Tuberculous meningitis

Matrix metalloproteinase-9 (MMP-9): A macromolecular mediator in CNS infections: A review

Matrix metalloproteinase-9 (MMP-9) is a macromolecular zinc-dependent endopeptidase that plays a critical role in the pathogenesis of Central Nervous System (CNS) infections by modulating extracellular matrix remodelling and blood-brain barrier (BBB) dynamics. This review elucidates the structural and functional properties of MMP-9, highlighting its distinct domain architecture that enables substrate specificity and regulatory mechanisms. MMP-9-mediated BBB disruption is a hallmark of bacterial, viral, fungal, and parasitic CNS infections, facilitating immune cell infiltration and pathogen entry while exacerbating neuroinflammation and tissue damage. Elevated MMP-9 levels in cerebrospinal fluid (CSF) correlate with disease severity, suggesting its potential as a diagnostic biomarker. Advances in therapeutic strategies targeting MMP-9, including small molecule inhibitors, monoclonal antibodies, and peptide-based therapies, demonstrate promising results in mitigating BBB disruption and neuroinflammation. This comprehensive review underscores the dual role of MMP-9 as both a biomarker and therapeutic target, advocating for its inclusion in adjunctive treatment regimens to improve outcomes in CNS infections. Future research should focus on refining MMP-9 inhibitors for clinical use, ensuring specificity, and minimizing off-target effects to harness its full therapeutic potential.

Chasing the "White Plague" in the Barbaricum of the Carpathian Basin - A case with tuberculous meningitis discovered in a Sarmatian-period (2nd-3rd-century-CE) storage pit from the archaeological site of Kiskundorozsma-Daruhalom-dűlő II (Hungary)

The aim of our paper is to demonstrate a case (KD429) with tuberculous meningitis (TBM) from the 2nd-3rd‒century‒CE Carpathian Basin. The skeleton of KD429 was subject to a detailed macromorphological evaluation, focusing on the detection of pathological lesions likely related to tuberculosis (TB). It was the presence of endocranial alterations, especially the TB-specific granular impressions, based on which the diagnosis of TBM was established in KD429. Besides KD429, only eight cases with TB have been published from the Sarmatian-period (1st-5th centuries CE) Carpathian Basin. Reports of archaeological cases with TB, like KD429, can provide invaluable information about the spatio-temporal distribution of the disease in the past. Nonetheless, to get a more accurate picture about the burden that TB may have put on the Sarmatians, the systematic macromorphological (re-)evaluation of their osteoarchaeological series would be advantageous. Interestingly, the skeleton of KD429 was unearthed from not a grave-pit but a storage pit from the archaeological site of Kiskundorozsma-Daruhalom-dűlő II (Hungary). At the current state of research, the motive behind the exclusion of KD429 from the "normal" burial custom cannot be determined; therefore, it remains an open question whether their disease (TBM) played a role in it or not.

Lactate-Dehydrogenase-5 May Play a Key Role in the Disturbance of Brain Energy Caused by Tuberculous Meningitis

BACKGROUND

The conversion of pyruvate to lactate is primarily catalyzed by lactate-dehydrogenase-5 (LDH-5), which comprises four lactate-dehydrogenase-A (LDHA) subunits. However, the mechanism of LDH-5 in tuberculous meningitis (TBM) remains elusive.

METHODS

Thirty-two samples of cerebrospinal fluid (CSF) were collected, including 15 from individuals without central nervous system (CNS) infectious diseases (control group) and 17 from individuals with TBM (TBM group). Based on the results of brain imaging, nine patients with TBM with meningeal enhancement were included in the meninges group. Eight patients with TBM with lesions in the brain parenchyma were included in the brain parenchyma group. The levels of adenosine triphosphatase (ATP), lactate, LDH-1, pyruvate and LDH-5 in the CSF were assessed. Subsequently, the levels of ATP, pyruvate and lactate, as well as the amplitude and frequency of action potentials (APs) in neurons overexpressing LDHA, were investigated.

RESULTS

Reduced levels of pyruvate and ATP and elevated levels of lactate and LDH-5 were observed in the CSF of individuals with TBM. The ATP level was decreased in the brain parenchyma group. In neurons with LDHA overexpression, the lactate level increased, while ATP and pyruvate levels, as well as the amplitude and frequency of APs, decreased.

CONCLUSION

Elevated levels of LDH-5 in the CNS of individuals with TBM may lead to a disturbance in brain energy and negatively affect neuronal activity.

Value of contrast-enhanced ultrasound assisted core needle biopsy in the diagnosis of cervical lymph node tuberculosis

Aim

To investigate the value of contrast-enhanced ultrasound (CEUS) assisted core needle biopsy (CNB) in the diagnosis of cervical lymph node tuberculosis (LN TB) and improve the positive rate of cervical LN TB.

Methods

We retrospectively analyzed 730 samples obtained from July 2010 to January 2025 from patients treated with effective antituberculosis therapy and with microbiologically confirmed and surgical pathologically proven cervical lymph node enlargement who had undergone CEUS- CNB at our hospital. All patients were divided into two groups according to the historical control method. The CEUS group (2017-2025) underwent CEUS- CNB (485 cases), whereas the US group (2010-2018) underwent US-guided CNB (245 cases). The positive rates of pathological diagnosis and Xpert Mycobacterium tuberculosis complex (MTBC) and resistance to rifampin (RIF) (MTB/RIF) assay diagnoses were compared between the groups.

Results

The specimens' integrity was significantly higher after CNB in the CEUS group than in the US group (CEUS group: 72.30%; US group: 45.49%), and visual satisfaction of sampling in the CEUS group was higher (χ2: 47.651, P < 0.001). Histopathological examination sensitivity, specificity, positive predictive value, and negative predictive value were higher in the CEUS group than in the US group. The sensitivity of the Xpert MTB/RIF assay was significantly higher in the CEUS group than in the US group.

Conclusion

The study results support the clinical use of CEUS for improving the diagnostic performance and positive rate for cervical LN TB.

Are endocranial granular impressions pathognomonic of tuberculous meningitis or a marker of tuberculous infection? An investigation on a medieval osteoarcheological assemblage from Italy

OBJECTIVES

In recent paleopathological literature, granular impressions on the endocranial surface are considered pathognomonic of tuberculous meningitis. This study aims to verify the presence of granular impressions and assess their relationship with tuberculosis in an archeological human skeletal assemblage.

MATERIALS

The study analyzed the endocranial surfaces of 212 skulls (38 non-adults and 174 adults) from the medieval site of Pieve di Pava, Italy.

METHODS

Macroscopic and stereomicroscopic examination of the endocranial surface was conducted to evaluate the presence, location, and manifestation of granular impressions.

RESULTS

Granular impressions affected more than half of the individuals, with no statistical difference between males and females.

CONCLUSIONS

The high frequency of granular impressions challenges their interpretation as pathognomonic of tuberculous meningitis, a rare complication of tuberculosis affecting the central nervous system. Instead, these lesions should be considered indicative of bacteremia, when bacilli reach the central nervous system and form tubercles on the meninges. It cannot be established whether these tubercles were quiescent or had ruptured, leading to tuberculous meningitis.

SIGNIFICANCE

Based on the pathogenic life cycle of M. tuberculosis, as defined in clinical settings, it seems prudent to consider granular impressions as a marker of tuberculosis infection, rather than of active tuberculosis disease or tuberculous meningitis in paleopathology.

LIMITATIONS

Research limitations include the smaller number of non-adults compared to adults.

SUGGESTIONS FOR FURTHER RESEARCH

Screening of granular impressions in other large osteoarcheological assemblages could provide new and more reliable data on the spread of tuberculosis infection across different social contexts, geographical settings, and historical periods.

Pharmacokinetic and Pharmacodynamics of Clofazimine Nano-in-Microparticles: Enhanced Brain Delivery and CNS Tuberculosis Amelioration via Intranasal Administration

Mycobacterium tuberculosis (Mtb) demonstrates a proclivity for infecting extrapulmonary sites, notably the brain. Treating these extrapulmonary tuberculosis (TB) manifestations is challenging due to the difficulty of drug delivery across the blood-brain barrier. Clofazimine (CLF) has exhibited promising activity against Mtb, including multidrug-resistant variants, in vitro and in preclinical animal models. However, its clinical implication is restricted owing to poor physicochemical and pharmacokinetic properties. This study aims to develop CLF nano-in-microparticles (CLF-NIMs) for brain drug delivery for central nervous system TB (CNS-TB) treatment via the intranasal route. Simultaneously, the potential dissemination of TB bacilli to the brain was investigated. Following treatment, colony-forming unit (CFU) enumeration was conducted in both the brain and lung tissues to assess mycobacterial burden. Concurrently, drug concentrations were quantified in serum, brain, and lung tissue, enabling a comprehensive evaluation of pharmacokinetics and tissue-specific drug distribution. In pharmacokinetic investigations of CLF-NIMs, significant accumulation of CLF was observed in brain tissue compared to orally administered CLF, surpassing the minimum inhibitory concentration of CLF. In a murine CNS-TB model, intranasal insufflation of CLF-NIMs for 4 weeks led to a substantial reduction (∼0.99 ± 0.57 Log10CFU/gram) in CFU count in the brain compared to oral administration of CLF (2.45 ± 0.47 Log10CFU/gram). These promising preclinical results indicate that CLF-NIMs are well-tolerated and exhibit significant anti-TB activity in a murine CNS-TB model.

