Tuberculous meningitis

Nos2-/- mice infected with M. tuberculosis develop neurobehavioral changes and immunopathology mimicking human central nervous system tuberculosis

BACKGROUND

Understanding the pathophysiology of central nervous system tuberculosis (CNS-TB) is hampered by the lack of a good pre-clinical model that mirrors the human CNS-TB infection. We developed a murine CNS-TB model that demonstrates neurobehavioral changes with similar immunopathology with human CNS-TB.

METHODS

We injected two Mycobacterium tuberculosis (M.tb) strains, H37Rv and CDC1551, respectively, into two mouse strains, C3HeB/FeJ and Nos2-/- mice, either into the third ventricle or intravenous. We compared the neurological symptoms, histopathological changes and levels of adhesion molecules, chemokines, and inflammatory cytokines in the brain induced by the infections through different routes in different strains.

RESULTS

Intra-cerebroventricular infection of Nos2-/- mice with M.tb led to development of neurological signs and more severe brain granulomas compared to C3HeB/FeJ mice. Compared with CDC1551 M.tb, H37Rv M.tb infection resulted in a higher neurobehavioral score and earlier mortality. Intra-cerebroventricular infection caused necrotic neutrophil-dominated pyogranulomas in the brain relative to intravenous infection which resulted in disseminated granulomas and mycobacteraemia. Histologically, intra-cerebroventricular infection of Nos2-/- mice with M.tb resembled human CNS-TB brain biopsy specimens. H37Rv intra-cerebroventricular infected mice demonstrated higher brain concentrations of inflammatory cytokines, chemokines and adhesion molecule ICAM-1 than H37Rv intravenous-infected mice.

CONCLUSIONS

Intra-cerebroventricular infection of Nos2-/- mice with H37Rv creates a murine CNS-TB model that resembled human CNS-TB immunopathology, exhibiting the worst neurobehavioral score with a high and early mortality reflecting disease severity and its associated neurological morbidity. Our murine CNS-TB model serves as a pre-clinical platform to dissect host-pathogen interactions and evaluate therapeutic agents for CNS-TB.

Sequential Intravenous-Oral Therapy for Pediatric Streptococcus anginosus Intracranial Infections

Background

Streptococcus anginosus group is a common cause of pediatric intracranial infections but treatment recommendations, including use of oral therapy, are poorly defined.

Methods

We performed a retrospective review from 2004 to 2019 of all patients with S anginosus group pyogenic intracranial infections at Children's Hospital Colorado, highlighting patients transitioned to oral therapy. The primary endpoint was worsening infection necessitating intravenous antibiotics or a source control procedure after transition to oral therapy.

Results

Of 107 patients with S anginosus intracranial infections, 61 were transitioned to exclusive oral therapy after a median intravenous duration of 37 days, overwhelmingly with a levofloxacin-based regimen. Only 1 treatment failure was noted in a patient who did not fill their prescription. Patients with epidural infections were more likely to be transitioned to oral therapy within the first 28 days of treatment (defined as "early"). Patients with parenchymal infections, bacteremia, co-pathogens, higher inflammatory markers, and requiring >1 source control procedure were less likely to be transitioned early to oral therapy. Complications of a central catheter and/or intravenous medications contributed to 56% of oral transitions.

Conclusions

Levofloxacin-based oral regimens were effective and well tolerated. Patients with less severe infections were more likely to be transitioned early to oral therapy. Criteria for transitioning patients to oral antibiotics for intracranial infections should be established to minimize risks inherent with central catheters.

Protection against tuberculosis by Bacillus Calmette-Guérin (BCG) vaccination: A historical perspective

Bacillus Calmette-Guérin (BCG) was developed exactly 100 years ago, and it is still the only licensed tuberculosis (TB) vaccine and the most frequently administered of all vaccines worldwide. Despite universal vaccination policies in TB-endemic settings, the burden of TB remains high. Although BCG protects against Mycobacterium tuberculosis infection and TB disease, the level of protection varies greatly between age groups and settings. In this review, we present a historical perspective and describe the evidence for BCG's ability to protect against TB as well as the factors that influence protection. We also present the immunological mechanisms through which BCG vaccination induces protection, focusing on T cell, B cell, and innate immunity. Finally, we discuss several possibilities to boost BCG's efficacy, including alternative vaccination routes, BCG revaccination, and use of recombinant BCG vaccines, and describe the knowledge gaps that exist with respect to BCG's protection against TB.

The Impact of Hyponatremia on the Severity of Childhood Tuberculous Meningitis

Introduction: Hyponatremia and/or hypoglycorrhachia are commonly encountered biochemical derangements during the acute stage of childhood tuberculous meningitis (TBM). Few studies have explored the correlation between these derangements and the staging of TBM disease (severity), or explored their role as biomarkers for vascular ischemic events, hydrocephalus, or seizures. Methods: We aimed to identify the prevalence and the correlation between serum hyponatremia (mild, moderate and severe) and/or hypoglycorrhachia in relation to clinical TBM features such as stage of disease, seizures and stroke in children diagnosed with definite and probable TBM, between 1985 and 2015, at Tygerberg Hospital, Cape town, South Africa. Results: The prevalence of hyponatremia was 344 out of 481 (71.5%) patients; 169 (49.1%) had mild hyponatremia, 146 (42.4%) moderate hyponatremia and 29 (8.4%) severe hyponatremia. Children with severe hyponatremia had higher frequency of stroke [odds ratio (OR) 4.36, 95% confidence interval (CI) 1.24-15.35; p = 0.01], brainstem dysfunction (OR 7.37, 95% CI 2.92-18.61; p < 0.01), cranial nerve palsies (OR 2.48, 95% CI 1.04-5.91; p = 0.04) and non-communicating hydrocephalus (OR 2.66, 95% CI 1.09-6.44; p = 0.03). Children with moderate hyponatremia and mild hyponatremia compared to those without hyponatremia similarly were more likely to exhibit signs of brainstem dysfunction (OR 1.91, 95% CI 1.11-3.28; p = 0.02) and hydrocephalus (OR 3.18, 95% CI 1.25-8.09; p = 0.01), respectively. On multivariable analysis only brainstem dysfunction was significantly associated with severe hyponatremia [adjusted odds ratio (aOR) 4.46, 95% CI 1.62-12.30; p < 0.01]. Children with hypoglycorrhachia compared to normoglycorrhachia were more likely to have had longer symptom duration prior to admission (OR 1.87, 95% CI 1.09-3.20; p = 0.02), non-communicating hydrocephalus (OR 1.64, 95% CI 0.99-2.71; p = 0.05), higher cerebrospinal white cell counts (OR 3.00, 95% CI 1.47-6.12; p < 0.01) and higher CSF protein concentrations (OR 2.51, 95% CI 1.49-4.20; p < 0.01). On multivariable analysis raised CSF protein concentration >1 g/L was significantly associated with hypoglycorrhachia (aOR 2.52, 95% CI 1.44-4.40; p < 0.01). Death rates did not differ by sodium level category or presence of hypoglycorrachia, however an increasing trend of children that had demised was noted the more severe the sodium category. Conclusion: Hyponatremia and/or hypoglycorrhachia occur in more than two-thirds of children with TBM. Severe TBM disease complications such as brainstem dysfunction was associated with moderate hyponatremia, while severe hyponatremia was associated with brainstem dysfunction, stroke, cranial nerve palsies and non-communicating hydrocephalus. Cerebrospinal fluid (CSF) glucose depletion correlated with non-communicating hydrocephalus and increased CSF inflammation.

Case report: Depressive disorder with peripartum onset camouflages suspected intracranial tuberculoma

BACKGROUND

Co-occuring psychological symptoms and rare medical illnesses like intracranial tuberculoma add difficulties in diagnosing and treatment. The present report discussed a rare case of a young woman with tuberculoma and depressive disorder with peripartum onset.

