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Current Opinion in Infectious Diseases Jun 2020Central nervous system (CNS) infections associated with HIV remain significant contributors to morbidity and mortality, particularly among people living with HIV (PLWH)... (Review)
Review
PURPOSE OF REVIEW
Central nervous system (CNS) infections associated with HIV remain significant contributors to morbidity and mortality, particularly among people living with HIV (PLWH) in resource-limited settings worldwide. In this review, we discuss several recent important scientific discoveries in the prevention, diagnosis, and management around two of the major causes of CNS opportunistic infections-tuberculous meningitis (TBM) and cryptococcal meningitis including immune reconstitution syndrome (IRIS) associated with cryptococcal meningitis. We also discuss the CNS as a possible viral reservoir, highlighting Cerebrospinal fluid viral escape.
RECENT FINDINGS
CNS infections in HIV-positive people in sub-Saharan Africa contribute to 15-25% of AIDS-related deaths. Morbidity and mortality in those is associated with delays in HIV diagnosis, lack of availability for antimicrobial treatment, and risk of CNS IRIS. The CNS may serve as a reservoir for replication, though it is unclear whether this can impact peripheral immunosuppression.
SUMMARY
Significant diagnostic and treatment advances for TBM and cryptococcal meningitis have yet to impact overall morbidity and mortality according to recent data. Lack of early diagnosis and treatment initiation, and also maintenance on combined antiretroviral treatment are the main drivers of the ongoing burden of CNS opportunistic infections. The CNS as a viral reservoir has major potential implications for HIV eradication strategies, and also control of CNS opportunistic infections.
Topics: Central Nervous System Infections; HIV Infections; Humans; Immune Reconstitution Inflammatory Syndrome; Meningitis, Cryptococcal; Opportunistic Infections; Tuberculosis, Meningeal; Viruses
PubMed: 32332225
DOI: 10.1097/QCO.0000000000000652 -
Clinica Chimica Acta; International... Aug 2023Meningitis is defined as the inflammation of the meninges that is most often caused by various bacterial and viral pathogens, and is associated with high rates of... (Review)
Review
Meningitis is defined as the inflammation of the meninges that is most often caused by various bacterial and viral pathogens, and is associated with high rates of mortality and morbidity. Early detection of bacterial meningitis is essential to appropriate antibiotic therapy. Alterations in immunologic biomarkers levels have been considered the diagnostic approach in medical laboratories for the identifying of infections. The early increasing immunologic mediators such as cytokines and acute phase proteins (APPs) during bacterial meningitis have made they significant indicators for laboratory diagnosis. Immunology biomarkers showed wide variable sensitivity and specificity values that influenced by different reference values, selected a certain cutoff point, methods of detection, patient characterization and inclusion criteria, as well as etiology of meningitis and time of CSF or blood specimens' collection. This study provides an overview of different immunologic biomarkers as diagnostic markers for the identification of bacterial meningitis and their efficiencies in the differentiating of bacterial from viral meningitis.
Topics: Humans; Meningitis, Bacterial; Biomarkers; Meningitis, Viral; Inflammation; Cytokines; Bacteria
PubMed: 37419301
DOI: 10.1016/j.cca.2023.117470 -
World Neurosurgery May 2020Rheumatoid meningitis is a rare manifestation of autoimmune rheumatoid arthritis.
BACKGROUND
Rheumatoid meningitis is a rare manifestation of autoimmune rheumatoid arthritis.
CASE DESCRIPTION
A 70-year-old man with rheumatoid arthritis had presented with speech difficulties and limb weakness. Magnetic resonance imaging of his brain demonstrated diffuse meningeal enhancement. A biopsy confirmed the presence of rheumatoid meningitis.
CONCLUSION
In the present report, we have discussed the diagnostic and therapeutic approach to rheumatoid meningitis.
Topics: Aged; Arthritis, Rheumatoid; Biopsy; Brain; Humans; Magnetic Resonance Imaging; Male; Meningitis
PubMed: 32035199
DOI: 10.1016/j.wneu.2020.01.220 -
Cell Stem Cell Nov 2023The meninges lie in the interface between the skull and brain, harboring lymphatic vasculature and skull progenitor cells (SPCs). How the skull and brain communicate...
