Category: Overlapping Illnesses

NETosis induction reflects COVID-19 severity and Long COVID: insights from a two-center patient cohort study in Israel

Abstract:

Background: COVID-19 severity and its late complications continue to be poorly understood. Neutrophil extracellular traps (NETs) form in acute COVID-19, likely contributing to morbidity and mortality. This study evaluated immunothrombosis markers in a comprehensive cohort of acute and recovered COVID-19 patients, including the association of NETs with LongCOVID.

Methods: One-hundred-seventy-seven patients were recruited from clinical cohorts at two Israeli centers: acute COVID-19 (mild/moderate, severe/critical), convalescent COVID-19 (recovered and Long COVID), along with 54 non-COVID controls. Plasma was examined for markers of platelet activation, coagulation, and NETs. Ex vivo NETosis induction capability was evaluated after neutrophil incubation with patient plasma.

Results: Soluble P-selectin, Factor VIII, von Willebrand factor, and platelet factor 4 were significantly elevated in COVID-19 patients versus controls. Myeloperoxidase (MPO)-DNA complex levels were increased only in severe COVID-19 and did not differentiate between COVID-19 severities or correlate with thrombotic markers. NETosis induction levels strongly correlated with illness severity/duration, platelet activation markers, and coagulation factors, and were significantly reduced upon dexamethasone treatment and recovery. Long COVID patients maintained higher NETosis induction, but not NET fragments, compared to recovered convalescent patients.

Conclusions: Increased NETosis induction can be detected in Long COVID patients. NETosis induction appears to be a more sensitive NET measurement than MPO-DNA levels in COVID-19, differentiating between disease severity and Long COVID patients. Ongoing NETosis induction capability in Long COVID may provide insights into pathogenesis and serve as a surrogate marker for persistent pathology. This study emphasizes the need to explore neutrophil-targeted therapies in acute and chronic COVID-19.

Source: Krinsky N, Sizikov S, Nissim S, Dror A, Sas A, Prinz H, Pri-Or E, Perek S, Raz-Pasteur A, Lejbkowicz I, Cohen-Matsliah SI, Almog R, Chen N, Kurd R, Jarjou’i A, Rokach A, Ben-Chetrit E, Schroeder A, Caulin AF, Yost CC, Schiffman JD, Goldfeder M, Martinod K. NETosis induction reflects COVID-19 severity and Long COVID: insights from a two-center patient cohort study in Israel. J Thromb Haemost. 2023 Apr 11:S1538-7836(23)00274-X. doi: 10.1016/j.jtha.2023.02.033. Epub ahead of print. PMID: 37054916; PMCID: PMC10088279. https://www.jthjournal.org/article/S1538-7836(23)00274-X/fulltext (Full text available as PDF file)

Efficacy and tolerability of an endogenous metabolic modulator (AXA1125) in fatigue-predominant long COVID: a single-centre, double-blind, randomised controlled phase 2a pilot study

Summary:

Background: ‘Long COVID’ describes persistent symptoms, commonly fatigue, lasting beyond 12 weeks following SARS-CoV-2 infection. Potential causes include reduced mitochondrial function and cellular bioenergetics. AXA1125 has previously increased β-oxidation and improved bioenergetics in preclinical models along with certain clinical conditions, and therefore may reduce fatigue associated with Long COVID. We aimed to assess the efficacy, safety and tolerability of AXA1125 in Long COVID.

Methods: Patients with fatigue dominant Long COVID were recruited in this single-centre, double-blind, randomised controlled phase 2a pilot study completed in the UK. Patients were randomly assigned (1:1) using an Interactive Response Technology to receive either AXA1125 or matching placebo in a clinical based setting. Each dose (33.9 g) of AXA1125 or placebo was administered orally in a liquid suspension twice daily for four weeks with a two week follow-up period. The primary endpoint was the mean change from baseline to day 28 in the phosphocreatine (PCr) recovery rate following moderate exercise, assessed by 31P-magnetic resonance spectroscopy (MRS). All patients were included in the intention to treat analysis. This trial was registered at ClinicalTrials.gov, NCT05152849.