CASE PRESENTATION

The patient was a 22-year-old woman. She underwent a cesarean section due to premature rupture of the membrane. She had developed behavioral changes for 3 months before admission and had been brought to general practitioner for several times during pregnancy. Her symptoms worsen after she underwent a cesarean section. She refused to answer doctor's and family's questions and she showed symptoms of depression. She was diagnosed with depressive disorder with peripartum onset and treated according to her diagnosis. However, she also experienced intermittent headaches which lead to suspicion that there was an organic cause for her complaints. Computed tomography (CT) was done and revealed suspected intracranial tuberculoma and meningitis. She died due to respiratory distress before she got adequate treatment for her illnesses.

CONCLUSION

The possibility of neurocognitive disorder due to infection such as intracranial tuberculoma should be considered as an additional diagnosis (co-occuring disease) or differential diagnosis in people who develop psychiatric symptoms, especially in areas with high tuberculosis incidence.

Pharmacokinetics and safety/tolerability of isoniazid, rifampicin and pyrazinamide in children and adolescents treated for tuberculous meningitis

OBJECTIVE

To assess the pharmacokinetics and safety/tolerability of isoniazid, rifampicin and pyrazinamide in children and adolescents with tuberculous meningitis (TBM).

DESIGN

Prospective observational pharmacokinetic study with an exploratory pharmacokinetic/pharmacodynamic analysis.

SETTING

Hasan Sadikin Hospital, Bandung, Indonesia.

PATIENTS

Individuals aged 0-18 years clinically diagnosed with TBM and receiving first-line anti-tuberculosis drug dosages according to revised WHO-recommended treatment guidelines.

INTERVENTIONS

Plasma and cerebrospinal fluid (CSF) concentrations of isoniazid, rifampicin and pyrazinamide were assessed on days 2 and 10 of treatment.

MAIN OUTCOME MEASURES

Plasma exposures during the daily dosing interval (AUC_0-24), peak plasma concentrations (C_max) and CSF concentrations.

RESULTS

Among 20 eligible patients, geometric mean AUC_0-24 of isoniazid, rifampicin and pyrazinamide was 18.5, 66.9 and 315.5 hour∙mg/L on day 2; and 14.5, 71.8 and 328.4 hour∙mg/L on day 10, respectively. Large interindividual variabilities were observed in AUC_0-24 and C_max of all drugs. All patients had suboptimal rifampicin AUC_0-24 for TBM treatment indication and very low rifampicin CSF concentrations. Four patients developed grade 2-3 drug-induced liver injury (DILI) within the first 4 weeks of treatment, in whom anti-tuberculosis drugs were temporarily stopped, and no DILI recurred after reintroduction of rifampicin and isoniazid. AUC_0-24 of isoniazid, rifampicin and pyrazinamide along with C_max of isoniazid and pyrazinamide on day 10 were higher in patients who developed DILI than those without DILI (p<0.05).

CONCLUSION

Higher rifampicin doses are strongly warranted in treatment of children and adolescents with TBM. The association between higher plasma concentrations of isoniazid, rifampicin and pyrazinamide and the development of DILI needs confirmatory studies.

Tuberculous Meningitis in Children: A Forgotten Public Health Emergency

Tuberculous meningitis (TBM) remains a major cause of morbidity and mortality in children with tuberculosis (TB), yet there are currently no estimates of the global burden of pediatric TBM. Due to frequent non-specific clinical presentation and limited and inadequate diagnostic tests, children with TBM are often diagnosed late or die undiagnosed. Even when diagnosed and treated, 20% of children with TBM die. Of survivors, the majority have substantial neurological disability with significant negative impact on children and their families. Surveillance data on this devastating form of TB can help to quantify the contribution of TBM to the overall burden, morbidity and mortality of TB in children and the epidemiology of TB more broadly. Pediatric TBM usually occurs shortly after primary infection with Mycobacterium tuberculosis and reflects ongoing TB transmission to children. In this article we explain the public health importance of pediatric TBM, discuss the epidemiology within the context of overall TB control and health system functioning and the limitations of current surveillance strategies. We provide a clear rationale for the benefit of improved surveillance of pediatric TBM using a TB care cascade framework to support monitoring and evaluation of pediatric TB, and TB control more broadly. Considering the public health implications of a diagnosis of TBM in children, we provide recommendations to strengthen pediatric TBM surveillance and outline how improved surveillance can help us identify opportunities for prevention, earlier diagnosis and improved care to minimize the impact of TBM on children globally.

Tuberculous Meningitis in Children: Reducing the Burden of Death and Disability

Tuberculous meningitis disproportionately affects young children. As the most devastating form of tuberculosis, it is associated with unacceptably high rates of mortality and morbidity even if treated. Challenging to diagnose and treat, tuberculous meningitis commonly causes long-term neurodisability in those who do survive. There remains an urgent need for strengthened surveillance, improved rapid diagnostics technology, optimised anti-tuberculosis drug therapy, investigation of new host-directed therapy, and further research on long-term functional and neurodevelopmental outcomes to allow targeted intervention. This review focuses on the neglected field of paediatric tuberculous meningitis and bridges current clinical gaps with research questions to improve outcomes from this crippling disease.

Tuberculostearic acid, a potential parameter for scoring system construction for tuberculous meningitis diagnosis

Background

This study aimed to validate the value of tuberculostearic acid (TBSA) whether it could implicate the existence of Mycobacterium tuberculosis (Mtb) and assist for the clinical diagnosis of tuberculous meningitis (TBM).

Methods

The patient's cerebrospinal fluid (CSF) specimen was collected through the lumbar puncture and detected for TBSA with gas chromatography/mass spectrometry. At the same time, gold standard tests, i.e., CSF direct culture, CSF smear microscopy, or nucleic acid amplification tests, for Mtb were routinely performed. Furthermore, we evaluated all patients by the Lancet consensus scoring system, which classifies suspected patients to "Definite (depend on gold standard results only)," "Probable (>10 pts without imaging or >12 pts with imaging information)," "Possible (6-9 pts without imaging or 6-11 pts with imaging)," and "Not (<6 pts or with alternative diagnoses)" TBM.

Results

In total, 140 patients were admitted for our study included 27 confirmed TBM patients and 50 TBSA-positive patients. Sensitivity (0.7407, confidence interval [CI] 95%: 0.5372-0.8889) and specificity (0.7345, CI 95%: 0.6432-0.8132) were calculated. The Lancet consensus scoring system was also applied to evaluate the possibility of TBM in suspected patients, finding that TBSA-positive patients showed a similar grouping distribution as the definite TBM patients.

Conclusions

Our study implicates that the prospective utilization of TBSA is worth combining into a scoring system for characterizing the features of Mtb, showing a great potential of TBM diagnosis by TBSA in future.

High-dose rifampicin for the treatment of tuberculous meningitis: a meta-analysis of randomized controlled trials

WHAT IS KNOWN AND OBJECTIVE

Tuberculous meningitis (TBM) is one of the most serious types of extrapulmonary tuberculosis and has caused distress to human. Effective treatment is particularly important. The aim of this meta-analysis is to compare the efficacy of high-dose and standard-dose rifampicin.

METHODS

Databases including PubMed, Web of Science, Embase, Scopus and the Cochrane Library databases were electronically searched to identify randomized controlled trials that reported high-dose rifampicin in treatment of patients with TBM. The retrieval time is limited from inception to June 2021. Two reviewers independently screened literature, extracted data and assessed risk bias of included studies. Meta-analysis was performed by using STATA 12.0 software.

RESULTS AND DISCUSSION

A total of 12 studies involving 1596 patients were included. The meta-analysis results showed no significant differences in 6-month mortality, 9-month mortality, Grade I-II AE, Grade III-V AE, hepatotoxicity, hepatotoxicity Grade I-II and cardiologic events between high-dose rifampicin (or high-dose rifampicin plus moxifloxacin or levofloxacin) and standard-dose groups. The log(C_max ) (WMD 0.69, 95%CI 0.59-0.79, p 0.001) and log(AUC_0-24h ) (WMD 0.79, 95%CI 0.71-0.88, p 0.001) were higher with high-dose rifampicin. Subgroup analysis revealed the rise of log(C_max ) in high-dose rifampicin orally was consistent with intravenous administration compared with the control (WMD 0.69, 95%CI 0.66-0.73, p 0.001).

