•Chronic neurological disease and acute abnormalities are present in COVID-19 brain autopsies.•Acute hypoxic-injury, hemorrhage, and minimal inflammation are frequently observed.•Low levels of viral ...SARS-CoV-2 RNA are present; cellular source remains unknown.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative agent of coronavirus disease 2019 (COVID-19) for which there have been over 50 million confirmed cases and 1.2 million deaths globally. While many SARS-CoV-2 infected individuals are asymptomatic or experience respiratory symptoms, extrapulmonary manifestations, including neurological symptoms and conditions, are increasingly recognized. There remains no clear understanding of the mechanisms that underlie neurological symptoms in COVID-19 and whether SARS-CoV-2 has the potential for neuroinvasion in humans. In this minireview, we discuss what is known from human autopsies in fatal COVID-19, including highlighting studies that investigate for the presence of SARS-CoV-2 in brain and olfactory tissue, and summarize the neuropathological consequences of infection. Incorporating microscopic and molecular findings from brain tissue into what we know about clinical disease will inform best practice management guidance and direct research priorities as it relates to neurological morbidity from COVID-19.
Objective
The purpose of this study was to describe cerebrovascular, neuropathic, and autonomic features of post‐acute sequelae of coronavirus disease 2019 ((COVID‐19) PASC).
Methods
This ...retrospective study evaluated consecutive patients with chronic fatigue, brain fog, and orthostatic intolerance consistent with PASC. Controls included patients with postural tachycardia syndrome (POTS) and healthy participants. Analyzed data included surveys and autonomic (Valsalva maneuver, deep breathing, sudomotor, and tilt tests), cerebrovascular (cerebral blood flow velocity CBFv monitoring in middle cerebral artery), respiratory (capnography monitoring), and neuropathic (skin biopsies for assessment of small fiber neuropathy) testing and inflammatory/autoimmune markers.
Results
Nine patients with PASC were evaluated 0.8 ± 0.3 years after a mild COVID‐19 infection, and were treated as home observations. Autonomic, pain, brain fog, fatigue, and dyspnea surveys were abnormal in PASC and POTS (n = 10), compared with controls (n = 15). Tilt table test reproduced the majority of PASC symptoms. Orthostatic CBFv declined in PASC (−20.0 ± 13.4%) and POTS (−20.3 ± 15.1%), compared with controls (−3.0 ± 7.5%, p = 0.001) and was independent of end‐tidal carbon dioxide in PASC, but caused by hyperventilation in POTS. Reduced orthostatic CBFv in PASC included both subjects without (n = 6) and with (n = 3) orthostatic tachycardia. Dysautonomia was frequent (100% in both PASC and POTS) but was milder in PASC (p = 0.002). PASC and POTS cohorts diverged in frequency of small fiber neuropathy (89% vs 60%) but not in inflammatory markers (67% vs 70%). Supine and orthostatic hypocapnia was observed in PASC.
Interpretation
PASC following mild COVID‐19 infection is associated with multisystem involvement including: (1) cerebrovascular dysregulation with persistent cerebral arteriolar vasoconstriction; (2) small fiber neuropathy and related dysautonomia; (3) respiratory dysregulation; and (4) chronic inflammation. ANN NEUROL 2022;91:367–379
Neuropathological Features of Covid-19 Solomon, Isaac H; Normandin, Erica; Bhattacharyya, Shamik ...
The New England journal of medicine,
09/2020, Volume:
383, Issue:
10
Journal Article
Objective and early identification of hospitalized patients, and particularly those with novel coronavirus disease 2019 (COVID-19), who may require mechanical ventilation (MV) may aid in delivering ...timely treatment.
Can a transparent deep learning (DL) model predict the need for MV in hospitalized patients and those with COVID-19 up to 24 h in advance?
We trained and externally validated a transparent DL algorithm to predict the future need for MV in hospitalized patients, including those with COVID-19, using commonly available data in electronic health records. Additionally, commonly used clinical criteria (heart rate, oxygen saturation, respiratory rate, Fio2, and pH) were used to assess future need for MV. Performance of the algorithm was evaluated using the area under receiver operating characteristic curve (AUC), sensitivity, specificity, and positive predictive value.