Findings: Between December 15th 2021, and May 23th 2022, 60 participants were screened and 41 participants were randomised and included in the final analysis. Changes in skeletal muscle phosphocreatine recovery time constant (τPCr) and 6-min walk test (6MWT) did not significantly differ between treatment (n = 21) and placebo group (n = 20). However, treatment with AXA1125 was associated with significantly reduced day 28 Chalder Fatigue Questionnaire [CFQ-11] fatigue score when compared with placebo (least squares mean difference [LSMD] −4.30, 95% confidence interval (95% CI) −7.14, −1.47; P = 0.0039). Eleven (52.4%, AXA1125) and four (20.0%, placebo) patients reported treatment-emergent adverse events; none were serious, or led to treatment discontinuation.

Interpretation: Although treatment with AXA1125 did not improve the primary endpoint (τPCr-measure of mitochondrial respiration), when compared to placebo, there was a significant improvement in fatigue-based symptoms among patients living with Long COVID following a four week treatment period. Further multicentre studies are needed to validate our findings in a larger cohort of patients with fatigue-dominant Long COVID.

Source: Lucy E.M. Finnigan, Mark Philip Cassar, Margaret James Koziel, Joel Pradines, Hanan Lamlum, Karim Azer, et al. Efficacy and tolerability of an endogenous metabolic modulator (AXA1125) in fatigue-predominant long COVID: a single-centre, double-blind, randomised controlled phase 2a pilot study. The Lancet, Published: April 14, 2023 DOI: https://doi.org/10.1016/j.eclinm.2023.101946 (Full text)

Exercise Intolerance Associated with Impaired Oxygen Extraction in Patients with Long COVID

Abstract:

Objective: Chronic mental and physical fatigue and post-exertional malaise are the more debilitating symptoms of long COVID-19. The study objective was to explore factors contributing to exercise intolerance in long COVID-19 to guide development of new therapies. Exercise capacity data of patients referred for a cardiopulmonary exercise test (CPET) and included in a COVID-19 Survivorship Registry at one urban health center were retrospectively analyzed.

Results: Most subjects did not meet normative criteria for a maximal test, consistent with suboptimal effort and early exercise termination. Mean O2 pulse peak % predicted (of 79 ± 12.9) was reduced, supporting impaired energy metabolism as a mechanism of exercise intolerance in long COVID, n=59. We further identified blunted rise in heart rate peak during maximal CPET. Our preliminary analyses support therapies that optimize bioenergetics and improve oxygen utilization for treating long COVID-19.

Source: Norweg A, Yao L, Barbuto S, Nordvig AS, Tarpey T, Collins E, Whiteson J, Sweeney G, Haas F, Leddy J. Exercise Intolerance Associated with Impaired Oxygen Extraction in Patients with Long COVID. Respir Physiol Neurobiol. 2023 Apr 17;313:104062. doi: 10.1016/j.resp.2023.104062. Epub ahead of print. PMID: 37076024; PMCID: PMC10108551. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10108551/ (Full text)

Low vitamin D levels are associated with Long COVID syndrome in COVID-19 survivors

Abstract:

Purpose: Long-COVID is an emerging syndrome affecting 50-70% of COVID-19 survivors which still lacks predicting factors. Due to the extra-skeletal effects of vitamin D, we retrospectively assessed in COVID-19 survivors 6-months after hospitalization the association between 25(OH)vitamin D levels and Long-COVID.

Methods: Long-COVID was defined according to NICE-guidelines. Fifty Long-COVID and 50 non-Long-COVID subjects matched on a 1:1-basis were enrolled from an outpatient-post-COVID clinic-cohort seen from August to November 2020. Therapies/comorbidities affecting calcium/vitamin-D/bone metabolism, and/or admission in ICU during hospitalization were exclusion criteria. 25(OH)vitamin D was measured at hospital-admission and 6-months after discharge.