WHAT IS NEW AND CONCLUSION

High-dose rifampicin was not a protective factor for 6-month mortality, despite increased plasma C_max and AUC_0-24h . However, the above conclusions are still required to be verified through more RCTs due to the limited quantity of included studies.

Cerebrospinal fluid analysis is associated with enhancement on MRI in bacterial and tuberculous meningitis: A retrospective observational study

OBJECTIVE

Along with cerebrospinal fluid (CSF) analysis, enhancement on contrast-enhanced MRI is useful to diagnose meningitis. However, the conditions for its appearance have not been clarified. This study aimed to investigate the association between CSF parameters and enhancement on contrast-enhanced head or spinal MRI in patients with bacterial meningitis (BM) or tuberculous meningitis (TM).

METHODS

A total of 12 patients with BM and 23 patients with TM who underwent both CSF analysis and contrast-enhanced MRI were included. The correlation between CSF analysis and MRI findings has been examined using receiver operating characteristic (ROC) analysis.

RESULTS

Contrast enhancement was found in 7 and 10 patients with BM and TM, respectively. Both CSF analysis and MRI were useful to distinct between BM and TM, and the enhancement implied the severity of them. In patients with BM, higher CSF protein and lower CSF glucose were associated with enhancement on MRI, while not only CSF protein and glucose but also leukocyte and lymphocyte counts were associated with it in TM. CSF adenosine deaminase (ADA) did not show discriminant ability of the MRI findings.

CONCLUSIONS

CSF analysis is associated with enhancement on contrast-enhanced MRI both in BM and TM. Our findings indicate the importance of CSF analysis in assessing the need to perform contrast-enhanced MRI, which may be useful in diagnosis, distinction, and estimation of prognosis in those patients.

Treatment and outcome in children with tuberculous meningitis - a multi-centre Paediatric Tuberculosis Network European Trials Group study

INTRODUCTION

Currently, data on treatment, outcome, and prognostic factors in children with tuberculous meningitis (TBM) in Europe are limited. To date, most existing data on TBM originate from adult studies, or studies conducted in low-resource settings.

METHODS

Multicentre, retrospective study involving 27 paediatric healthcare institutions in nine European countries via an established paediatric TB research network, before and after the 2014 revision of WHO dosing recommendations.

RESULTS

Of 118 children, 39 (33.1%) had TBM grade 1, 68 (57.6%) grade 2 and 11 (9.3%) grade 3. Fifty-eight (49.1%) children received a standard four-drug treatment regimen; other commonly used drugs included streptomycin, prothionamide, and amikacin. Almost half of the patients (48.3%; 56/116) were admitted to intensive care unit, with a median stay of 10 (IQR 4.5-21.0) days. Of 104 children with complete outcome data, 9.6% (10/104) died, and only 47.1% (49/104) recovered fully. Main long-term sequelae included spasticity of one or more limbs and developmental delay both in 19.2% (20/104), and seizure disorder in 17.3% (18/104). Multivariate regression analyses identified microbiological confirmation of TBM, the need for neurosurgical intervention and mechanical ventilation as risk factors for unfavourable outcome.

DISCUSSION

There was considerable heterogeneity in the use of TB drugs in this cohort. Despite few children presenting with advanced disease and the study being conducted in a high-resource setting, morbidity and mortality were high. Several risk factors for poor outcome were identified, which may aid prognostic predictions in children with TBM in the future.

Optic Nerve Sheath Ultrasound for the Detection and Monitoring of Raised Intracranial Pressure in Tuberculous Meningitis

BACKGROUND

Neurological complications of tuberculous meningitis (TBM) often lead to raised intracranial pressure (ICP) resulting in high morbidity and mortality. Measurement of optic nerve sheath diameter (ONSD) by point-of-care ultrasound may aid in the identification of raised ICP in TBM.

METHODS

From June 2017 to December 2019, 107 Vietnamese adults with TBM, enrolled in the ACT HIV or LAST ACT trials (NCT03092817, NCT03100786), underwent ONSD ultrasound at ≥1 of days 0, 3, 7, 14, 21, and day ±30 after enrollment. Demographic data, TBM severity grade, HIV coinfection status, and clinical endpoints by 3 months were recorded. ONSD values were correlated with disease severity, baseline brain imaging, cerebrospinal fluid parameters, and clinical endpoints.

RESULTS

267 ONSD ultrasound scans were performed in 107 participants over the first 30 days of treatment, with measurements from 0.38-0.74 cm. Paired baseline ONSD and brain imaging were performed in 63 participants. Higher baseline ONSD was associated with more severe disease and abnormal brain imaging (abnormal imaging 0.55 cm vs 0.50 cm normal imaging, P = .01). Baseline median ONSD was significantly higher in participants who died by 3 months (0.56 cm [15/72]) versus participants who survived by 3 months (0.52 cm [57/72]) (P = .02). Median ONSD was higher at all follow-up times in participants who died by 3 months.

CONCLUSIONS

Higher ONSD was associated with increased disease severity, brain imaging abnormalities, and increased death by 3 months. ONSD ultrasound has a potential role as a noninvasive, affordable bedside tool for predicting brain pathology and death in TBM.

Direct economic burden of patients with tuberculous meningitis in western China

OBJECTIVE

To estimate the direct economic burden of tuberculous meningitis (TBM) in China for the first time.

METHODS

Patients who were first diagnosed with TBM from December 2015 to December 2018 in Western China Hospital were enrolled. We retrospectively collected data on demographic and clinical features, resource utilization, costs, and long-term outcomes. The patients were followed up for 15-53 months. We performed a cost-of-illness study and analyzed the cost contributors with a generalized linear model.

RESULTS

In total, the cases of 154 TBM patients (95 males, 59 females, aged 14-82 years) were reviewed. The average total direct cost per person was USD (United States dollars) 9,484 (range 1,822-67,285), with a mean direct medical cost of USD 8,901 (range 1,189-67,049). The average inpatient cost and drug cost after discharge were USD 6,837 (range 845-52,921) and USD 1,967 (range 0-60,423), respectively. The mean direct nonmedical cost was USD 583 (range 33-3,817), which accounted for 6.2% of the total direct cost. The average length of stay (LOS) in hospital was 25.0 days (range 6-152). A total of 117 of the patients (76.0%) had good outcomes (mRS = 0-2). There was no significant difference in the costs, LOS, or outcomes between rural and urban patients. Contributors to total direct cost were definite TBM, fever, coma, seizures, multidrug resistance, hydrocephalus, and poor long-term outcome.

CONCLUSIONS

Although the accessibility of medical resources in remote and rural regions has significantly improved in China, the cost of TBM imposes a catastrophic burden on patients.

Hydrocephalus in Low and Middle-Income Countries - Progress and Challenges

Hydrocephalus remains one of the most commonly treated neurosurgical conditions worldwide. Caring for patients with hydrocephalus requires infrastructure and political support and initiative; these are often difficult to obtain in low- and middle-income countries (LMICs). Some innovations that have arisen in LMICs have traveled up the financial gradient to high-income countries, such as the combination of endoscopic third ventriculostomy with choroid plexus coagulation to manage hydrocephalus. The development of neuro-endoscopy has played a major role in managing hydrocephalus worldwide; however, LMICs still face specific challenges, such as limited access to shunt hardware, a disproportionately high incidence of post-infectious hydrocephalus, unique microbiological spectra, and often poor access to follow-up care and neuroimaging. This has received increased attention since the Lancet Commission on Global Surgery. The goal of improving access to quality neurosurgical care through various initiatives in LMICs will be discussed in this manuscript. The need for neurosurgeons continues to grow in LMICs, where better access to neurosurgical care, adequate neurosurgical training and political support, and patient education are needed to improve the quality of life for patients with common neurosurgical conditions. Despite these challenges, treating hydrocephalus remains a worthwhile endeavor for many patients.

Paradoxical manifestations during tuberculous meningitis treatment among HIV-negative patients: a retrospective descriptive study and literature review

BACKGROUND

Tuberculous meningitis (TBM) is the most frequent, severe, and disabling form of central nervous system (CNS) tuberculosis (TB). TBM paradoxical manifestations are characterized by clinical or paraclinical worsening after 1 month of effective anti-TB treatment in patients who initially responded to treatment despite the use of adjunctive corticosteroids.