Pharmacometabolomics in TB meningitis-Understanding the pharmacokinetic, metabolic, and immune factors associated with anti-TB drug concentrations in cerebrospinal fluid

Poor penetration of many anti-tuberculosis (TB) antibiotics into the central nervous system (CNS) is thought to be a major driver of morbidity and mortality in TB meningitis (TBM). While the amount of a particular drug that crosses into the cerebrospinal fluid (CSF) varies from person to person, little is known about the host factors associated with interindividual differences in CSF concentrations of anti-TB drugs. In patients diagnosed with TBM from the country of Georgia (n = 17), we investigate the association between CSF concentrations of anti-TB antibiotics and multiple host factors including serum drug concentrations and CSF concentrations of metabolites and cytokines. We found > 2-fold differences in CSF concentrations of anti-TB antibiotics from person to person for all drugs tested including cycloserine, ethambutol, imipenem, isoniazid, levofloxacin, linezolid, moxifloxacin, pyrazinamide, and rifampin. While serum drug concentrations explained over 30% of the variation in CSF drug concentrations for cycloserine, isoniazid, linezolid, and pyrazinamide (adjusted R2 ≥ 0.3, p < 0.001 for all), there was no significant association between serum concentrations of imipenem and ethambutol and their respective CSF concentrations. CSF concentrations of carnitines were significantly associated with concentrations of ethambutol and imipenem (q < 0.05), and imipenem was the only antibiotic significantly associated with CSF cytokine concentrations. These results indicate that there is high interindividual variability in CSF drug concentrations in patients treated for TBM, which is only partially explained by differences in serum drug concentrations. With the exception of imipenem, there was no association between CSF drug concentrations and concentrations of cytokines and chemokines.

Distinct features of ANCA-associated hypertrophic pachymeningitis compared with other etiologies: findings from a study of 74 patients

OBJECTIVES

We aimed to characterize the clinical and radiological features, and outcomes, of a large cohort of hypertrophic pachymeningitis (HP) patients from a single centre.

METHODS

We conducted a retrospective study at a tertiary referral centre, encompassing patients diagnosed with HP between 2003 and 2022. The diagnosis of HP relied on the identification of thickening of the dura mater via MRI of the brain or spine.

RESULTS

We included 74 patients, with a mean age of 43.6 ± 14.2 years, of whom 37 (50%) were male. Among the 74, 32 (43.2%) had an immune-mediated origin, including 21 with granulomatosis with polyangiitis (GPA) (predominantly PR3-ANCA positive), four with SLE, three with IgG4-related disease, three with idiopathic HP, and one with RA. Non-immune-mediated HP accounted for 45 cases (56.8%). Within this category, 21 (28.4%) were infectious cases, with 14 having Mycobacterium tuberculosis infection (TB-HP), and 21 (28.4%) having malignancy-associated HP. The clinical and MRI characteristics exhibited variations among the four etiological groups. Hypoglycorrhachia was primarily observed in infectious HP and malignancy-associated HP. Immune-mediated HP was associated with a peripheral pattern of contrast enhancement and the Eiffel-by-night sign. MRI features strongly indicative of TB-HP included leptomeningeal involvement, brain parenchymal lesions, and arterial stroke. MPO-ANCA GPA was associated with a higher prevalence of spinal HP.

CONCLUSIOS

Within our cohort, GPA and Mycobacterium tuberculosis emerged as the predominant causes of HP. We identified significant disparities in clinical and radiological features among the various etiologies, which could have implications for diagnosis.

Tuberculosis: An Update for the Clinician

Tuberculosis (TB) remains a significant global health threat with high mortality and efforts to meet WHO End TB Strategy milestones are off-track. It has become clear that TB is not a dichotomous infection with latent and active forms but presents along a disease spectrum. Subclinical TB plays a larger role in transmission than previously thought. Aerosol studies have shown that undiagnosed TB patients, even with paucibacillary disease, can be highly infectious and significantly contribute to TB spread. Encouraging clinical results have been seen with the M72/AS01E vaccine. If preliminary results can be confirmed in ongoing larger trials, modelling shows the vaccine can positively impact the epidemic. TB preventive therapy (TPT), especially for high-risk groups like people living with HIV and household contacts of drug-resistant TB patients, has shown efficacy but implementation is resource intensive. Treatment options for infectious patients have grown rapidly. New shorter, all-oral treatment regimens represent a breakthrough, but progress is threatened by rising resistance to bedaquiline. Many new chemical entities are entering clinical trials and raise hopes for all-new regimens that could overcome rising resistance rates to conventional agents. More research is needed on the management of complex cases, such as central nervous system TB and severe HIV-associated TB. Post-TB lung disease (PTLD) is an under-recognised but growing concern, affecting millions of survivors with lasting respiratory impairment and increased mortality. Continued investment in development of TB vaccines and therapeutics, treatment shortening, and management of TB sequelae is critical to combat this ongoing public health challenge.

Combined cerebrospinal fluid sCD163, MMP-9, with serum NCAM1 protein levels for predicting the prognosis of patients with tuberculous meningitis

Tuberculous meningitis (TBM) is the most serious type of tuberculosis infection, and there is a lack of accurate diagnostic targets for TBM. Therefore, it is of great clinical and public health significance to find a specific target for early diagnosis and prediction of the prognosis of TBM. From January 2021 to February 2024, 110 TBM patients and 122 patients with non-tumor, non-infectious headaches were admitted to Hunan Chest Hospital. To compare the two groups, cerebrospinal fluid (CSF) levels of sCD163 and MMP-9, as well as serum NCAM1 protein levels, were detected by ELISA. Multivariate logistic regression analysis or Spearman analysis was then performed to investigate the correlation between these protein levels and the MRC (Medical Research Council) stage or the short-term prognosis in TBM patients. sCD163 and MMP-9 were elevated in the CSF of TBM patients compared to controls. Oppositely, the protein levels of serum NCAM1 was decreased. The levels of CSF sCD163, MMP-9 and serum NCAM1 are associated with MRC stage and short-term prognosis of TBM patients, and the combined CSF sCD163, MMP-9 and serum NCAM1 have the best value in predicting the short-term prognosis of TBM patients.

Trans-nasal brain delivery of anti-TB drugs by methyl-β-cyclodextrin microparticles show efficient mycobacterial clearance from central nervous system

Central nervous system tuberculosis (CNS-TB) is the most severe extra-pulmonary manifestation of tuberculosis (TB), facing significant challenges due to the limited penetration of anti-TB drugs (ATDs) across the blood-brain barrier (BBB) and their insufficient concentrations at the site of infection. This study aimed to enhance the efficacy of ATDs by encapsulating them in methyl-β-cyclodextrin (M-β-CD) microparticles (ATD-MP) using spray drying, intended for intranasal delivery to manage CNS-TB. M-β-CD microparticles loaded with isoniazid (INH) and rifampicin (RIF) exhibited spherical shapes with slightly deflated surfaces and particle sizes of 6.24 ± 0.77 μm and 5.97 ± 0.50 μm, respectively. M-β-CD improved the permeation of ATDs through RPMI-2650 cell monolayers while reducing drug cytotoxicity. Pharmacokinetic and biodistribution analysis demonstrated that intranasal administration of ATD-MP significantly enhanced the trans-nasal brain delivery of ATDs and their distribution in the brain, achieving the minimum inhibitory concentration. In a murine model of CNS-TB, intranasal insufflation of ATD-MP for four weeks led to a significant reduction (∼0.78 Log10 CFU) in mycobacterial burden in the brain compared to the untreated group (∼3.60 Log10 CFU). These preclinical results underscore the potential of intranasal administration of M-β-CD microparticles as an effective therapeutic strategy for combating brain inflammation in CNS-TB.

Efficacy of nintedanib as a host-directed therapy candidate in the treatment of tuberculosis

BACKGROUND

The lengthy duration and high frequency of drug resistance associated with currently used antimycobacterial drug treatments have intensified the need for alternative therapies against Mycobacterium tuberculosis, the causative agent of TB.

METHODS

MICs and intracellular macrophage cfu counts were tested to evaluate the antibacterial activity of nintedanib and pirfenidone against drug-susceptible and -resistant M. tuberculosis. A chronic murine model of pulmonary infection was used to assay the therapeutic efficacy of nintedanib. Macrophage transcriptome deep sequencing, a confocal assay, siRNA knockdown, Western blotting, quantitative RT-PCR and a cfu assay were used to investigate the antibacterial mechanism of nintedanib.

