (RCTs) of young infants with meningitis (population) comparing the efficacy of antibiotic regimens (interventions) with alternate regimens (control) on clinical outcomes. We extracted data on study characteristics and assessed risk of bias in duplicate. Grading of Recommendations Assessment, Development, and Evaluation was used to assess certainty of evidence. Of 1088 studies screened, only 2 RCTs were identified. They included 168 infants from 5 countries and were conducted between 1976 and 2015. Neither study compared current World Health Organization-recommended regimens. One multisite trial from 4 countries compared intrathecal gentamicin plus systemic ampicillin/gentamicin to systemic ampicillin/gentamicin and found no difference in mortality (relative risk, 0.88; 95% confidence interval, 0.41-1.53; 1 trial, n = 98, very low certainty of evidence) or adverse events (no events in either trial arm). Another trial in India compared a 10-day versus 14-day course of antibiotics and found no difference in mortality (relative risk, 0.88; 95% confidence interval, 0.41-1.53; 1 trial, n = 98, very low certainty of evidence) or other outcomes. Trial data on the efficacy of antibiotic regimens in young infant meningitis are scarce. Rigorous RCTs are needed to inform recommendations for optimal antibiotic regimens for meningitis treatment in this vulnerable population, particularly within the context of changing epidemiology and increasing antimicrobial resistance.

Adjunctive Single-Dose Liposomal Amphotericin to Prevent Cryptococcal Meningitis in People With Human Immunodeficiency Virus (HIV)-Associated Cryptococcal Antigenemia and Low Plasma Cryptococcal Antigen (CrAg) Titers.

Cryptococcal meningitis is a leading cause of AIDS-related mortality. Cryptococcal antigen (CrAg) predicts the development of meningitis. Historically, despite standard- of-care fluconazole, 25%-30% of asymptomatic CrAg-positive persons develop breakthrough meningitis or death. We evaluated whether adding single high-dose liposomal amphotericin B to standard pre-emptive fluconazole therapy could improve meningitis-free survival. Participants with human immunodeficiency virus (HIV) and asymptomatic cryptococcal antigenemia in Uganda were randomized to liposomal amphotericin B (10 mg/kg once) with fluconazole or fluconazole alone through 24 weeks. We compared 24-week, meningitis-free survival time between treatment groups. After the second interim review, the Data Safety and Monitoring Board recommended no further enrollment of participants with low plasma CrAg lateral flow assay titers (≤1:80) due to futility. Herein, we present the results of participants with low plasma CrAg titers. 168 participants enrolled into the ACACIA trial had low plasma CrAg titers (≤1:80). During 24 weeks of follow-up, meningitis or death occurred in 14.5% (12/83) of participants randomized to liposomal amphotericin B with fluconazole versus 10.6% (9/85) assigned to fluconazole alone (hazard ratio, 1.42; 95% CI, .60-3.36; P = .431). Adverse events were more frequent in participants assigned to the intervention versus standard-of-care (28% vs 12%; P = .011). Among CrAg-positive persons with low titers (≤1:80), the addition of single-dose liposomal amphotericin B to fluconazole as pre-emptive therapy provided no additional clinical benefit. This trial provides supportive evidence that, in asymptomatic populations with low plasma CrAg titers, lumbar punctures are likely unnecessary as administration of meningitis treatment did not improve outcomes. Clinicaltrials.gov (NCT03945448).

Exploring the destructive synergy between IL-33 and Suilysin hemolysis on blood-brain barrier stability.