METHODS

Retrospective descriptive study of consecutive HIV-negative adult patients (≥ 18 years) with definitive TBM who developed a paradoxical manifestation following anti-TB in a tertiary-care hospital in Mexico from 2009 to 2019; we also conducted a literature review of published cases/series of paradoxical manifestations in HIV-negative patients from 1980 to 2020.

RESULTS

We detected 84 cases of definitive TBM; 55 (68.7%) HIV-negative patients and 29 (36.3%) HIV-infected patients. Among HIV-negative patients, four (7.3%), three female and one male (19-49 years old), developed a paradoxical manifestation within 4-14 weeks following treatment initiation despite receiving adequate corticosteroid doses; Mycobacterium bovis was isolated from the cerebrospinal fluid of three cases and Mycobacterium tuberculosis in one more. Two patients developed vasculopathy-related cerebral infarctions, one severe basilar meningitis, and hydrocephalus, one more a tuberculoma. Two were treated with intravenous cyclophosphamide, and two with steroids. One of the patients treated with steroids died; patients who received cyclophosphamide had a good clinical response.

CONCLUSIONS

This case series illustrates the diverse clinical/radiologic paradoxical manifestations of TBM in HIV-negative patients. Cyclophosphamide may be safe and effective in treating TBM-associated paradoxical manifestations. Specific diagnostic and care protocols for these patients are needed.

Intrathecal therapy for tuberculous meningitis: propensity-matched cohort study

OBJECTIVE

The study aimed to determine the safety and efficacy of intrathecally administered isoniazid (INH) and prednisolone in addition to systemic anti-TB therapy and compare it with systemic anti-TB therapy alone in adult patients with tuberculous meningitis (TBM).

METHODS

In this retrospective study, patients were categorized into two groups: Group A patients received systematic anti-TB therapy alone, Group B patients received IT INH (50 mg) and prednisolone (25 mg) twice a week together with the same standard systemic anti-TB therapy as Group A, in addition to the standard systemic anti-TB therapy. Functional outcomes were compared between the two groups in a prosperity-matched cohort using propensity score matching (PSM) method.

RESULTS

A total of 198 patients with TBM were enrolled. After PSM, 30 patients from each group were analyzed, so that there was no significant difference in the characteristics of the two groups. Mortality at follow-up was significantly lower among patients receiving additional IT therapy (4/30, 13.3%) compared with matched patients receiving systemic anti-TB therapy alone (11/30, 36.7%, P value = 0.037).

CONCLUSIONS

In this propensity score-matched cohort, the addition of IT INH and prednisolone to systemic anti-TB therapy could be effective for the better outcome among adult TBM patients. Further large-scale, prospective, and randomized controlled trials are warranted to the best timing and indication of IT therapy.

A statistical analysis plan for the Adjunctive Corticosteroids for Tuberculous meningitis in HIV-positive adults (ACT HIV) clinical trial

TBM is the most severe form of tuberculosis. Clinical trial data are required to provide an evidence base for adjunctive dexamethasone in HIV-positive individuals with TBM, and to guide clinical practice. This document details the planned analyses at 12 months post randomisation for the ACT HIV clinical trial (NCT03092817); 'a randomised double-blind placebo-controlled trial of adjunctive dexamethasone for the treatment of HIV co-infected adults with tuberculous meningitis (TBM)'. The primary endpoint of the ACT HIV trial is death (from any cause) over the first 12 months after randomisation. This statistical analysis plan expands upon and updates the analysis plan outlined in the published study protocol.

Presentation, Clinical Characteristics, and Treatment Outcomes among Tuberculous Meningitis Patients with and Without HIV Infection at Vajira Hospital, Thailand: A Retrospective Cohort Study

To compare the characteristics, presentation, investigations, and outcomes in tuberculous meningitis (TBM) patients with and without human immunodeficiency virus (HIV) coinfection. A retrospective cohort study was conducted on adult (age > 18 years) patients whose final diagnosis was TBM and who were treated at Vajira Hospital, Navamindradhiraj University, Thailand, between January 2005 and December 2016. A final total of 174 individuals were included in the study. Of these, 97 (55.75%) were HIV positive. Treatment was successful in 53 (30.5%) individuals. In HIV-infected TBM patients, there were higher proportions of patients who were younger in age (≤40 years), patients with a low body mass index, history of previous tuberculosis infection, or hepatitis C virus coinfection. A successful treatment outcome rate was lower in HIV-infected TBM patients than in HIV-uninfected TBM patients. Since HIV infection decreases the chance of successful treatment outcomes of TBM patients, future studies are needed to determine the clinical indicators for poorer survival outcomes in HIV-positive TBM patients.

Uncommon presentation of craniospinal tuberculosis

Tuberculosis (TB) is a bacterial infection with multisystem presentations. Involvement of the central nervous system (CNS) is considered the most lethal form among all types. In addition to possible fatality, CNS TB has serious neurological sequelae. These morbidity issues along with diagnostic challenges doubles the clinical burden. In recent years, there have been improvements in diagnostic sensitivity and specificity due to advances in technology. Herein, we report an atypical case of a patient with TB who presented to our department and discuss the flow of the diagnostic workup.

Hyponatremia in tuberculous meningitis: A systematic review and meta-analysis

BACKGROUND

Tuberculous meningitis (TBM), manifests as the most severe involvement of the nervous system by Mycobacterium tuberculosis, it has a high mortality rate and a spectrum of systemic and neurological complications that can lead to debilitating or fatal sequelae, whereas hyponatremia is the commonly encountered life-threatening electrolyte disturbance. Thus, our study aimed to determine the prevalence, risk factors and differences in outcomes of hyponatremia in TBM.

METHODS

This systematic review was registered in PROSPERO (CRD42018088089). A comprehensive electronic search was conducted through ten databases to find relevant articles.

RESULTS

A total of 42 studies were included, 24 case reports and 18 retrospective studies. The prevalence rate of hyponatremia among TBM patients was 52% and the rate of death among those patients was 29%. The meta-regression analysis revealed that there was no significant effect of sodium level on the death rate in TBM patients (P-value = 0.9). Additionally, there was no significant difference in sodium level based on sex, and etiologies of hyponatremia.

CONCLUSIONS

Hyponatremia is commonly present in patient with TBM, but it is not significantly correlated to the rate of death. However, it is necessary to treat this potentially life-threatening condition appropriately according to its etiology, further research is needed on its pathophysiology in TBM, its risk factors, and the most appropriate treatment.

LTA4H Prevalence and Mortality in Adult Zambians with Tuberculous Meningitis

We conducted a prospective cohort study to determine the prevalence of leukotriene A4 hydrolase (LTA4H) polymorphisms in Zambian adults with tuberculous meningitis (TBM) and its association with mortality. We completed genotype testing on 101 definite cases of TBM and 119 consecutive non-TBM controls. The distribution of genotypes among TBM patients was as follows: C/C (0.83), C/T (0.14), T/T (0.03). There was no significant difference in genotype distribution between TBM and non-TBM patients. We found no relationship between LTA4H polymorphism and survival. Prospective studies are needed to determine the benefit of adjuvant steroids in TBM based upon population LTA4H genotype. ANN NEUROL 2021.