RESULTS

The MIC90 of nintedanib against M. tuberculosis standard strain H37Rv was 23.56-40.51 mg/L. TB murine model studies showed that nintedanib, coadministered with isoniazid, rifampicin and pyrazinamide, shortened treatment duration, and ameliorated pulmonary inflammation and fibrosis. In mechanism studies, transcriptome sequencing analysis revealed that nintedanib may eliminate M. tuberculosis through up-regulating macrophage autophagy. Furthermore, inhibition of autophagy by using siRNA targeting ATG5 or the autophagy inhibitor 3-methyladenine almost completely abolished nintedanib-mediated suppression of M. tuberculosis. Nintedanib induced autophagy by the JAK2/STAT3/Beclin1 pathway. When JAK2 or Beclin1 were knocked down through siRNA, nintedanib no longer inhibited M. tuberculosis. JAK2 activator coumermycin A1 and STAT3 agonist colivelin also reversed this phenotype.

CONCLUSIONS

In vitro activity of nintedanib against drug-susceptible and -resistant M. tuberculosis and efficacy in murine infections warrant the continued clinical evaluation of nintedanib as a new adjuvant therapy for standard treatment of TB.

Comparison of mNGS with conventional methods for diagnosis of cryptococcal meningitis: a retrospective study

The application of metagenomic next-generation sequencing (mNGS) in the diagnosis of cryptococcal meningitis is relatively under characterized. Here, we retrospectively evaluated data from cryptococcal meningitis patients who were tested using mNGS and/or routine testing, including fungal culture, India ink staining, and cryptococcal antigen (CrAg) testing. The performance of mNGS was then assessed. Initial cerebrospinal fluid (CSF) samples were collected from 65 patients with suspected central nervous system (CNS) infection and tested using conventional tests and/or mNGS. mNGS offers a culture-independent approach, facilitating a rapid and unbiased detection of a broad spectrum of pathogens. Patients with bacterial tuberculous or viral meningitis were used as mNGS-positive controls and one autoimmune encephalitis patient was used as an mNGS-negative control. In the 45 patients diagnosed with cryptococcal meningitis, the sensitivity, specificity, positive predictive value, negative predictive value, and concordance rate of mNGS were 92%, 100%, 100%, 90.9%, and 95.6%, respectively. Compared to conventional methods, the sensitivity of mNGS was slightly lower than CrAg tests (96.7%) but higher than India ink (79.5%) and culturing (63.4%). Of the two negative mNGS cases (2/25, 8.0%), one was positive by India ink staining, culture, and CrAg testing, while the other was positive only by CrAg testing. A combination of mNGS and conventional methods enhanced the detection rate to 100%. Our study demonstrates that both CrAg and mNGS offer excellent diagnostic accuracy for cryptococcal meningitis, and utilizing both tests can enhance clinical assessment and patient management.

Prolonged Corticosteroid Use in the Treatment of Tuberculous Meningoencephalitis: A Case Report

Tuberculous meningoencephalitis is a rare manifestation of Mycobacterium tuberculosis (Mtb), with the most severe form and highest mortality. It can cause multiple complications, and treatment is difficult, as drugs cannot properly diffuse through the haemato-encephalitic barrier. We reported the case of a 17-year-old female patient who was admitted to the emergency room department with a fever for previous two weeks (up to 39 °C), dizziness, difficulty walking, and weight loss. Magnetic resonance imaging indicated possible meningoencephalitis, and a CT scan of the lungs visualised miliary infiltrates in both lungs. After repeated tests, Mtb DNA was found in the bronchial wash, cerebrospinal fluid, faeces, and urine via an Xpert/Rif Ultra test. Treatment was started with isoniazid, rifampicin, ethambutol, pyrazinamide, and corticosteroids as well. Although treatment was initiated within the first few days in the hospital, a reduction in glucocorticoid dosage worsened the patient's neurological state, making treatment even more challenging. Prolonged use of glucocorticoids led to an improvement in the stage of the condition. Further, over time, the patient's condition improved. Pulmonary infiltrations were not found after 2.5 months of starting therapy. Conclusions: Timely treatment is crucial for improving the prognosis of patients with miliary tuberculosis and tuberculous meningoencephalitis. Prompt recognition of symptoms and accurate diagnosis are essential to initiate effective treatment strategies. In this patient's case, prolonged use of corticosteroids reduced neurologic complications, and ongoing treatment gradually improved the patient's condition.

Stroke thrombolysis in tuberculous meningitis

A woman in her 30s presented with sudden onset right-sided weakness, speech difficulties and transient loss of consciousness. She had a medical history of migraine, hypothyroidism and cervical lymphadenopathy. On examination, her National Institutes of Health Stroke Scale (NIHSS) score was 8 due to dense right-sided hemiparesis. CT brain imaging showed no intracranial haemorrhage but revealed incidental findings of left supraclavicular and cervical lymphadenopathy. CT intracranial angiogram did not show large vessel occlusion. She received thrombolytic treatment for ischaemic stroke. NIHSS improved to 3 with no immediate complications. Following admission, she developed swinging fever, seizures and fluctuating right-sided weakness. Repeat MRI of the head showed leptomeningeal enhancement. Biopsy of the cervical lymph nodes showed histiocytic granulomatous lymphadenitis, which was suggestive of tuberculous meningitis (TBM). She was treated with quadruple antimicrobial therapy and steroids for TBM, as well as aspirin for ischaemic stroke, which resulted in good clinical improvement.

Tuberculous meningitis diagnosis and treatment: classic approaches and high-throughput pathways

Tuberculous meningitis (TBM), a severe form of non-purulent meningitis caused by Mycobacterium tuberculosis (Mtb), is the most critical extrapulmonary tuberculosis (TB) manifestation, with a 30-40% mortality rate despite available treatment. The absence of distinctive clinical symptoms and effective diagnostic tools complicates early detection. Recent advancements in nucleic acid detection, genomics, metabolomics, and proteomics have led to novel diagnostic approaches, improving sensitivity and specificity. This review focuses on nucleic acid-based methods, including Xpert Ultra, metagenomic next-generation sequencing (mNGS), and single-cell sequencing of whole brain Tissue, alongside the diagnostic potential of metabolomic and proteomic biomarkers. By evaluating the technical features, diagnostic accuracy, and clinical applicability, this review aims to inform the optimization of TBM diagnostic strategies and explores the integration and clinical translation of multi-omics technologies.

Advancing the chemotherapy of tuberculous meningitis: a consensus view

Tuberculous meningitis causes death or disability in approximately 50% of affected individuals and kills approximately 78 200 adults every year. Antimicrobial treatment is based on regimens used for pulmonary tuberculosis, which overlooks important differences between lung and brain drug distributions. Tuberculous meningitis has a profound inflammatory component, yet only adjunctive corticosteroids have shown clear benefit. There is an active pipeline of new antitubercular drugs, and the advent of biological agents targeted at specific inflammatory pathways promises a new era of improved tuberculous meningitis treatment and outcomes. Yet, to date, tuberculous meningitis trials have been small, underpowered, heterogeneous, poorly generalisable, and have had little effect on policy and practice. Progress is slow, and a new approach is required. In this Personal View, a global consortium of tuberculous meningitis researchers articulate a coordinated, definitive way ahead via globally conducted clinical trials of novel drugs and regimens to advance treatment and improve outcomes for this life-threatening infection.

Tuberculous meningitis in Bhubaneswar, Odisha, during 2016 to 2022

BACKGROUND

The burden of tuberculous meningitis varies substantially by location, and is influenced by the overall burden of tuberculosis in that geographical area, and the age structure of the population. Conventional methods for diagnosis of tuberculous meningitis include acid fast bacilli (AFB) smear and culture. AFB smear has low sensitivity and culture techniques are time consuming. During the last few years, rapid and sensitive molecular methods such as cartridge based nucleic acid amplification technique (CBNAAT) is being used for the diagnosis of tuberculous meningitis. In this study, we evaluated the burden of tuberculosis and rifampicin resistance in suspected cases of tuberculous meningitis in Bhubaneswar, Odisha, during February 2016 to December 2022 using CBNAAT.

METHODS

Under the National Strategic Plan 2012-2017, CBNAAT machines were rolled out in 2016, of which 1 was installed in the National Reference Laboratory (NRL) for Tuberculosis in Bhubaneswar. For this study, retrospective data on CBNAAT testing of cerebrospinal fluid (CSF) samples at the NRL was collected and analyzed from February 2016 to December 2022. All the demographic and laboratory data were entered in Excel 2010 (Microsoft office, USA) for data analysis. The age and sex distribution of the presumptive TB patients, proportion of samples referred from public and private health care facilities, proportion of M. tuberculosis positive CSF samples along with sensitivity to rifampicin was evaluated. The study was approved by the Institutional Human Ethics Committee.