We obtained data from more than 30,000 ICU patients (including more than 700 patients with COVID-19) from two academic medical centers. The performance of the model with a 24-h prediction horizon at the development and validation sites was comparable (AUC, 0.895 vs 0.882, respectively), providing significant improvement over traditional clinical criteria (P < .001). Prospective validation of the algorithm among patients with COVID-19 yielded AUCs in the range of 0.918 to 0.943.
A transparent deep learning algorithm improves on traditional clinical criteria to predict the need for MV in hospitalized patients, including in those with COVID-19. Such an algorithm may help clinicians to optimize timing of tracheal intubation, to allocate resources and staff better, and to improve patient care.
The relationship of cerebrospinal fluid (CSF) extracellular vesicles to neurocognitive impairment (NCI) in HIV-infected individuals is unclear. Here, we characterize CSF extracellular vesicles and ...their association with central nervous system (CNS) injury related biomarkers neurofilament light (NFL), S100B, neopterin and NCI in HIV-positive individuals on combination antiretroviral therapy (cART).
A cross-sectional and longitudinal study of CSF samples from HIV-positive individuals on cART.
NFL, S100B and neopterin were measured by ELISA in 190 CSF samples from 112 individuals (67 HIV-positive and 45 HIV-negative). CSF extracellular vesicles were isolated and characterized by electron microscopy, nanoparticle tracking analysis, immunoblotting for exosome markers (CD9, CD63, CD81, FLOT-1) and ELISA for HLA-DR.
HIV-positive individuals had median age 52 years, 67% with suppressed plasma viral load (< 50 copies/ml), median CD4 nadir 66 cells/μl and CD4 cell count 313 cells/μl. CSF NFL, S100B and neopterin levels were higher in HIV-positive vs. HIV-negative individuals, and nonsuppressed vs. suppressed HIV-positive individuals. Although CSF NFL and S100B levels were higher in NCI vs. unimpaired HIV-positive individuals (P < 0.05), only NFL was associated with NCI in adjusted models (P < 0.05). CSF extracellular vesicles were increased in HIV-positive vs. HIV-negative individuals, and NCI vs. unimpaired HIV-positive individuals (P < 0.05), and correlated positively with NFL (P < 0.001). HLA-DR was enriched in CSF extracellular vesicles from HIV-positive individuals with NCI (P < 0.05), suggesting that myeloid cells are a potential source of CSF extracellular vesicles during HIV infection.
Increased CSF extracellular vesicles correlate with neuronal injury biomarker NFL in cART-treated HIV-positive individuals with neurocognitive impairment, suggesting potential applications as novel biomarkers of CNS injury.
SARS-CoV-2 distribution and circulation dynamics are not well understood due to challenges in assessing genomic data from tissue samples. We develop experimental and computational workflows for ...high-depth viral sequencing and high-resolution genomic analyses from formalin-fixed, paraffin-embedded tissues and apply them to 120 specimens from six subjects with fatal COVID-19. To varying degrees, viral RNA is present in extrapulmonary tissues from all subjects. The majority of the 180 viral variants identified within subjects are unique to individual tissue samples. We find more high-frequency (>10%) minor variants in subjects with a longer disease course, with one subject harboring ten such variants, exclusively in extrapulmonary tissues. One tissue-specific high-frequency variant was a nonsynonymous mutation in the furin-cleavage site of the spike protein. Our findings suggest adaptation and/or compartmentalized infection, illuminating the basis of extrapulmonary COVID-19 symptoms and potential for viral reservoirs, and have broad utility for investigating human pathogens.
Protease inhibitors were independent predictors of cerebrospinal fluid (CSF) escape in antiretroviral therapy (ART)-experienced human immunodeficiency virus-infected adults. M184V/I combined with ...thymidine analog mutations were more frequent in adults with CSF escape compared to no escape. These findings suggest optimizing ART may reduce likelihood of CSF escape.
Abstract
Background
Cerebrospinal fluid (CSF) viral escape occurs in 4%-20% of human immunodeficiency virus (HIV)-infected adults, yet the impact of antiretroviral therapy (ART) on CSF escape is unclear.