Decrease in reproductive dysfunction using aflatoxin B1 exposure: a treatment with 3-indolepropionic acid in albino Wistar rat

We assessed the individual and combined consequence of 3-indolepropionic acid on aflatoxin B1-induced reproductive toxicity in rats. The experimental cohorts were dosed for four consecutive weeks with aflatoxin B1 (50 μg/kg), 3-indolepropionic acid (50 mg/kg), and both (aflatoxin B1: 50 μg/kg + 3-indolepropionic acid: 25 or 50 mg/kg), and the untreated control. Following sacrifice, biomarkers of testicular, epididymal and hypothalamic oxidative status, lipid peroxidation, reactive oxygen and nitrogen species, nitric oxide levels and myeloperoxidase activity were determined. Besides, tumour necrosis factor-alpha, Bcl-2 and Bax proteins were also assessed. Aflatoxin B1-induced testicular, epididymal and hypothalamic oxidative stress was significantly alleviated with 3-indolepropionic acid co-treatment. Also, increases in biomarkers of oxidative stress and reduced levels of antioxidants were abated significantly in rats co-treated with 3-indolepropionic acid. Aflatoxin B1-mediated increase in tumour necrosis factor-alpha, Bax, nitric oxide and myeloperoxidase activity in the examined organs was decreased significantly in aflatoxin B1 and 3-indolepropionic acid co-treated rats. Also, 3-indolepropionic acid dose dependently reduced Bcl-2 levels in the treated rats. The degree of aflatoxin B1-induced histopathological injuries was minimised in rats co-treated with 3-indolepropionic acid. Our results demonstrated that 3-indolepropionic acid protected experimental rats from aflatoxin B1-induced oxido-inflammatory stress and apoptotic response in the examined organs.

The use of thalidomide to treat children with tuberculosis meningitis: A review

Much of the morbidity and mortality caused by tuberculous meningitis (TBM) is mediated by a dysregulated immune response. Effective host-directed therapy is therefore critical to improve survival and clinical outcomes. Currently only one host-directed therapy (HDT), corticosteroids, is proven to improve mortality. However, there is no evidence that corticosteroids reduce morbidity and the mechanism of action for mortality reduction is uncertain. Further, it has no proven benefit in HIV co-infected individuals. One promising host-directed therapy approach is to restrict the immunopathology arising from tumour necrosis factor (TNF)-α excess is via TNF-α inhibitors. There are accumulating data on the role of thalidomide, anti-TNF-α monoclonal antibodies (infliximab, adalimumab) and the soluble TNF-α receptor (etanercept) in TBM treatment. Thalidomide was developed nearly seventy years ago and has been a highly controversial drug. Birth defects and toxic adverse effects have limited its use but an improved understanding of its immunological mechanism of action suggest that it may have a crucial role in regulating the destructive host response seen in inflammatory conditions such as TBM. Observational studies at our institution found low dosage adjunctive thalidomide safe in treating tuberculous mass lesions and blindness related to optochiasmatic arachnoiditis, with good clinical and radiological response. In this review, we discuss possible mechanisms of action for thalidomide, based on our clinico-radiologic experience and post-mortem histopathological work. We also propose a rationale for its use in the treatment of certain TBM-related complications.

The neuromicrobiology of Parkinson's disease: A unifying theory

Recent evidence confirms that PD is indeed a multifactorial disease with different aetiologies and prodromal symptomatology that likely depend on the initial trigger. New players with important roles as triggers, facilitators and aggravators of the PD neurodegenerative process have re-emerged in the last few years, the microbes. Having evolved in association with humans for ages, microbes and their products are now seen as fundamental regulators of human physiology with disturbances in their balance being increasingly accepted to have a relevant impact on the progression of disease in general and on PD in particular. In this review, we comprehensively address early studies that have directly or indirectly linked bacteria or other infectious agents to the onset and progression of PD, from the earliest suspects to the most recent culprits, the gut microbiota. The quest for effective treatments to arrest PD progression must inevitably address the different interactions between microbiota and human cells, and naturally consider the gut-brain axis. The comprehensive characterization of such mechanisms will help design innovative bacteriotherapeutic approaches to selectively shape the gut microbiota profile ultimately to halt PD progression. The present review describes our current understanding of the role of microorganisms and their endosymbiotic relatives, the mitochondria, in inducing, facilitating, or aggravating PD pathogenesis.

D-Dimer Combined With CRP Can Improve the Differential Value of Bacterial Meningitis and Tuberculous Meningitis

OBJECTIVE

To explore the diagnostic value of the coagulation marker D-dimer and its combination with the traditional marker C-reactive protein (CRP) in distinguishing bacterial meningitis (BM) from tuberculous meningitis (TM).

METHODS

We performed a retrospective study on specimens from 173 patients with meningitis who were hospitalized at the First Affiliated Hospital of Guangxi Medical University, Guangxi, China, from 2012 through 2020. The patient records were divided into the BM group and the TM group, and hematological parameters D-dimer and CRP were evaluated for the 2 groups.

RESULTS

The levels of D-dimer and CRP in the BM group were significantly higher than those levels in the TM group (P ˂.001 for each), and the sensitivity and specificity of the combined detection of the 2 markers was 86.3% to 100%; the area under the receiver operating characteristic (ROC) curve reached 0.983 (95% confidence interval [CI], 0.966-0.999).

CONCLUSION

D-dimer testing has high specificity in distinguishing between BM and TM; CRP testing also has high sensitivity. The combined diagnosis of the 2 biomarkers helps to distinguish TM from BM.

A Diagnostic Scoring System for Distinguishing between Tuberculous and Bacterial Meningitis Based on Clinical and Laboratory Findings

It is very difficult to diagnose and distinguish tuberculous meningitis, and the current laboratory methods are unsubstantial in developing countries. The study is aimed at creating a scoring system on the basis of basic laboratory and clinical achievements that could be used as diagnostic aid for tuberculous meningitis for Chinese patients. A retrospective study of cases was conducted for comparison between clinical characteristics and laboratory features of 241 patients on admission who conformed to inclusion criteria of tuberculous meningitis (n = 141) or bacterial meningitis (n = 100). Logistic regression was employed to establish a diagnostic formula to distinguish between tuberculous meningitis and bacterial meningitis. The receiver operating characteristic curve analysis was applied to determine the best diagnostic critical point of the diagnostic formula. It was found that five variables (disease course, white blood cell count, serum sodium, total white cell count of cerebrospinal fluid, and neutrophil proportion in cerebrospinal fluid) were independently associated with tuberculous meningitis. The 87% sensitivity and 94% specificity were included in the diagnostic scoring system derived from these variables. Especially in the case of limited microbial resources, doctors can use this diagnostic scoring system to distinguish tuberculous meningitis from bacterial meningitis.

Efficacy of Xpert MTB/RIF Ultra in diagnosing tuberculosis meningitis: A systematic review and meta-analysis

BACKGROUND

This study aimed to assess whether Xpert MTB/RIF Ultra (Xpert Ultra) can effectively diagnose tuberculosis meningitis (TBM) and to simultaneously compare its effectiveness with Xpert in diagnosing TBM in the same population.

METHODS

On August 12, 2020, Wanfang Database, China National Knowledge Infrastructure, Embase, Cochrane Library, and PubMed were searched for studies evaluating the diagnostic accuracy of Xpert Ultra for TBM. Then, we assessed the efficacy of Xpert Ultra against a composite reference standard and culture. If applicable, we also examined the diagnostic efficacy of Xpert in the same population. Heterogeneity was then explored by meta-regression, subgroup, and sensitivity analyses.

RESULTS

Six studies containing 601 specimens reported the diagnostic efficacy of Xpert Ultra for TBM, with a composite reference standard. No study had compared the efficacy between Xpert Ultra and culture. The pooled sensitivity of Xpert Ultra was 64% (95% confidence interval [CI]: 45-80), and the I2 value was 86% (95% CI: 76-96); its specificity for TBM was consistently 100%. In the same population, 5 studies compared the diagnostic efficacy between Xpert Ultra and Xpert for TBM. The pooled sensitivity of Xpert Ultra and Xpert was 68% (95% CI: 46-84; I2 = 87%) and 37% (95% CI: 25-50; I2 = 72%), respectively. The studies were significantly heterogeneous in terms of sensitivity but not heterogeneous in specificity.

CONCLUSIONS

Xpert Ultra was more sensitive than Xpert, but both were specific (100%). Therefore, Xpert Ultra had an excellent diagnostic efficacy for TBM, and it could be the preferred initial test for TBM.