RESULTS

During February 2016 to December 2022, a total of 1627 CSF samples from presumptive TB meningitis patients were received in the NRL for CBNAAT testing. 60.7% (988/1627) of the presumptive TB patients were males. Of the 1627 patients, 3.1% (50/1627) were positive for M. Tuberculosis by CBNAAT. 56% (28/50) of the patients positive for tuberculous meningitis were males. The positivity for M. tuberculosis varied from 2.1% in 2017 to 5.1% in 2021. The CSF positivity for M. tuberculosis ranged from 0.7% in patients aged >60 years to 6.1% in 15-30 years age group. Of the 50 M. tuberculosis positive samples, 6% (3/50) were resistant for rifampicin.

CONCLUSION

Our study which included more than 1600 samples over a period of approximately 7 years found a 3.1% positivity for M. tuberculosis in CSF samples using CBNAAT. 6% of the M. tuberculosis positive samples were resistant to rifampicin. Future studies involving data from other districts of Odisha will help provide a more accurate information on the prevalence of tuberculous meningitis in Odisha state.

Design of RNA Polymerase Inhibitors as Therapeutics for Tuberculous Meningitis

BACKGROUND

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis. 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 tuberculous 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.

METHODS

In this work, ligands having improved BBB permeability and pharmacokinetic and pharmacodynamic properties, either similar to or better than that of rifampicin, have been designed. The BBB permeability of the designed molecules was assessed by using pkCSM, a machine- learning model. Pharmacokinetic properties, drug-likeness, and synthesizability were assessed 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.

RESULTS

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 β of Mycobacterium tuberculosis.

CONCLUSION

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.

Cerebrospinal fluid-induced stable and reproducible SERS sensing for various meningitis discrimination assisted with machine learning

Cerebrospinal fluid (CSF)-based pathogen or biochemical testing is the standard approach for clinical diagnosis of various meningitis. However, misdiagnosis and missed diagnosis always occur due to the shortages of unusual clinical manifestations and time-consuming shortcomings, low sensitivity, and poor specificity. Here, for the first time, we propose a simple and reliable CSF-induced SERS platform assisted with machine learning (ML) for the diagnosis and identification of various meningitis. Stable and reproducible SERS spectra are obtained within 30 s by simply mixing the colloidal silver nanoparticles (Ag NPs) with CSF sample, and the relative standard deviation of signal intensity is achieved as low as 2.1%. In contrast to conventional salt agglomeration agent-induced irreversible aggregation for achieving Raman enhancement, a homogeneous and dispersed colloidal solution is observed within 1 h for the mixture of Ag NPs/CSF (containing 110-140 mM chloride), contributing to excellent SERS stability and reproducibility. In addition, the interaction processes and potential enhancement mechanisms of different Ag colloids-based SERS detection induced by CSF sample or conventional NaCl agglomeration agents are studied in detail through in-situ UV-vis absorption spectra, SERS analysis, SEM and optical imaging. Finally, an ML-assisted meningitis classification model is established based on the spectral feature fusion of characteristic peaks and baseline. By using an optimized KNN algorithm, the classification accuracy of autoimmune encephalitis, novel cryptococcal meningitis, viral meningitis, or tuberculous meningitis could be reached 99%, while an accuracy value of 68.74% is achieved for baseline-corrected spectral data. The CSF-induced SERS detection has the potential to provide a new type of liquid biopsy approach in the fields of diagnosis and early detection of various cerebral ailments.

Risk Prediction Model for Isoniazid Dosing in Tuberculosis Meningitis Patients in Southwest China

Purpose

Tuberculosis meningitis (TBM) has emerged as the most lethal type of disease. The prognosis of meningitis is often related to disease severity and early therapeutic intervention.

Methods

Patients were screened for primary TBM and received a quadruple regimen comprising isoniazid (standard dose of 300 mg/day and high dose of 600 mg/day), rifampin, ethambutol, and pyrazinamide. Further, the indices and prognosis factors of diseased patients were analyzed, using 12-month treatment mortality as the primary observation endpoint. Several predictors included demographic data, clinical presentation, ancillary tests, treatment changes, and isoniazid dose. The data were analyzed using a least absolute shrinkage, the selection operator regression, and multi-factor logistic regression.

Results

Among the selected TBM patients (n=119), 18 patients were dead at the end of December. A total of 68 influencing factors were screened, in which 5 clinical factors were included as potential prognostic factors, including older age, presence of nausea, high MRC grade, imaging suggestive of cerebral infarction, and dose of isoniazid (300 mg/day). The AUC value was recorded as 0.8316832. The validation set confirmed the model's robustness, with an AUC of 0.887 and good calibration performance. These findings highlight the model's potential for clinical application in optimizing isoniazid dosing. The model demonstrated the advantage of predicting the therapeutic outcome of patients.

Conclusion

In summary, the model could be suitable for evaluating the risk of death within 12 months in TBM patients towards assessing the severity and treatment needs of patients. The isoniazid dose is an important factor affecting the prognosis of these patients.

Challenges of Multidrug-Resistant Tuberculosis Meningitis: Current Treatments and the Role of Glutathione as an Adjunct Therapy

Multidrug-resistant tuberculosis (MDR-TB) poses a significant global health threat, especially when it involves the central nervous system (CNS). Tuberculous meningitis (TBM), a severe manifestation of TB, is linked to high mortality rates and long-term neurological complications, further exacerbated by drug resistance and immune evasion mechanisms employed by Mycobacterium tuberculosis (Mtb). Although pulmonary TB remains the primary focus of research, MDR-TBM introduces unique challenges in diagnosis, treatment, and patient outcomes. The effectiveness of current treatments is frequently compromised by poor CNS penetration of anti-TB drugs and the necessity for prolonged therapy, which often involves considerable toxicity. This review explores the potential of cytokine-based adjunct immunotherapies for MDR-TBM, addressing the challenges of balancing pro-inflammatory and anti-inflammatory signals within the CNS. A central focus is the prospective role of glutathione, not only in reducing oxidative stress but also in enhancing host immune defenses against Mtb's immune evasion strategies. Furthermore, the development of vaccines aimed at upregulating glutathione synthesis in macrophages represents a promising strategy to bolster the immune response and improve treatment outcomes. By integrating glutathione and innovative vaccine approaches into MDR-TBM management, this review proposes a comprehensive strategy that targets Mtb directly while supporting immune modulation, with the potential to enhance patient outcomes and reduce treatment related adverse effects. We underscore the urgent need for further research into adjunctive therapies and immunomodulatory strategies to more effectively combat MDR-TBM.

Clinical Significance of Hyponatremia in Tuberculous Meningitis: A Prospective Cohort in Indonesia

Background

Hyponatremia is common in tuberculous meningitis (TBM), but its impact on disease severity and outcomes is unclear.

Methods

In a cohort of 864 adult patients with TBM in Indonesia, we assessed the prevalence and prognostic significance of hyponatremia, classified as moderate (120-130 mEq/L) or severe (<120 mEq/L). Patients received standard antituberculous therapy and corticosteroids and were followed for 1-year mortality.

Results

Hyponatremia occured in 86.8% of patients, with 26% classified as severe. Severe hyponatremia associated with male, younger age, a lower Glasgow Coma Scale (GCS), and markers of more severe disease (P < .05). One-year mortality was 46.5% and associated with older age, HIV infection, lower GCS, markers of neurologic severity, fever, and thrombocytosis. Severe hyponatremia predicted mortality in univariate analysis showed no impact in HIV-positive patients.

Conclusions

Hyponatremia reflects disease severity in TBM but does not independently predict mortality, suggesting limited benefit from agressive correction.

Perplexing paradoxical reactions: navigating the complexity of protracted tuberculosis meningitis-a case report

Tuberculous meningitis (TBM) has considerable mortality and morbidity, and it often presents therapeutic challenges when complicated by paradoxical reactions (PRs). Here, the clinical course of four cases of TBM patients complicated by PRs in a longitudinal TB cohort is described while also providing insights from the larger clinical cohort. Research flow cytometry, biomarker analysis, and drug concentrations were performed on available samples. All participants were initiated on standard antituberculosis therapy (ATT) and enrolled at the onset of PRs (PR group) or 2-4 months after the start of ATT (controls). The four TBM participants highlighted here presented with fevers, headaches, neurological deficits, and fatigue at the initial presentation. Upon diagnosis, all were initiated on rifampin, isoniazid, pyrazinamide, and ethambutol (RHZE) at standard doses and on corticosteroids. The median time to first PR was 37 days with recrudescence of initial TBM signs and symptoms at the time of PR. At the time of referral, all participants had low drug concentrations requiring dose optimization and regimen intensification as well as recrudescent flares upon corticosteroid taper, with one individual developing enlargement of tuberculoma 1 year following completion of ATT. Based on biomarkers and flow cytometry, PRs are characterized by elevated interferon-gamma and ferritin levels in the plasma compared to controls. In the TBM participants, T-cell activation with elevated levels of inflammatory biomarkers in the cerebrospinal fluid (CSF) was seen at the time of PR. These unique and highly detailed TBM cases provide insights into the pathogenesis of PRs, which may assist with future diagnostics and treatment.