Methods
A prospective study of 1063 participants with baseline plasma viral load (VL) ≤400 copies/mL between 2005 and 2016. The odds ratio (OR) for ART regimens (protease inhibitor with nucleoside reverse transcriptase inhibitor PI + NRTI vs other ART) and CSF escape was estimated using mixed-effects models.
Results
Baseline mean age was 46 years, median plasma VL, and CD4 count were 50 copies/mL, and 424 cells/μL, respectively. During median follow-up of 4.4 years, CSF escape occurred in 77 participants (7.2%). PI + NRTI use was an independent predictor of CSF escape (OR, 3.1; 95% confidence interval, 1.8-5.0) in adjusted analyses and models restricted to plasma VL ≤50 copies/mL (P < .001). Regimens that contained atazanavir (ATV) were a stronger predictor of CSF viral escape than non-ATV PI + NRTI regimens. Plasma and CSF M184V/I combined with thymidine-analog mutations were more frequent in CSF escape vs no escape (23% vs 2.3%). Genotypic susceptibility score-adjusted central nervous system (CNS) penetration-effectiveness (CPE) values were calculated for CSF escape with M184V/I mutations (n = 34). Adjusted CPE values were low (<5) for CSF in 27 (79%), indicating suboptimal CNS drug availability.
Conclusions
PI + NRTI regimens are independent predictors of CSF escape in HIV-infected adults. Reduced CNS ART bioavailability may predispose to CSF escape in patients with M184V/I mutations.
Meningitis and encephalitis are leading causes of central nervous system (CNS) disease and often result in severe neurological compromise or death. Traditional diagnostic workflows largely rely on ...pathogen-specific tests, sometimes over days to weeks, whereas metagenomic next-generation sequencing (mNGS) profiles all nucleic acid in a sample. In this single-center, prospective study, 68 hospitalized patients with known (
= 44) or suspected (
= 24) CNS infections underwent mNGS from RNA and DNA to identify potential pathogens and also targeted sequencing of viruses using hybrid capture. Using a computational metagenomic classification pipeline based on KrakenUniq and BLAST, we detected pathogen nucleic acid in cerebrospinal fluid (CSF) from 22 subjects, 3 of whom had no clinical diagnosis by routine workup. Among subjects diagnosed with infection by serology and/or peripheral samples, we demonstrated the utility of mNGS to detect pathogen nucleic acid in CSF, importantly for the Ixodes scapularis tick-borne pathogens Powassan virus, Borrelia burgdorferi, and Anaplasma phagocytophilum. We also evaluated two methods to enhance the detection of viral nucleic acid, hybrid capture and methylated DNA depletion. Hybrid capture nearly universally increased viral read recovery. Although results for methylated DNA depletion were mixed, it allowed the detection of varicella-zoster virus DNA in two samples that were negative by standard mNGS. Overall, mNGS is a promising approach that can test for multiple pathogens simultaneously, with efficacy similar to that of pathogen-specific tests, and can uncover geographically relevant infectious CNS disease, such as tick-borne infections in New England. With further laboratory and computational enhancements, mNGS may become a mainstay of workup for encephalitis and meningitis.
Meningitis and encephalitis are leading global causes of central nervous system (CNS) disability and mortality. Current diagnostic workflows remain inefficient, requiring costly pathogen-specific assays and sometimes invasive surgical procedures. Despite intensive diagnostic efforts, 40 to 60% of people with meningitis or encephalitis have no clear cause of CNS disease identified. As diagnostic uncertainty often leads to costly inappropriate therapies, the need for novel pathogen detection methods is paramount. Metagenomic next-generation sequencing (mNGS) offers the unique opportunity to circumvent these challenges using unbiased laboratory and computational methods. Here, we performed comprehensive mNGS from 68 prospectively enrolled patients with known (
= 44) or suspected (
= 24) CNS viral infection from a single center in New England and evaluated enhanced methods to improve the detection of CNS pathogens, including those not traditionally identified in the CNS by nucleic acid detection. Overall, our work helps elucidate how mNGS can become integrated into the diagnostic toolkit for CNS infections.
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