Differences in cytokine and chemokine profiles in cerebrospinal fluid caused by the etiology of cryptococcal meningitis and tuberculous meningitis in HIV patients

The roles of cytokines and chemokines in HIV-associated cryptococcal meningitis (HCM) and HIV-associated tuberculous meningitis (HTBM) are debatable. In sum, 34 HIV-infected patients without meningitis, 44 HCM patients and 27 HTBM patients were enrolled for study. The concentrations of 22 cytokines/chemokines in cerebrospinal fluid (CSF) were assayed at admission. Principal component analysis (PCA), Pearson's and logistic regression analyses were used to assess the role of cytokines/chemokines in HCM and HTBM. We found the levels of T helper (Th)17, Th1 [interleukin (IL)-12p40, interferon (IFN)-γ, tumor necrosis factor (TNF)-α and TNF-β and Th2 (IL-2/4/5/6/10)] cytokines were elevated in patients with meningitis compared with those in HIV-infected patients without central nervous system (CNS) infection. Furthermore, the IL-1Ra, IL-12p40, IL-17α and monocyte chemotactic protein-1 (MCP-1) levels were higher in HCM patients, while the IFN-γ, regulated upon activation, normal T cell expressed and secreted (RANTES) and interferon-inducible protein-10 (IP)-10 levels were higher in HTBM patients. Elevated CSF concentrations of IL-17a, TNF-β, IL-5, IL-12p40 and IL-1Rα were closely related to meningitis, but elevated IP-10, MCP-1, RANTES and IFN-γ levels and CSF white blood cells (WBCs) were protective factors against HCM. Our study suggested that HIV-infected patients with low CSF WBCs have a high risk of HCM. Th1, Th2 and Th17 cytokines/chemokines mediate differences in the pathogenesis of HCM and TBM. Overexpressed proinflammatory MCP-1, RANTES, IFN-γ and IP-10 in CSF are protective factors against HCM but not HTBM.

Host Directed Therapies for Tuberculous Meningitis

A dysregulated host immune response significantly contributes to morbidity and mortality in tuberculous meningitis (TBM). Effective host directed therapies (HDTs) are critical to improve survival and clinical outcomes. Currently only one HDT, dexamethasone, is proven to improve mortality. However, there is no evidence dexamethasone reduces morbidity, how it reduces mortality is uncertain, and it has no proven benefit in HIV co-infected individuals. Further research on these aspects of its use, as well as alternative HDTs such as aspirin, thalidomide and other immunomodulatory drugs is needed. Based on new knowledge from pathogenesis studies, repurposed therapeutics which act upon small molecule drug targets may also have a role in TBM. Here we review existing literature investigating HDTs in TBM, and propose new rationale for the use of novel and repurposed drugs. We also discuss host variable responses and evidence to support a personalised approach to HDTs in TBM.

The role of optic nerve sheath diameter ultrasound in brain infection

Brain infections cause significant morbidity and mortality worldwide, especially in resource-limited settings with high HIV co-infection rates. Raised intracranial pressure [ICP] may complicate brain infection and worsen neurological injury, yet invasive ICP monitoring is often unavailable. Optic nerve sheath diameter [ONSD] ultrasound may allow detection of raised ICP at the bedside; however, pathology in brain infection is different to traumatic brain injury, in which most studies have been performed. The use of ONSD ultrasound has been described in tuberculous meningitis, cryptococcal meningitis and cerebral malaria; however correlation with invasive ICP measurement has not been performed. Normal optic nerve sheath values are not yet established for most populations, and thresholds for clinical intervention cannot be assumed to match those used in non-infective brain pathology. ONSD ultrasound may be suitable for use in resource-limited settings by clinicians with limited ultrasound training. Standardisation of scanning technique, consensus on normal ONSD values, and action on abnormal results, are areas for future research. This scoping review examines the role of ONSD ultrasound in brain infection. We discuss pathophysiology, and describe the rationale, practicalities, and challenges of utilising ONSD ultrasound for brain infection monitoring and management. We discuss the existing evidence base for this technique, and identify knowledge gaps and future research priorities.

Extrapulmonary Tuberculosis—An Update on the Diagnosis, Treatment and Drug Resistance

Pathogenic Mycobacterium tuberculosis complex organisms (MTBC) primarily cause pulmonary tuberculosis (PTB); however, MTBC are also capable of causing disease in extrapulmonary (EP) organs, which pose a significant threat to human health worldwide. Extrapulmonary tuberculosis (EPTB) accounts for about 20–30% of all active TB cases and affects mainly children and adults with compromised immune systems. EPTB can occur through hematogenous, lymphatic, or localized bacillary dissemination from a primary source, such as PTB, and affects the brain, eye, mouth, tongue, lymph nodes of neck, spine, bones, muscles, skin, pleura, pericardium, gastrointestinal, peritoneum, and the genitourinary system as primary and/or disseminated disease. EPTB diagnosis involves clinical, radiological, microbiological, histopathological, biochemical/immunological, and molecular methods. However, only culture and molecular techniques are considered confirmatory to differentiate MTBC from any non-tuberculous mycobacteria (NTM) species. While EPTB due to MTBC responds to first-line anti-TB drugs (ATD), drug susceptibility profiling is an essential criterion for addressing drug-resistant EPTB cases (DR-EPTB). Besides antibiotics, adjuvant therapy with corticosteroids has also been used to treat specific EPTB cases. Occasionally, surgical intervention is recommended, mainly when organ damage is debilitating to the patient. Recent epidemiological studies show a striking increase in DR-EPTB cases ranging from 10–15% across various reports. As a neglected disease, significant developments in rapid and accurate diagnosis and better therapeutic interventions are urgently needed to control the emerging EPTB situation globally. In this review, we discuss the recent advances in the clinical diagnosis, treatment, and drug resistance of EPTB.

The association between serum sodium level and tuberculous meningitis compared with viral and bacterial meningitis

We evaluated the association between hyponatremia and tuberculous meningitis (TBM) with the aim of providing additional information for differential diagnosis from other types of infectious meningitis, especially viral meningitis (VM). Cross-sectional and longitudinal data involving 5026 participants older than 18 years were analyzed in the total population and a propensity-matched population. The initial and lowest sodium levels and longitudinal changes in TBM, bacterial meningitis (BM), and VM patients were compared. Participants in the TBM group were enrolled when they were diagnosed as possible, probable, or definite TBM according to the Marais' criteria. The initial serum sodium level was significantly lower in TBM patients than in BM and VM patients (136.9 ± 5.9 vs. 138.3 ± 4.7 mmol/L, p < 0.001 for TBM vs. BM, and 139.0 ± 3.1, p < 0.001 for TBM vs. VM), and it decreased significantly more steeply to lower levels in both the TBM and BM patients compared with VM patients. The lowest serum sodium level was in the order of TBM < BM < VM patients, and the change was statistically significant in all subgroups (131.8 ± 6.4, 133.1 ± 5.1, 137.4 ± 3.7, respectively, p < 0.001). Participants with lower serum sodium level were more likely to have a diagnosis of TBM rather than VM, and this association was more pronounced for the lowest sodium level than the initial sodium level [OR 4.6 (95% CI 2.4-8.8, p < 0.001)]. These findings indicate that baseline and longitudinal evaluation of serum sodium level can provide information for differential diagnosis of TBM from BM or VM.

Feasibility and usefulness of tele-follow-up in the patients with tuberculous meningitis

Background

Tuberculous meningitis (TBM) is the most severe form of tuberculosis and these patients need close follow-up because of a high frequency of complications. The coronavirus disease 2019 pandemic and lockdown resulted in an interruption in physical follow-up. In this situation, tele-follow-up may be helpful. We report the feasibility and usefulness of a telephonic follow-up in patients with TBM.

Methods

Patients with TBM managed by us from January 2017 to March 2020 were included from the TBM registry. Their presenting symptoms, and clinical and investigation findings were noted. We contacted these patients telephonically and their clinical status was obtained using a questionnaire. Based on the telephonic information, outcomes were categorized as death, poor or good. Patients with the new medical problems were advised as to relevant investigations and the reports were obtained through WhatsApp for prescribing treatment.