Streptococcus suis type 2 (SS2) is a zoonotic pathogen capable of eliciting meningitis, presenting significant challenges to both the swine industry and public health. Suilysin (Sly), one of SS2 most potent virulence determinants, releases a surfeit of inflammatory agents following red blood cell lysis. Notably, while current research on Sly role in SS2-induced meningitis predominantly centers on its interaction with the blood-brain barrier (BBB), the repercussions of Sly hemolytic products on BBB function have largely been sidestepped. In this vein, our study delves into the ramifications of Sly-induced hemolysis on BBB integrity. We discern that Sly hemolytic derivatives exacerbate the permeability of Sly-induced in vitro BBB models. Within these Sly hemolytic products, Interleukin-33 (IL-33) disrupts the expression and distribution of Claudin-5 in brain microvascular endothelial cells, facilitating the release of Interleukin-6 (IL-6) and Interleukin-8 (IL-8), thereby amplifying BBB permeability. Preliminary mechanistic insights suggest that IL-33-driven expression of IL-6 and IL-8 is orchestrated by the p38-mitogen-activated protein kinase signaling, whereas matrix metalloproteinase 9 mediates IL-33-induced suppression of Claudin-5. To validate these in vitro findings, an SS2-infected mouse model was established, and upon intravenous administration of growth stimulation expressed gene 2 (ST2) antibodies, in vivo results further underscored the pivotal role of the IL-33/ST2 axis during SS2 cerebral invasion. In summation, this study pioneerly illuminates the involvement of Sly hemolytic products in SS2-mediated BBB compromise and spotlights the instrumental role and primary mechanism of IL-33 therein. These insights enrich our comprehension of SS2 meningitis pathogenesis, laying pivotal groundwork for therapeutic advancements against SS2-induced meningitis.IMPORTANCEThe treatment of meningitis caused by Streptococcus suis type 2 (SS2) has always been a clinical challenge. Elucidating the molecular mechanisms by which SS2 breaches the blood-brain barrier (BBB) is crucial for the development of meningitis therapeutics. Suilysin (Sly) is one of the most important virulence factors of SS2, which can quickly lyse red blood cells and release large amounts of damage-associated molecular patterns, such as hemoglobin, IL-33, cyclophilin A, and so on. However, the impact of these hemolytic products on the function of BBB is unknown and ignored. This study is the first to investigate the effect of Sly hemolytic products on BBB function. The data are crucial for the study of the pathogenesis of SS2 meningitis and can provide an important reference for the development of meningitis therapeutics.

Role of Serum Procalcitonin in Monitoring the Response to Treatment of Pediatric Bacterial Meningitis

Abstract Background Early diagnosis and initial therapy are important to reduce the complications of acute bacterial meningitis (ABM). The gold standard in diagnosing bacterial meningitis is by demonstrating the presence of bacteria in cerebrospinal fluid (CSF) samples via CSF cultures. However, CSF culture requires at least a day or more, and has limited sensitivity. Serum procalcitonin (PCT) is one of the most sensitive biomarkers for identification of bacterial from non-bacterial meningitis. This study was done to evaluate serum PCT as a marker to help in ABM diagnosis specially after oral antibiotics intake or when cerebrospinal fluid (CSF) culture is negative and to assess its correlation with outcome of ABM in children. Methods This is a prospective cohort study that included children who presented to Ain Shams University Children hospital over a period of 6 months. Participants were confirmed cases of ABM (laboratory- confirmed by culture) or suspected to have ABM (presented with sudden onset high fever and signs of meningeal irritation with CSF examination showing at least one of the following: 1. turbid appearance; 2. leukocytosis (&amp;gt; 100cells/mm3); 3. leukocytosis (10-100 cells/mm3) and either an a) elevated protein (&amp;gt; 100 mg/dl) or b) decreased glucose (&amp;lt; 40mg/dl)). The PCT levels were measured on admission and 72hours after treatment. Results A total of 38 ABM cases participated in this study. All the 38 cases showed elevated levels of PCT on admission. There was a significant drop in the mean of PCT level after 72h of treatment compared to level on admission (7.1±6.5 vs. 11.4±3.7, p = 0.001) respectively. There was a significant difference in the mean of PCT level between cases with good outcome (full recovery) versus poor outcome (death or neurological sequalae), on admission (7.2±2.8 vs. 13.2±4.4, p &amp;lt; 0.001) and 72h after treatment (4.2±3.5 vs. 12.9±5.3, p &amp;lt; 0.001) respectively. Conclusion Serum PCT levels were high in all patients with ABM, including those who received oral antimicrobials for 1-3 days before admission. The decline in PCT levels after treatment was associated with good outcome in our cohort.

Physiologically based pharmacokinetic modelling of cefoperazone in paediatrics.