Whole blood transcriptional profiles and the pathogenesis of tuberculous meningitis

Mortality and morbidity from tuberculous meningitis (TBM) are common, primarily due to inflammatory response to Mycobacterium tuberculosis infection, yet the underlying mechanisms remain poorly understood. We aimed to uncover genes and pathways associated with TBM pathogenesis and mortality, and determine the best predictors of death, utilizing whole-blood RNA sequencing from 281 Vietnamese adults with TBM, 295 pulmonary tuberculosis (PTB), and 30 healthy controls. Through weighted gene co-expression network analysis, we identified hub genes and pathways linked to TBM severity and mortality, with a consensus analysis revealing distinct patterns between HIV-positive and HIV-negative individuals. We employed multivariate elastic-net Cox regression to select candidate predictors of death, then logistic regression and internal bootstrap validation to choose best predictors. Increased neutrophil activation and decreased T and B cell activation pathways were associated with TBM mortality. Among HIV-positive individuals, mortality associated with increased angiogenesis, while HIV-negative individuals exhibited elevated TNF signaling and impaired extracellular matrix organization. Four hub genes-MCEMP1, NELL2, ZNF354C, and CD4-were strong TBM mortality predictors. These findings indicate that TBM induces a systemic inflammatory response similar to PTB, highlighting critical genes and pathways related to death, offering insights for potential therapeutic targets alongside a novel four-gene biomarker for predicting outcomes.

The value of histopathologic examination and Xpert (MTB/RIF) assay in diagnosis of cervical lymph node tuberculosis after coarse needle biopsy guided by CEUS: a retrospective analysis of 612 cases

OBJECTIVE

To investigate the value of histopathological examination (HPE) and Xpert Mycobacterium tuberculosis bacilli/rifampicin (MTB/RIF) assay in diagnosis of cervical lymph node tuberculosis (LN TB) after coarse needle biopsy (CNB).

METHODS

We retrospectively analyzed 612 samples obtained from October 2017 to August 2023 from patients suspected cervical LN TB with surgically pathological, microbial culture confirmed, and clinically confirmed cervical lymph node enlargement who received ultrasound-guided CNB assisted by contrast-enhanced ultrasound (CEUS) at our hospital. All specimens were assessed by HPE and the Xpert (MTB/RIF) assay. We analyzed the results to determine the diagnostic value of HPE and Xpert (MTB/RIF) assay in samples taken after CEUS-assisted CNB of LN TB, and to evaluate the safety of CNB.

RESULTS

Based on the comprehensive reference standard established in this study, 532 of 612 patients were diagnosed with cervical LN TB, of which 476 were CNB positive cases, the positive rate of diagnosis was 89.5%。The sensitivity, specificity, positive predictive value, negative and predictive value of HPE were 80.4%, 91.2%, 98.4%, 41.2% respectively, while those of the Xpert MTB/RIF assay were 75.7%, 98.7%, 99.7%, 38.0% respectively. No postoperative complications were noted, and the Clavien-Dindo grade was 2.

CONCLUSION

CEUS-assisted CNB has high diagnostic value and is safe for cervical LN TB. The sensitivity of HPE is slightly higher than that of Xpert (MTB/RIF) assay, and the specificity of Xpert (MTB/RIF) assay is higher than that of HPE, so Xpert (MTB/RIF) assay can correct the cervical lymph node tuberculosis with negative HPE.

Effective cerebral tuberculosis treatment via nose-to-brain transport of anti-TB drugs using mucoadhesive nano-aggregates

Central nervous system tuberculosis (CNS-TB) is a severe form of extra-pulmonary tuberculosis with high mortality and morbidity rates. The standard treatment regimen for CNS-TB parallels that of pulmonary TB, despite the challenge posed by the blood-brain barrier (BBB), which limits the efficacy of first-line anti-TB drugs (ATDs). Nose-to-brain (N2B) drug delivery offers a promising solution for achieving high ATD concentrations directly at infection sites in the brain while bypassing the BBB. This study aimed to develop chitosan nanoparticles encapsulating ATDs, specifically isoniazid (INH) and rifampicin (RIF). These nanoparticles were further processed into micro-sized chitosan nano-aggregates (NA) via spray drying. Both INH-NA and RIF-NA showed strong mucoadhesion and significantly higher permeation rates across RPMI 2650 cells compared to free ATDs. Intranasal administration of these NAs to TB-infected mice for four weeks resulted in a significant reduction of mycobacterial load by approximately ∼2.86 Log 10 CFU compared to the untreated group. This preclinical data highlights the efficacy of intranasal chitosan nano-aggregates in treating CNS-TB, demonstrating high therapeutic potential, and addressing brain inflammation challenges. To our knowledge, this study is the first to show nasal delivery of ATD nano-formulations for CNS-TB management.

Development of innovative multi-epitope mRNA vaccine against central nervous system tuberculosis using in silico approaches

Tuberculosis(TB) of the Central nervous system (CNS) is a rare and highly destructive disease. The emergence of drug resistance has increased treatment difficulty, leaving the Bacillus Calmette-Guérin (BCG) vaccine as the only licensed preventative immunization available. This study focused on identifying the epitopes of PknD (Rv0931c) and Rv0986 from Mycobacterium tuberculosis(Mtb) strain H37Rv using an in silico method. The goal was to develop a therapeutic mRNA vaccine for preventing CNS TB. The vaccine was designed to be non-allergenic, non-toxic, and highly antigenic. Codon optimization was performed to ensure effective translation in the human host. Additionally, the secondary and tertiary structures of the vaccine were predicted, and molecular docking with TLR-4 was carried out. A molecular dynamics simulation confirmed the stability of the complex. The results indicate that the vaccine structure shows effectiveness. Overall, the constructed vaccine exhibits ideal physicochemical properties, immune response, and stability, laying a theoretical foundation for future laboratory experiments.

The Impact of GeneXpert Cerebrospinal Fluid Testing on Tuberculous Meningitis Diagnosis in Routine Care in Botswana

Background

Tuberculous meningitis (TBM) disproportionately impacts high-HIV prevalence, resource-limited settings where diagnosis is challenging. The GeneXpert platform has utility in TBM diagnosis, but uptake remains limited. In Botswana, before the introduction of GeneXpert, tuberculosis (TB) testing was only available through mycobacterial culture at the National TB Reference Laboratory. Data describing routine use of Xpert MTB/RIF for cerebrospinal fluid (CSF) testing in resource-limited settings are scarce.

Methods

Electronic records for patients with CSF tested in government facilities in Botswana between 2016 and 2022 were obtained from a central online repository as part of ongoing national meningitis surveillance. Samples were excluded from 1 site where Xpert MTB/RIF is performed universally. The proportion receiving TB-specific investigation on CSF and the number positive for Mycobacterium tuberculosis following increased Xpert MTB/RIF capacity were determined.

Results

The proportion of CSF samples receiving TB-specific investigation increased from 4.5% (58/1288) in 2016 to 29.0% (201/693) in 2022, primarily due to increased analysis with Xpert MTB/RIF from 0.9% (11/1288) to 23.2% (161/693). There was an overall decline in the annual number of CSF samples analyzed, but the proportion with microbiologically confirmed TBM increased from 0.4% to 1.2%. The proportion of samples tested for TB that were collected from health care facilities >100 km from the National TB Reference Laboratory increased with Xpert MTB/RIF rollout from 65.9% (87/132) to 78.0% (494/633).

Conclusions

In Botswana, access to TB culture is challenging in remote populations; more accessible near-patient testing using Xpert MTB/RIF increased the number of patients receiving TB-specific testing on CSF and the number of confirmed TBM cases.

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.

Prevalence, incidence, and case fatality of tuberculous meningitis in adults living with HIV: a systematic review and meta-analysis

BACKGROUND

Tuberculous meningitis (TBM) emerges as a grave complication of tuberculosis in people living with HIV (PLWH). The diagnosis and treatment of TBM pose significant challenges, leading to elevated mortality rates. To comprehensively grasp the epidemiological landscape of TBM in PLWH, a systematic review and meta-analysis were meticulously undertaken.

METHODS

We performed a comprehensive search in PubMed, Embase, and Web of Science from database inception to September 19th, 2023, with no limitations on the publication type. The search terms were HIV/AIDS terms (AIDS OR HIV OR PLWH) and TBM-related terms (tuberculous meningitis OR TBM). Studies included in this meta-analysis evaluated the incidence of TBM among PLWH, or we were able to calculate the incidence of TBM among PLWH from the research.