The meninges lie in the interface between the skull and brain, harboring lymphatic vasculature and skull progenitor cells (SPCs). How the skull and brain communicate remains largely unknown. We found that impaired meningeal lymphatics and brain perfusion drive neurocognitive defects in Twist1 mice, an animal model of craniosynostosis recapitulating human Saethre-Chotzen syndrome. Loss of SPCs leads to skull deformities and elevated intracranial pressure (ICP), whereas transplanting SPCs back into mutant mice mitigates lymphatic and brain defects through two mechanisms: (1) decreasing elevated ICP by skull correction and (2) promoting the growth and migration of lymphatic endothelial cells (LECs) via SPC-secreted vascular endothelial growth factor-C (VEGF-C). Treating Twist1 mice with VEGF-C promotes meningeal lymphatic growth and rescues defects in ICP, brain perfusion, and neurocognitive functions. Thus, the skull functionally integrates with the brain via meningeal lymphatics, which is impaired in craniosynostosis and can be restored by SPC-driven lymphatic activation via VEGF-C.
Topics: Mice; Humans; Animals; Vascular Endothelial Growth Factor C; Endothelial Cells; Skull; Meninges; Craniosynostoses; Stem Cells
PubMed: 37863055
DOI: 10.1016/j.stem.2023.09.012 -
Acta Neurochirurgica Jan 2021
Topics: Arachnoid; Arachnoiditis; Arnold-Chiari Malformation; Humans; Syringomyelia
PubMed: 32948891
DOI: 10.1007/s00701-020-04584-3 -
The Neuroscientist : a Review Journal... Oct 2021Emerging evidence highlights the several roles that meninges play in relevant brain functions as they are a protective membrane for the brain, produce and release... (Review)
Review
Emerging evidence highlights the several roles that meninges play in relevant brain functions as they are a protective membrane for the brain, produce and release several trophic factors important for neural cell migration and survival, control cerebrospinal fluid dynamics, and embrace numerous immune interactions affecting neural parenchymal functions. Furthermore, different groups have identified subsets of neural progenitors residing in the meninges during development and in the adulthood in different mammalian species, including humans. Interestingly, these immature neural cells are able to migrate from the meninges to the neural parenchyma and differentiate into functional cortical neurons or oligodendrocytes. Immature neural cells residing in the meninges promptly react to brain disease. Injury-induced expansion and migration of meningeal neural progenitors have been observed following experimental demyelination, traumatic spinal cord and brain injury, amygdala lesion, stroke, and progressive ataxia. In this review, we summarize data on the function of meninges as stem cell niche and on the presence of immature neural cells in the meninges, and discuss their roles in brain health and disease. Furthermore, we consider the potential exploitation of meningeal neural progenitors for the regenerative medicine to treat neurological disorders.
Topics: Adult; Animals; Brain; Cell Differentiation; Humans; Meninges; Neural Stem Cells; Neurogenesis
PubMed: 32935634
DOI: 10.1177/1073858420954826 -
FASEB Journal : Official Publication of... May 2022The lymphatic vasculature is a unidirectional network of lymphatic endothelial cells, whose main role is to maintain fluid homeostasis along with the absorption of... (Review)
Review
The lymphatic vasculature is a unidirectional network of lymphatic endothelial cells, whose main role is to maintain fluid homeostasis along with the absorption of dietary fat in the gastrointestinal organs and management and coordination of immune cell trafficking into lymph nodes during homeostasis and under inflammatory conditions. In homeostatic conditions, immune cells, such as dendritic cells, macrophages, or T cells can enter into the lymphatic vasculature and move easily through the lymph reaching secondary lymph nodes where immune cell activation or peripheral tolerance can be modulated. However, under inflammatory conditions such as pathogen infection, increased permeabilization of lymphatic vessels allows faster immune cell migration into inflamed tissues following a chemokine gradient, facilitating pathogen clearance and the resolution of inflammation. Interestingly, since the re-discovery of lymphatic vasculature in the central nervous system, known as the meningeal lymphatic vasculature, the role of these lymphatics as a key player in several neurological disorders has been described, with emphasis on the neurodegenerative process. Alternatively, less has been discussed about meningeal lymphatics and its role in neuroinflammation. In this review, we discuss current knowledge about the anatomy and function of the meningeal lymphatic vasculature and specifically analyze its contribution to different neuroinflammatory processes, highlighting the potential therapeutic target of meningeal lymphatic vasculature in these pathological conditions.