Cefoperazone is commonly used off-label in the treatment of bacterial meningitis and sepsis in children, and the pharmacokinetic (PK) data are limited in this vulnerable population. The goal of this study was to develop a physiologically based pharmacokinetic (PBPK) model to predict pediatric cefoperazone exposure for rational dosing recommendations. A cefoperazone PBPK model for adults was first constructed using Simcyp V22 simulator. Subsequently, the model was extended to children based on the built in age-dependent physiological parameters, while the drug characteristics remained unchanged. The verified pediatric PBPK model was then utilized to assess the rationality of the common dosing regimens for children at different age groups. Cefoperazone PBPK model included elimination via biliary excretion, glomerular filtration, and organic anion transporter 3 (OAT3)-mediated tubular secretion. 95.2% of the observed mean concentrations and 100% of the area under the plasma drug concentration-time curve (AUC) and peak concentration (Cmax) in adults were within a twofold range of model mean predictions. Good predictive accuracy was also observed in children, including neonates. 50 mg/kg q12h cefoperazone demonstrated effective target attainment in virtual term neonates (<1 month) when the MIC was ≤1 mg/L, adhering to the stringent PK/PD target of 75% fT > MIC. 37.5 mg/kg q12h cefoperazone achieved the common 50% fT > MIC target for an MIC ≤ 0. 25 mg/L in virtual pediatric patients ranging from 1 month to 18 years of age. A pediatric PBPK model was developed for cefoperazone, and it could serve as the basis for deriving rational dosing regimens in children.

Efficacy of linezolid in the treatment of tuberculous meningitis: a meta-analysis.

Tuberculous meningitis (TBM) is a severe extra-pulmonary tuberculosis with high fatality. This meta-analysis aimed to assess the impact of linezolid on TBM treatment outcomes. We searched multiple databases for studies published up to May 18, 2024 comparing the effects of linezolid on TBM. Meta-analysis was conducted using Review Manager 5.4. Our findings indicated that linezolid may reduce treatment failure risk (RR = 0.42 (0.20, 0.89), p = 0.02) and improve temperature recovery (RR = 1.56 (1.21, 2.02), p < 0.001) in TBM patients. The analysis suggests a positive association between linezolid treatment and therapeutic improvements, with no significant adverse reactions reported.

Comparison of Early Fungicidal Activity and Mortality Between Daily Liposomal Amphotericin B and Daily Amphotericin B Deoxycholate for Cryptococcal Meningitis

Abstract Background Limited data exist on the antifungal activity of daily liposomal amphotericin B with flucytosine induction regimens for cryptococcal meningitis, which are recommended in high-income countries. Liposomal amphotericin B monotherapy at 3 mg/kg previously failed to meet noninferiority criteria compared to amphotericin B deoxycholate in its registrational clinical trial. We aimed to compare the quantitative antifungal activity and mortality between daily amphotericin B deoxycholate and daily liposomal amphotericin B among persons with human immunodeficiency virus (HIV)–related cryptococcal meningitis receiving adjunctive flucytosine 100 mg/kg/day. Methods We analyzed data from 3 clinical studies involving participants with HIV-associated cryptococcal meningitis receiving either daily liposomal amphotericin B at 3 mg/kg/day with flucytosine (n = 94) or amphotericin B deoxycholate at 0.7–1.0 mg/kg/day with flucytosine (n = 404) as induction therapy. We compared participant baseline characteristics, cerebrospinal fluid (CSF) early fungicidal activity (EFA), and 10-week mortality. Results We included 498 participants in this analysis, of whom 201 had available EFA data (n = 46 liposomal amphotericin B; n = 155 amphotericin B deoxycholate). Overall, there is no statistical evidence that the antifungal activity of liposomal amphotericin B (mean EFA, 0.495 [95% confidence interval {CI}, .355–.634] log10 colony-forming units [CFU]/mL/day) differ from amphotericin B deoxycholate (mean EFA, 0.402 [95% CI, .360–.445] log10 CFU/mL) (P = .13). Mortality at 10 weeks trended lower for liposomal amphotericin B (28.2%) versus amphotericin B deoxycholate (34.6%) but was not statistically different when adjusting for baseline characteristics (adjusted hazard ratio, 0.74 [95% CI, .44–1.25]; P = .26). Conclusions Daily liposomal amphotericin B induction demonstrated a similar rate of CSF fungal clearance and 10-week mortality as amphotericin B deoxycholate when combined with flucytosine for the treatment of HIV-associated cryptococcal meningitis.