RESULTS

The analysis revealed that the prevalence of TBM among PLWH was 13.6% (95% CI: 6.6-25.9%), with an incidence rate of 1.5 cases per 1000 persons per year. The case fatality rate was found to be 38.1% (95% CI: 24.3-54.1%). No significant publication bias was observed. Meta-regression analysis identified the proportion of females and finance situation as factors influencing the outcomes.

CONCLUSIONS

Our study highlights TBM as a prevalent opportunistic infection that targets the central nervous system in PLWH. The elevated case fatality rate is especially prominent among PLWH in impoverished regions, underscores the pressing necessity for enhanced management strategies for PLWH suffering from TBM.

TRIAL REGISTRATION

PROSPERO; No: CRD42022338586.

LC-MS metabolomics and lipidomics in cerebrospinal fluid from viral and bacterial CNS infections: a review

There is compelling evidence that a dysregulated immune inflammatory response in neuroinfectious diseases results in modifications in metabolic processes and altered metabolites, directly or indirectly influencing lipid metabolism within the central nervous system (CNS). The challenges in differential diagnosis and the provision of effective treatment in many neuroinfectious diseases are, in part, due to limited understanding of the pathophysiology underlying the disease. Although there are numerous metabolomics studies, there remains a deficit in neurolipidomics research to provide a comprehensive understanding of the connection between altered metabolites and changes in lipid metabolism. The brain is an inherently high-lipid organ; hence, understanding neurolipidomics is the key to future breakthroughs. This review aims to provide an integrative summary of altered cerebrospinal fluid (CSF) metabolites associated with neurolipid metabolism in bacterial and viral CNS infections, with a particular focus on studies that used liquid chromatography-mass spectrometry (LC-MS). Lipid components (phospholipids) and metabolites (carnitine and tryptophan) appear to be the most significant indicators in both bacterial and viral infections. On the basis of our analysis of the literature, we recommend employing neurolipidomics in conjunction with existing neurometabolomics data as a prospective method to enhance our understanding of the cross link between dysregulated metabolites and lipid metabolism in neuroinfectious diseases.

A retrospective study on intracranial mixed infection with tuberculous meningitis in Shenzhen, China

Tuberculous meningitis (TBM) is a prevalent global intracranial infection and the most lethal and disabling form of tuberculosis. TBM with mixed intracranial infections is clinically rare but has a higher mortality rate. To investigate the clinical characteristics of TBM with mixed intracranial infections, demographic and clinical data of TBM and pulmonary tuberculosis (PTB) patients admitted to Shenzhen Third People's Hospital between January 2015 and October 2022 were collected anonymously. A total of 207 cases of TBM were diagnosed, of which 16 cases (7.73%) were TBM with mixed intracranial infections. The overall mortality rate of TBM cases was 16.4%, while the mortality rate of TBM cases with mixed intracranial infections was as high as 35.7%. Compared to simple TBM cases, TBM cases with mixed intracranial infections had severer clinical symptoms. The percentage of human immune deficiency virus (HIV)-positive TBM cases with mixed intracranial infections reached up to 68.8%. HIV co-infection, CD4+/CD8+ T-cell counts less than 1, cranial nerve impairment, paralysis, cerebral infarction, PRO less than 450 mg/L, WBC less than 10 × 106 /L, and CL more than 120 mmol/L were risk factors for TBM cases with mixed intracranial infections. Compared to PTB, HIV co-infection, CD4+ T cell less than 550 /uL, and age less than 45 years were risk factors for TBM, and TBM was associated with higher mortality rates. Our study provides additional data to better understand single TBM and TBM with mixed intracranial infections. More than two-thirds of TBM cases with mixed intracranial infections were HIV-positive. Clinicians should consider the possibility of multiple infections in people with TBM/HIV co-infection.

IMPORTANCE

TBM can cause severe neurological damage and death, and TBM with mixed intracranial infections can exacerbate the damage and poor prognosis of the disease. TBM with mixed intracranial infections is a rare disease, which has led to an incomplete understanding of its clinical features. This study investigated the clinical features of TBM and its associated factors by comparing the characteristics of TBM with mixed intracranial infections, single TBM and pulmonary tuberculosis. This information will help to improve the understanding of TBM, diagnostic accuracy and treatment outcomes.

Efficacy and safety of intrathecal dexamethasone combined with isoniazid in the treatment of tuberculous meningitis: a meta-analysis

BACKGROUND

The treatment regimen for tuberculous meningitis (TBM) remains unclear and requires optimization. There are some reports on successful adjunct intrathecal dexamethasone and isoniazid (IDI) treatment strategies for TBM, however, there is equivocal evidence on their efficacy and safety.

METHODS

A comprehensive search of English and Chinese databases was conducted from inception to February 2024. A meta-analysis was performed on randomized controlled trials (RCTs) estimating the effects of adjunct IDI on conventional anti-TB (C anti-TB) treatments or C anti-TB alone. Efficacy, adverse reaction rate, cerebrospinal fluid (CSF) leukocytes, and CSF protein were used as primary outcome indicators. CSF glucose, CSF chlorides, CSF pressure, recovery time for laboratory indicators and recovery time for clinical symptoms were used as secondary outcome indicators.

RESULTS

A total of 17 studies involving 1360 (IDI group vs. C anti-TB group: 392 vs. 372; higher-dose IDI group vs. lower-dose IDI group: 319 vs. 277) patients were included in our analysis. Efficacy was significantly higher (RR 1.3, 95% CI 1.2-1.4, P < 0.001) and adverse reaction rate was significantly lower in the IDI groups (RR 0.59, 95% CI 0.37-0.92, P = 0.021). Furthermore, CSF leukocytes (WMD - 29.33, 95% CI [- 40.64 to-18.02], P < 0.001) and CSF protein (WMD - 0.79, 95%CI [-0.96 to-0.61], P < 0.001) were significantly lower in the IDI groups. Recovery time indicators were all shorter in the IDI groups, fever (SMD - 2.45, 95% CI [-3.55 to-1.35], P < 0.001), coma (SMD-3.75, 95% CI [-4.33 to-3.17], P < 0.001), and headache (SMD  - 3.06, 95% CI [- 4.05 to-2.07], P < 0.001), respectively. Higher-dose IDI was more effective than lower-dose IDI (RR 1.23, 95% CI 1.14-1.33, P < 0.001), with no significant difference in adverse reaction rate between the two (RR 0.82, 95%CI 0.43-1.56, P = 0.544).

CONCLUSION

Adjunct IDI with C anti-TB can enhance therapeutic outcomes and reduce adverse reaction rate in adult TBM patients, with higher-dose IDI showing superior efficacy. These findings highlight the potential of IDI as an adjunctive therapy in TBM management. However, more high-quality RCTs from more regions should be conducted to support our results.

TRIAL REGISTRATION

Retrospectively registered in PROSPERO  https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023388860 .

Diagnosis and management of severe pulmonary and extrapulmonary tuberculosis in critically ill patients: A mini review for clinicians

Among critically ill patients, severe pulmonary and extrapulmonary tuberculosis has high morbidity and mortality. Yet, it is a diagnostic challenge given its nonspecific clinical symptoms and signs in early stages of the disease. In addition, management of severe pulmonary and extrapulmonary tuberculosis is complicated given the high risk of drug-drug interactions, drug-disease interactions, and adverse drug reactions. To help clinicians acquire an up-to-date approach to severe tuberculosis, this paper will provide a narrative review of contemporary diagnosis and management of severe pulmonary and extrapulmonary tuberculosis in critically ill patients.

Continuous evaluation of single-dose moxifloxacin concentrations in brain extracellular fluid, cerebrospinal fluid, and plasma: a novel porcine model

BACKGROUND

Knowledge regarding CNS pharmacokinetics of moxifloxacin is limited, with unknown consequences for patients with meningitis caused by bacteria resistant to beta-lactams or caused by TB.

OBJECTIVE

(i) To develop a novel porcine model for continuous investigation of moxifloxacin concentrations within brain extracellular fluid (ECF), CSF and plasma using microdialysis, and (ii) to compare these findings to the pharmacokinetic/pharmacodynamic (PK/PD) target against TB.

METHODS

Six female pigs received an intravenous single dose of moxifloxacin (6 mg/kg) similar to the current oral treatment against TB. Subsequently, moxifloxacin concentrations were determined by microdialysis within five compartments: brain ECF (cortical and subcortical) and CSF (ventricular, cisternal and lumbar) for the following 8 hours. Data were compared to simultaneously obtained plasma samples. Chemical analysis was performed by high pressure liquid chromatography with mass spectrometry. The applied PK/PD target was defined as a maximum drug concentration (Cmax):MIC ratio >8.

RESULTS

We present a novel porcine model for continuous in vivo CNS pharmacokinetics for moxifloxacin. Cmax and AUC0-8h within brain ECF were significantly lower compared to plasma and lumbar CSF, but insignificantly different compared to ventricular and cisternal CSF. Unbound Cmax:MIC ratio across all investigated compartments ranged from 1.9 to 4.3.