Topics: Endothelial Cells; Humans; Lymphatic System; Lymphatic Vessels; Meninges; Neuroinflammatory Diseases
PubMed: 35344212
DOI: 10.1096/fj.202101574RR -
Current Opinion in Neurobiology Apr 2023The spatial and temporal development of the brain, overlying meninges (fibroblasts, vasculature and immune cells) and calvarium are highly coordinated. In particular,... (Review)
Review
The spatial and temporal development of the brain, overlying meninges (fibroblasts, vasculature and immune cells) and calvarium are highly coordinated. In particular, the timing of meningeal fibroblasts into molecularly distinct pia, arachnoid and dura subtypes coincides with key developmental events in the brain and calvarium. Further, the meninges are positioned to influence development of adjacent structures and do so via depositing basement membrane and producing molecular cues to regulate brain and calvarial development. Here, we review the current knowledge of how meninges development aligns with events in the brain and calvarium and meningeal fibroblast "crosstalk" with these structures. We summarize outstanding questions and how the use of non-mammalian models to study the meninges will substantially advance the field of meninges biology.
Topics: Meninges; Dura Mater; Arachnoid; Brain
PubMed: 36773497
DOI: 10.1016/j.conb.2023.102676 -
Journal of the Neurological Sciences Apr 2020Central nervous system (CNS) metastasis from systemic cancers can involve the brain parenchyma, leptomeninges (pia, subarachnoid space and arachnoid mater), and dura.... (Review)
Review
Central nervous system (CNS) metastasis from systemic cancers can involve the brain parenchyma, leptomeninges (pia, subarachnoid space and arachnoid mater), and dura. Leptomeningeal metastases (LM), also known by different terms including neoplastic meningitis and carcinomatous meningitis, occur in both solid tumors and hematologic malignancies. This review will focus exclusively on LM arising from solid tumors with a goal of providing the reader an understanding of the epidemiology, pathophysiology, clinical presentation, prognostication, current management and future directions.
Topics: Arachnoid; Dura Mater; Humans; Meningeal Carcinomatosis; Meningeal Neoplasms; Meninges; Meningitis, Bacterial; Neoplasms
PubMed: 32007755
DOI: 10.1016/j.jns.2020.116706 -
European Journal of Immunology Sep 2023In the past 10 years, important discoveries have been made in the field of neuroimmunology, especially regarding brain borders. Indeed, meninges are protective envelopes... (Review)
Review
In the past 10 years, important discoveries have been made in the field of neuroimmunology, especially regarding brain borders. Indeed, meninges are protective envelopes surrounding the CNS and are currently in the spotlight, with multiple studies showing their involvement in brain infection and cognitive disorders. In this review, we describe the meningeal layers and their protective role in the CNS against bacterial, viral, fungal, and parasitic infections, by immune and nonimmune cells. Moreover, we discuss the neurological and cognitive consequences resulting from meningeal infections in neonates (e.g. infection with group B Streptococcus, cytomegalovirus, …) or adults (e.g. infection with Trypanosoma brucei, Streptococcus pneumoniae, …). We hope that this review will bring to light an integrated view of meningeal immune regulations during CNS infections and their neurological consequences.
Topics: Adult; Infant, Newborn; Humans; Meninges; Brain; Central Nervous System Infections; Streptococcus pneumoniae
PubMed: 37402972
DOI: 10.1002/eji.202250267