Results

The telephone numbers of 103 of 144 (71.5%) patients were viable. Twenty-seven (26.2%) patients died, 15 (19.7%) had a poor outcome and 61 (80.2%) had a good outcome. Twenty-five (32.9%) patients had new medical problems: 18 TBM related and 7 TBM unrelated. The medical problems of 23 patients could be managed telephonically and only 3 (4%) patients needed a physical visit. Sixty-five (85.5%) patients happily answered the questionnaire and willing responders needed a treatment modification more frequently than the reluctant responders (p=0.008). Patients on active antitubercular treatment needed treatment modification more frequently (80% vs 21.3%).

Conclusions

Tele-follow-up is feasible in 96% of TBM patients and is beneficial, cost effective and overcomes the barrier of distance.

Ocular tuberculosis in a calf

Background

Bovine tuberculosis is a chronic inflammatory disease that causes granuloma formation mainly in retropharyngeal, tracheobronchial, mediastinal lymph nodes and lungs of bovines. The presence of these lesions in other tissues such as the eyeball is very rare and difficult to diagnose. This study describes macroscopic and microscopic pathological findings in a calf with ocular and meningeal tuberculosis.

Case presentation

March 2019, an eight-month-old Holstein Friesian calf was identified in a dairy farm located in central Mexico with a clinical cough, anorexia, incoordination, corneal opacity and vision loss. At necropsy, pneumonia, lymphadenitis, meningitis, and granulomatous iridocyclitis were observed. The histopathological examination revealed granulomatous lesions in lung tissue, lymph nodes, meninges and eyes with the presence of acid-fast bacilli associated with Mycobacterium spp.

Conclusion

To the best of our knowledge, this is the first report that describes macroscopic and microscopic pathological findings of ocular tuberculosis in cattle. This report highlights the importance of considering bovine tuberculosis in the differential diagnosis of corneal opacity and loss of vision in cattle.

Serum and cerebrospinal fluid host proteins indicate stroke in children with tuberculous meningitis

Introduction

Stroke is a common complication in children with tuberculous meningitis (TBM). Host proteins may give us insight into the mechanisms of stroke in TBM and serve as biomarkers for detection of stroke, however, they have not been widely explored. In this study, we compared the concentrations of cerebrospinal fluid (CSF) and serum proteins between children who had TBM-related stroke and children with TBM without stroke.

Methods

We collected CSF and serum from 47 children consecutively admitted to the Tygerberg Academic Hospital in Cape Town, South Africa between November 2016, and November 2017, on suspicion of having TBM. A multiplex platform was used to measure the concentrations of 69 host proteins in CSF and serum from all study participants.

Results

After classification of study participants, 23 (48.9%) out of the 47 study participants were diagnosed with TBM, of which 14 (60.9%) demonstrated radiological arterial ischemic infarction. The levels of lipocalin-2, sRAGE, IP-10/ CXCL10, sVCAM-1, MMP-1, and PDGF-AA in CSF samples and the levels of D-dimer, ADAMTS13, SAA, ferritin, MCP-1/ CCL2, GDF-15 and IL-13 in serum samples were statistically different between children who had TBM-related stroke and children with TBM without stroke. After correcting for multiple testing, only the levels of sVCAM-1, MMP-1, sRAGE, and IP-10/ CXCL10 in CSF were statistically different between the two groups. CSF and serum protein biosignatures indicated stroke in children diagnosed with TBM with up to 100% sensitivity and 88.9% specificity.

Conclusion

Serum and CSF proteins may serve as biomarkers for identifying individuals with stroke amongst children diagnosed with TBM at admission and may guide us to understand the biology of stroke in TBM. This was a pilot study, and thus further investigations in larger studies are needed.

Evaluation of the molecular bacterial load assay for detecting viable Mycobacterium tuberculosis in cerebrospinal fluid before and during tuberculous meningitis treatment

New tools to monitor treatment response and predict outcome from tuberculous meningitis (TBM) are urgently required. We retrospectively evaluated the 16S rRNA-based molecular bacterial load assay (MBLA) to quantify viable Mycobacterium tuberculosis in serial cerebrospinal fluid (CSF) from adults with TBM. 187 CSF samples were collected before and during the first two months of treatment from 99 adults TBM, comprising 56 definite, 43 probable or possible TBM, and 18 non-TBM and preserved at −80°C prior to MBLA. We compared MBLA against MGIT culture, GeneXpert MTB/RIF (Xpert) and Ziehl-Neelsen (ZN) smear. Before treatment, MBLA was positive in 34/99 (34.3%), significantly lower than MGIT 47/99 (47.5%), Xpert 51/99 (51.5%) and ZN smear 55/99 (55.5%). After one month of treatment, MBLA and MGIT were positive in 3/38 (7.9%) and 4/38 (10.5%), respectively, whereas Xpert and ZN smear remained positive in 19/38 (50.0%) and 18/38 (47.4%). In summary, MBLA was less likely to detect CSF bacteria before the start of treatment compared with MGIT culture, Xpert and ZN smear. MBLA and MGIT positivity fell during treatment because of detecting only viable bacteria, whereas Xpert and ZN smear remained positive for longer because of detecting both live and dead bacteria. Sample storage and processing may have reduced MBLA-detectable viable bacteria; and sampling earlier in treatment may yield more useful results. Prospective studies with CSF sampling after 1–2 weeks are warranted.

Thalidomide Use for Complicated Central Nervous System Tuberculosis in Children: Insights From an Observational Cohort

BACKGROUND

Much of the neurological sequelae of central nervous system (CNS) tuberculosis (TB) is due to an excessive cytokine-driven host-inflammatory response. Adjunctive corticosteroids, which reduce cytokine production and thus dampen the inflammation, improve overall survival but do not prevent morbidity. This has prompted investigation of more targeted immunomodulatory agents, including thalidomide.

METHODS

We describe a retrospective cohort of 38 children consecutively treated with adjunctive thalidomide for CNS TB-related complications over a 10-year period.

RESULTS

The most common presenting symptom was focal motor deficit (n = 16), followed by cranial nerve palsies and cerebellar dysfunction. Three of the 38 children presented with large dural-based lesions, manifesting as epilepsia partialis continua (EPC), 4 presented with blindness secondary to optochiasmatic arachnoiditis, and 2 children developed paraplegia due to spinal cord TB mass lesions. Duration of adjunctive thalidomide therapy (3-5 mg/kg/day) varied according to complication type. In children compromised by TB mass lesions, the median treatment duration was 3.9 months (interquartile range [IQR], 2.0-5.0 months), whereas in children with optic neuritis it was 2.0 months (IQR, 1.3-7.3 months) and in EPC it was 1.0 months (IQR, 1-2.5 months). Satisfactory clinical and radiological response was observed in 37 of the children. None of the children experienced rashes, hepatitis, or hematologic derangements or complained of leg cramps.

CONCLUSIONS

This study is the largest cohort of adult or pediatric patients treated with adjunctive thalidomide for CNS TB-related complications. The drug has proved to be safe and well tolerated and appears to be clinically efficacious. The potential role of thalidomide or analogues in the treatment of other tuberculous meningitis-related complications requires further exploration.

In Vitro and In Silico Evaluations of Anti-Mycobacterium tuberculosis Activity of Benzohydrazones Compounds

Tuberculosis is a disease caused by Mycobacterium tuberculosis, with high mortality rates and an extended treatment that causes severe adverse effects, besides the emergence of resistant bacteria. Therefore, the search for new compounds with anti-M. tuberculosis activity has considerably increased in recent years. In this context, benzohydrazones are significant compounds that have antifungal and antibacterial action. This study aimed at evaluating the in vitro activity of 18 benzohydrazones against M. tuberculosis. Compounds' cytotoxicity, inhibition of M. tuberculosis efflux pumps, and in silico absorption, distribution, metabolism, excretion, and toxicity (ADMET) assays were also performed. In general, the minimum inhibitory concentration values for the standard M. tuberculosis H₃₇Rv strain ranged from 7.8 to 250 μg/mL, and some compounds were not toxic to any of the cells tested (IC₅₀ ranged from 18.0 to 302.5 μg/mL). In addition, compounds (4) and (7) showed to be possible efflux pump inhibitors. In ADMET assays, all benzohydrazones had high gastrointestinal absorption. Most of the compounds were able to overcome the blood-brain barrier, and no compounds had irritant or tumorigenic effects. Compounds (1), (3), (9), (12), and (15) stood out for showing good activities, both in vitro and in silico assays.