CONCLUSION

A single dose of weight-adjusted moxifloxacin administered intravenously did not achieve adequate target site concentrations within the uninflamed porcine brain ECF and CSF to reach the applied TB CNS target.

High-dose, short-duration versus standard rifampicin for tuberculosis preventive treatment: a partially blinded, three-arm, non-inferiority, randomised, controlled trial

BACKGROUND

Tuberculosis preventive treatment (TPT) is a key component of tuberculosis elimination. To improve completion and reduce the burden for people and health systems, short, safe, and effective TPT regimens are needed. We aimed to compare safety and treatment completion of various doses and durations of rifampicin in people who were recommended to receive TPT.

METHODS

This partially blinded, parallel-arm, non-inferiority, randomised, controlled, phase 2b trial was done at seven university-affiliated clinics in Canada, Indonesia, and Viet Nam. Participants aged 10 years or older were included if they had an indication for TPT according to WHO guidelines for Indonesia and Viet Nam, or Canadian guidelines for Canadian sites, and a positive tuberculin skin test or interferon-γ release assay. Participants were randomly assigned (1:1:1) to receive oral rifampicin at 10 mg/kg once daily for 4 months (standard-dose group), 20 mg/kg daily for 2 months (20 mg/kg group), or 30 mg/kg daily for 2 months (30 mg/kg group). The randomisation sequence was computer generated with blocks of variable size (three, six, and nine) and stratified by country for Indonesia and Viet Nam, and by city within Canada. Participants and investigators were masked to dose in high-dose groups, but unmasked to duration in all groups. The two co-primary outcomes were safety (in the safety population, in which participants received at least one dose of the study drug) and treatment completion (in the modified intention-to-treat [mITT] population, excluding those ineligible after randomisation). Protocol-defined adverse events were defined as grade 3 or worse, or rash or allergy of any grade, judged by an independent and masked panel as possibly or probably related to the study. A margin of 4% was used to assess non-inferiority. This study is registered with ClinicalTrials.gov, NCT03988933 (active).

FINDINGS

Between Sept 1, 2019, and Sept 30, 2022, 1692 people were assessed for eligibility, 1376 were randomly assigned, and eight were excluded after randomisation. 1368 participants were included in the mITT population (454 in the standard group, 461 in the 20 mg/kg group, and 453 in the 30 mg/kg group). 589 (43%) participants were male and 779 (57%) were female. 372 (82%) in the standard-dose group, 329 (71%) in the 20 mg/kg group, and 293 (65%) in the 30 mg/kg group completed treatment. No participants in the standard-dose group, one (<1%) of 441 participants in the 20 mg/kg group, and four (1%) of 423 in the 30 mg/kg group developed grade 3 hepatotoxicity. Risk of protocol-defined adverse events was higher in the 30 mg/kg group than in the standard-dose group (adjusted risk difference 4·6% [95% CI 1·8 to 7·4]) or the 20 mg/kg group (5·1% [2·3 to 7·8]). There was no difference in the risk of adverse events between the 20 mg/kg and standard-dose groups (-0·5% [95% CI -2·4 to 1·5]; non-inferiority met). Completion was lower in the 20 mg/kg group (-7·8% [95% CI -13·6 to -2·0]) and the 30 mg/kg group (-15·4% [-21·4 to -9·4]) than in the standard-dose group.

INTERPRETATION

In this trial, 2 months of 30 mg/kg daily rifampicin had significantly worse safety and completion than 4 months of 10 mg/kg daily and 2 months of 20 mg/kg daily (the latter, a fully blinded comparison); we do not consider 30 mg/kg to be a good option for TPT. Rifampicin at 20 mg/kg daily for 2 months was as safe as standard treatment, but with lower completion. This difference remains unexplained.

FUNDING

Canadian Institutes of Health Research.

Predicting cerebral infarction in tuberculous meningitis and its prognostic significance

Aim: Tuberculous meningitis (TBM) often causes cerebral infarction, but its predictive factors are not well understood. Methods: Patients aged ≥13 years admitted with TBM were enrolled prospectively. Cerebral infarction was diagnosed using magnetic resonance imaging. Results: Of 186 patients, 80 (43%) had infarction. Most infarctions were multiple and located in the cortical areas, basal ganglia and subcortical regions. Independent predictors of infarction at admission included high blood pressure, short illness duration, low Glasgow coma scale and hydrocephalus. Neuroimaging inflammation signs, cerebrospinal fluid analysis abnormalities and pre-existing cardiovascular risks did not predict infarction. In-hospital mortality was higher in TBM with infarction, particularly in those with advanced TBM (stage 3). Conclusion: Baseline parameters of raised intracranial pressure predict cerebral infarction in TBM.

Clinical research progress on intrathecal glucocorticoids in the treatment of infections: A review

In some infectious diseases, pathogenic microorganisms can directly or indirectly cause significant inflammatory reactions in the central nervous system, leading to severe neurological dysfunction, such as suppurative meningitis, tuberculous meningitis, and febrile infections. related epilepsy syndrome, etc. In these diseases, adjuvant administration of glucocorticoids is necessary to inhibit the release of proinflammatory cytokines, and intrathecal administration can deliver the drug more directly to the target. In this article, the authors studied intrathecal glucocorticoids for the treatment of infectious inflammatory reactions in terms of pharmacological effects and mechanisms, pharmacokinetics, clinical application, and safety. The authors concluded that the article could help provide new treatment strategies for infectious diseases.

Disease spectrum and prognostic factors in patients treated for tuberculous meningitis in Shaanxi province, China

Background

Tuberculous meningitis (TBM) is the most severe form of tuberculosis (TB) and can be difficult to diagnose and treat. We aimed to describe the clinical presentation, diagnosis, disease spectrum, outcome, and prognostic factors of patients treated for TBM in China.

Methods

A multicenter retrospective study was conducted from 2009 to 2019 enrolling all presumptive TBM patients referred to Xijing tertiary Hospital from 27 referral centers in and around Shaanxi province, China. Patients with clinical features suggestive of TBM (abnormal CSF parameters) were included in the study if they had adequate baseline information to be classified as "confirmed," "probable," or "possible" TBM according to international consensus TBM criteria and remained in follow-up. Patients with a confirmed alternative diagnosis or severe immune compromise were excluded. Clinical presentation, central nervous system imaging, cerebrospinal fluid (CSF) results, TBM score, and outcome-assessed using the modified Barthel disability index-were recorded and compared.

Findings

A total of 341 presumptive TBM patients met selection criteria; 63 confirmed TBM (25 culture positive, 42 Xpert-MTB/RIF positive), 66 probable TBM, 163 possible TBM, and 49 "not TBM." Death was associated with BMRC grade III (OR = 5.172; 95%CI: 2.298-11.641), TBM score ≥ 15 (OR = 3.843; 95%CI: 1.372-10.761), age > 60 years (OR = 3.566; 95%CI: 1.022-12.442), and CSF neutrophil ratio ≥ 25% (OR = 2.298; 95%CI: 1.027-5.139). Among those with confirmed TBM, nearly one-third (17/63, 27.0%) had a TBM score < 12; these patients exhibited less classic meningitis symptoms and signs and had better outcomes compared with those with a TBM score ≥ 12. In this group, signs of disseminated/miliary TB (OR = 12.427; 95%CI: 1.138-135.758) and a higher TBM score (≥15, OR = 8.437; 95%CI: 1.328-53.585) were most strongly associated with death.

Conclusion

TBM patients who are older (>60 years) have higher TBM scores or CSF neutrophil ratios, have signs of disseminated/miliary TB, and are at greatest risk of death. In general, more effort needs to be done to improve early diagnosis and treatment outcome in TBM patients.

Potential of Neuroinflammation-Modulating Strategies in Tuberculous Meningitis: Targeting Microglia

Tuberculous meningitis (TBM) is the most severe complication of tuberculosis (TB) and is associated with high rates of disability and mortality. Mycobacterium tuberculosis (M. tb), the infectious agent of TB, disseminates from the respiratory epithelium, breaks through the blood-brain barrier, and establishes a primary infection in the meninges. Microglia are the core of the immune network in the central nervous system (CNS) and interact with glial cells and neurons to fight against harmful pathogens and maintain homeostasis in the brain through pleiotropic functions. However, M. tb directly infects microglia and resides in them as the primary host for bacillus infections. Largely, microglial activation slows disease progression. The non-productive inflammatory response that initiates the secretion of pro-inflammatory cytokines and chemokines may be neurotoxic and aggravate tissue injuries based on damages caused by M. tb. Host-directed therapy (HDT) is an emerging strategy for modulating host immune responses against diverse diseases. Recent studies have shown that HDT can control neuroinflammation in TBM and act as an adjunct therapy to antibiotic treatment. In this review, we discuss the diverse roles of microglia in TBM and potential host-directed TB therapies that target microglia to treat TBM. We also discuss the limitations of applying each HDT and suggest a course of action for the near future.

Role of MicroRNAs as post transcription regulators of matrix metalloproteinases and their association in tuberculous meningitis

Matrix metalloproteinases (MMPs) have a role in driving neuroinflammation in infectious as well as non-infectious diseases; however, recent reports have potentiated the role of microRNAs in regulating MMPs at post-transcriptional levels, leading to dysregulation of crucial MMP functions like tissue remodelling, blood brain barrier integrity, etc. In present study, microRNAs regulating MMPs (MMP2 and MMP3) were selected from database search followed by literature support. Expression of these microRNAs i.e., hsa-miR-495-3p, hsa-miR-132-3p and hsa-miR-21-5p was assessed by RT-PCR and the protein levels of MMPs were assessed by ELISA in the cerebrospinal fluid (CSF) of tuberculous meningitis (TBM) patients, healthy controls (HC) and non-infectious neuroinflammatory disease (NID) patients. The expression of hsa-miR-495-3p and hsa-miR-132-3p showed downregulation in TBM while hsa-miR-21-5p was overexpressed as compared to healthy controls. Moreover, MMP levels were found to be deranged with a significant increase in MMP3 levels in the TBM and NID patients compared to HC group. These observations highlight dysregulated microRNAs (hsa-miR-495-3p, hsa-miR-21-5p and hsa-miR-132-3p) levels might impair the levels of MMPs (MMP2 and MMP3) leading to neuroinflammation in TBM and NID population. These findings can further be applied to target these microRNAs for developing newer treatment modalities for better complication management.

Large cerebral tuberculoma

Here, we are presenting a young previous healthy child with seizures and right side hemiparesis for 6 months. After blood work and an MRI brain with IV contrast, it is confirmed that the child has large cerebral tuberculoma. The child is improved with TB treatment and surgery.

Cell-free DNA blood test for the diagnosis of pediatric tuberculous meningitis

Pediatric tuberculous meningitis (TBM) is a severe form of tuberculosis that may present in children. The current diagnostic methods may have a limited impact on initial clinical decision-making. We present three children with tuberculous meningitis who had Mycobacterium tuberculosis complex cell-free DNA (cfDNA) detected in their blood within three days of sampling. Our cases described here illustrate for the first time the potential role of cfDNA blood tests in the rapid diagnosis of TBM.

The discrimination between autoimmune glial fibrillary acidic protein astrocytopathy and tuberculous meningitis

OBJECTIVE

The differential diagnosis between autoimmune glial fibrillary acidic protein astrocytopathy (AGFAPA) mimicking tuberculous meningitis and tuberculous meningitis (TBM) remains challenging in clinical practice. This study aims to identify the clinical, laboratory parameters, and clinical score systems that may be helpful in differentiating AGFAPA from TBM.

METHOD

Overall 22 AGFAPA patients who were initially misdiagnosed as TBM (AGFAPA-TBM) and 30 confirmed TBM patients were included. The clinical, laboratory, imaging parameters, Thwaites systems, and Lancet consensus scoring systems (LCSS) of all patients were reviewed. Logistic regression was employed to establish a diagnostic formula to differentiate AGFAPA-TBM from TBM. The receiver operating characteristic (ROC) curve was applied to determine the best diagnostic critical point of the formula.

RESULTS

Urinary retention was more frequent in AGFAPA-TBM patients (72.7% vs 33.3%, p = 0.012). A significantly lower ratio of T-SPOT. TB was noted in AGFAPA-TBM patients (9.1% vs 82.1%, p < 0.001). We found the LCSS was able to differentiate AGFAPA-TBM from TBM (AUC value 0.918, 95% CI=0.897-0.924). Furthermore, we set up a new scoring system with three variables: urinary retention, T-SPOT. TB, and cerebral imaging criteria in LCSS. The proposed diagnostic score ranges from -8 to 2, and a score of ≥ 0 was suggestive of AGFAPA-TBM (AUC value 0.938, 95% CI=0.878-0.951).

CONCLUSIONS

This study is the first to evaluate the Thwaites system and LCSS in AGFAPA-TBM and TBM. We provide an alternative diagnostic formula to differentiate AGFAPA-TBM from TBM and suggest testing for GFAP antibodies to avoid misdiagnosis when this scoring system meets AGFAPA-TBM.

Therapeutic developments for tuberculosis and nontuberculous mycobacterial lung disease

Tuberculosis (TB) drug discovery and development has undergone nothing short of a revolution over the past 20 years. Successful public-private partnerships and sustained funding have delivered a much-improved understanding of mycobacterial disease biology and pharmacology and a healthy pipeline that can tolerate inevitable attrition. Preclinical and clinical development has evolved from decade-old concepts to adaptive designs that permit rapid evaluation of regimens that might greatly shorten treatment duration over the next decade. But the past 20 years also saw the rise of a fatal and difficult-to-cure lung disease caused by nontuberculous mycobacteria (NTM), for which the drug development pipeline is nearly empty. Here, we discuss the similarities and differences between TB and NTM lung diseases, compare the preclinical and clinical advances, and identify major knowledge gaps and areas of cross-fertilization. We argue that applying paradigms and networks that have proved successful for TB, from basic research to clinical trials, will help to populate the pipeline and accelerate curative regimen development for NTM disease.

Single-cell transcriptome reveals highly complement activated microglia cells in association with pediatric tuberculous meningitis

Background

Tuberculous meningitis (TBM) is a devastating form of tuberculosis (TB) causing high mortality and disability. TBM arises due to immune dysregulation, but the underlying immune mechanisms are unclear.

Methods

We performed single-cell RNA sequencing on peripheral blood mononuclear cells (PBMCs) and cerebrospinal fluid (CSF) cells isolated from children (n=6) with TBM using 10 xGenomics platform. We used unsupervised clustering of cells and cluster visualization based on the gene expression profiles, and validated the protein and cytokines by ELISA analysis.

Results

We revealed for the first time 33 monocyte populations across the CSF cells and PBMCs of children with TBM. Within these populations, we saw that CD4_C04 cells with Th17 and Th1 phenotypes and Macro_C01 cells with a microglia phenotype, were enriched in the CSF. Lineage tracking analysis of monocyte populations revealed myeloid cell populations, as well as subsets of CD4 and CD8 T-cell populations with distinct effector functions. Importantly, we discovered that complement-activated microglial Macro_C01 cells are associated with a neuroinflammatory response that leads to persistent meningitis. Consistently, we saw an increase in complement protein (C1Q), inflammatory markers (CRP) and inflammatory factor (TNF-α and IL-6) in CSF cells but not blood. Finally, we inferred that Macro_C01 cells recruit CD4_C04 cells through CXCL16/CXCR6.

Discussion

We proposed that the microglial Macro_C01 subset activates complement and interacts with the CD4_C04 cell subset to amplify inflammatory signals, which could potentially contribute to augment inflammatory signals, resulting in hyperinflammation and an immune response elicited by Mtb-infected tissues.

Discovering common pathogenetic processes between tuberculosis and COVID-19 by bioinformatics and system biology approach

Background

SARS-CoV-2, the cause of the COVID-19 pandemic, poses a significant threat to humanity. Individuals with pulmonary tuberculosis (PTB) are at increased risk of developing severe COVID-19, due to long-term lung damage that heightens their susceptibility to full-blown disease.

Methods

Three COVID-19 datasets (GSE157103, GSE166253, and GSE171110) and one PTB dataset (GSE83456) were obtained from the Gene Expression Omnibus databases. Subsequently, data were subjected to weighted gene co-expression network analysis(WGCNA)followed by functional enrichment analysis using Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway databases. These analyses revealed two overlapping disease-specific modules, each comprising co-regulated genes with potentially related biological functions. Using Cytoscape, we visualised the interaction network containing common disease-related genes found within the intersection between modules and predicted transcription factors (TFs). Real-time qPCR was conducted to quantify expression levels of these genes in blood samples from COVID-19 and PTB patients. Finally, DisGeNET and the Drug Signatures database were employed to analyze these common genes, unveiling their connections to clinical disease features and potential drug treatments.

Results

Examination of the overlap between COVID-19 and PTB gene modules unveiled 11 common genes. Functional enrichment analyses using KEGG and GO shed light on potential functional relationships among these genes, providing insights into their potential roles in the heightened mortality of PTB patients due to SARS-CoV-2 infection. Furthermore, results of various bioinformatics-based analyses of common TFs and target genes led to identification of shared pathways and therapeutic targets for PTB patients with COVID-19, along with potential drug treatments for these patients.

Conclusion

Our results unveiled a potential biological connection between COVID-19 and PTB, as supported by results of functional enrichment analysis that highlighted potential biological processes and signaling pathways shared by both diseases. Building on these findings, we propose potential drug treatments for PTB patients with COVID-19, pending verification of drug safety and efficacy through laboratory and multicentre studies before clinical use.