Tuberculous meningitis: where to from here?

Tuberculous meningitis (TBM) is associated with significant mortality and morbidity yet is difficult to diagnose and treat. We reviewed original research published in the last 2 years, since 1 January 2018, which we considered to have a major impact in advancing diagnosis, treatment and understanding of the pathophysiology of TBM meningitis in children and adults.

The Treatment of Tuberculosis

Tuberculosis (TB) remains a leading cause of infectious death worldwide, and poverty is a major driver. Clinically, TB presents as "latent" TB and active TB disease, and the treatment for each is different. TB drugs can display "early bactericidal activity (EBA)" and / or "sterilizing activity" (clearing persisters). Isoniazid is excellent at the former, and rifampin is excellent at the latter. Pyrazinamide and ethambutol complete the first-line regimen for drug-susceptible TB, each playing a specific role. Drug-resistant TB is an increasing concern, being met, in part, with repurposed drugs (including moxifloxacin, levofloxacin, linezolid, clofazimine, and beta-lactams) and new drugs (including bedaquiline, pretomanid, and delamanid). One challenge is to select drugs without overlapping adverse drug reaction profiles. QTc interval prolongation is one such concern, but to date, it has been manageable. Drug penetration into organism sanctuaries, such as the central nervous system, bone, and pulmonary TB cavities remain important challenges. The pharmacodynamics of most TB drugs can be described by the area under the curve (AUC) divided by the minimal inhibitory concentration (MIC). The hollow fiber infection model (HFIM) and various animal models (especially mouse and macaque) allow for sophisticated pharmacokinetic/pharmacodynamic experiments. These experiments may hasten the selection of the most potent, shortest possible regimens to treat even extremely drug resistant TB. These findings can be translated to humans by optimizing drug exposure in each patient, using therapeutic drug monitoring and dose individualization.

Clinical, Imaging, and Laboratory Characteristics of Adult Mexican Patients with Tuberculous Meningitis: A Retrospective Cohort Study

Tuberculous Meningitis (TBM) is the most common form of central nervous system Tuberculosis (TB), accounting for 5–6% of extrapulmonary TB cases. Nowadays, TBM continues to be a major topic in public health because of its high prevalence worldwide. This retrospective study aimed to describe the clinical, laboratory, and imaging characteristics at admission; and in-hospital outcome of adult Mexican patients with TBM. We collected data from medical records of patients aged ≥18 years diagnosed with TBM according to the uniform case definition for clinical research who were treated at Tijuana General Hospital between January 2015 and March 2018 and compared them according to the subtype of diagnosis. We included 41 cases (26 males, median age 28 years, range 18–57 years), 13 (31.7%) patients were HIV positive, and 21 (51.2%) were illicit drug users. At admission, 7 (17.1%) patients were in stage I, 22 (53.6%) in stage II, and 12 (29.3%) in stage III. A definitive diagnosis was established in 23 (56.1%) patients, probable in 14 (34.1%), and possible in four (9.8%). Molecular testing was positive in 83% of the cases, yielding significantly higher positive results than other microbiological studies. There were eight (19.5%) deaths, without statistical difference between mortality and not having a definitive diagnosis (p = 0.109). We found that the baseline characteristics of our population were similar to those described by other authors worldwide. In this series, molecular testing showed to be very useful when used in the early stages, particularly in subjects with subacute onset of headache, fever, weight loss, and altered mental status.

Comparative analysis between tuberculous meningitis and other forms of extrapulmonary tuberculosis

Introduction

Tuberculosis is a multisystem disease that may affect any organ or tissue. Tuberculous meningitis (TBM) is the most severe form of tuberculosis and commonly affects the brain. We aimed to study the epidemiological, clinical, therapeutic and evolutionary features of TBM among adults and to compare them with other forms of extrapulmonary tuberculosis.

Methods

We conducted a retrospective study including all patients hospitalized for extrapulmonary tuberculosis in the infectious disease department in Sfax, Tunisia between 1993 and 2018. We specified the particularities of TBM cases, and we compared them with other extrapulmonary tuberculosis cases.

Results

We encountered 78 patients diagnosed with TBM, among 519 patients with extrapulmonary tuberculosis (15%). The median age was 36 years (23-50) years. There were 44 females (56.4%). In comparison with other forms of extrapulmonary tuberculosis, fever [odds ratio (OR)=4.4; p<0.001], asthenia (OR=3.4; p<0.001) and anorexia (OR=2.3; p=0.001) were significantly more frequent in TBM patients. Adverse effects of antitubercular therapy were more frequent among TBM patients (OR=3.1; p<0.001). The mean duration of antitubercular therapy was 15 (12-20) months. Recovery occurred in 66 cases (84.6%), complications in 44 cases (56.4%) and death in 7 cases (9%). Comparison of the disease evolution showed that complications (OR=7.4; p<0.001) and mortality rates (OR=10.7; p<0.001) were significantly more frequent in TBM patients, while recovery was significantly more frequent in other sites of extrapulmonary tuberculosis patients (OR=0.5; p=0.02).

Conclusions

In our country, TBM remains a disabling disease. Despite antitubercular therapy, the prognosis was more severe with the occurrence of not only complications but also a high mortality rate in comparison with other forms of extrapulmonary tuberculosis. When clinical and laboratory features suggest the diagnosis of TBM, clinicians should look for tuberculosis elsewhere in the body.

A pilot study of inflammatory mediators in brain extracellular fluid in paediatric TBM

Tuberculous meningitis (TBM) is the most fatal form of tuberculosis and frequently occurs in children. The inflammatory process initiates secondary brain injury processes that lead to death and disability. Much remains unknown about this cerebral inflammatory process, largely because of the difficulty in studying the brain. To date, studies have typically examined samples from sites distal to the site of disease, such as spinal cerebrospinal fluid (CSF) and blood. In this pilot study, we examined the feasibility of using direct brain microdialysis (MD) to detect inflammatory mediators in brain extracellular fluid (ECF) in TBM. MD was used to help guide neurocritical care in 7 comatose children with TBM by monitoring brain chemistry for up to 4 days. Remnant ECF fluid was stored for offline analysis. Samples of ventricular CSF, lumbar CSF and blood were collected at clinically indicated procedures for comparison. Inflammatory mediators were quantified using multiplex technology. All inflammatory markers, with the exception of interleukin (IL)-10 and IL-12p40, were detected in the ECF. Cytokine concentrations were generally lower in ECF than ventricular CSF in time-linked specimens. Individual cases showed ECF cytokine increases coinciding with marked increases in ECF glycerol or decreases in ECF glucose. Cytokine levels and glycerol were generally higher in patients with more severe disease. This is the first report of inflammatory marker analysis from samples derived directly from the brain and in high temporal resolution, demonstrating feasibility of cerebral MD to explore disease progression and possibly therapy response in TBM.

Elevated cerebrospinal fluid cytokine levels in tuberculous meningitis predict survival in response to dexamethasone

Adjunctive treatment with antiinflammatory corticosteroids like dexamethasone increases survival in tuberculosis meningitis. Dexamethasone responsiveness associates with a C/T variant in Leukotriene A4 Hydrolase (LTA4H), which regulates expression of the proinflammatory mediator leukotriene B4 (LTB4). TT homozygotes, with increased expression of LTA4H, have the highest survival when treated with dexamethasone and the lowest survival without. While the T allele is present in only a minority of the world's population, corticosteroids confer modest survival benefit worldwide. Using Bayesian methods, we examined how pretreatment levels of cerebrospinal fluid proinflammatory cytokines affect survival in dexamethasone-treated tuberculous meningitis. LTA4H TT homozygosity was associated with global cytokine increases, including tumor necrosis factor. Association between higher cytokine levels and survival extended to non-TT patients, suggesting that other genetic variants may also induce dexamethasone-responsive pathological inflammation. These findings warrant studies that tailor dexamethasone therapy to pretreatment cerebrospinal fluid cytokine concentrations, while searching for additional genetic loci shaping the inflammatory milieu.