Results: We observed lower 25(OH)vitamin D levels, evaluated at follow-up, in subjects with Long-COVID than those without (20.1vs23.2 ng/mL-p = 0.03). Regarding the affected health-areas evaluated in the entire cohort, we observed lower 25(OH)vitamin D levels in those with neurocognitive symptoms at follow-up (n.7) as compared to those without (n.93) (14.6vs20.6 ng/mL-p = 0.042). In patients presenting vitamin D deficiency (<20 ng/mL) both at admission and at follow-up (n.42), those affected by Long-COVID (n.22) presented lower 25(OH)vitamin D levels, at follow-up, compared to those not affected (n.20) (12.7vs15.2 ng/mL-p = 0.041). In multiple-regression analyses, lower 25(OH)vitamin D levels, at follow-up, resulted as the only variable significantly associated with Long-COVID in our cohort (p = 0.008, OR 1.09-CI 1.01-1.16).

Conclusions: COVID-19 survivors with Long-COVID have lower 25(OH)vitamin D levels as compared to matched-patients without Long-COVID. Our data suggest that vitamin D levels should be evaluated in COVID-19 patients after hospital-discharge. Role of vitamin D supplementation as preventive strategy of COVID-19 sequelae should be tested in randomized-controlled trials.

Source: di Filippo L, Frara S, Nannipieri F, Cotellessa A, Locatelli M, Rovere Querini P, Giustina A. Low vitamin D levels are associated with Long COVID syndrome in COVID-19 survivors. J Clin Endocrinol Metab. 2023 Apr 13:dgad207. doi: 10.1210/clinem/dgad207. Epub ahead of print. PMID: 37051747. https://academic.oup.com/jcem/advance-article/doi/10.1210/clinem/dgad207/7116659 (Full text available as PDF file)

Life changing response to successive surgical interventions on cranial venous outflow: A case report on chronic fatigue syndrome

Abstract:

Recognition of similarities between chronic fatigue syndrome and idiopathic intracranial hypertension (IIH) has raised suggestions that they might be connected, with chronic fatigue syndrome representing a mild version of IIH, sharing many of its symptoms, but without the signature features of elevated intracranial pressure that characterize the complete syndrome.

A further development of this idea factors in the effects of a cerebrospinal fluid leak, a known complication of IIH, to explain cases where symptoms seem out of proportion to the apparent physiological disturbance. Cranial venous outflow obstruction has been proposed as the pathological substrate.

We describe a patient with multiple symptoms, including headache and disabling fatigue, in which this model guided investigation and treatment. Specifically, CT and catheter venography identified focal narrowings of both jugular and the left brachiocephalic veins.

Treatment of brachiocephalic obstruction was not feasible. However, in separate surgical procedures, relief of jugular venous obstruction produced incremental and significant clinical improvements which have proven durable over the length of follow-up.

We suggest that investigating chronic fatigue syndrome under this model might not only bring benefit to individual patients but also will provide new insights into IIH and its relationship with spontaneous intracranial hypotension.

Source: Higgins JNP, Axon PR, Lever AML. Life changing response to successive surgical interventions on cranial venous outflow: A case report on chronic fatigue syndrome. Front Neurol. 2023 Mar 30;14:1127702. doi: 10.3389/fneur.2023.1127702. PMID: 37064208; PMCID: PMC10097901. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10097901/ (Full text)

Cytokine deficiencies in patients with Long-COVID

Abstract:

Up to half of individuals who contract SARS-CoV-2 develop symptoms of long-COVID approximately three months after initial infection. These symptoms are highly variable, and the mechanisms inducing them are yet to be understood. We compared plasma cytokine levels from individuals with long-COVID to healthy individuals and found that those with long-COVID had 100% reductions in circulating levels of Interferon Gamma (IFNγ) and Interleukin-8 (IL-8). Additionally, we found significant reductions in levels of IL-6, IL-2, IL-17, IL-13, and IL-4 in individuals with long-COVID.

We propose immune exhaustion as the driver of long-COVID, with the complete absence of IFNγ and IL-8 preventing the lungs and other organs from healing after acute infection, and reducing the ability to fight off subsequent infections, both contributing to the myriad of symptoms suffered by those with long-COVID.

Source: Williams ES, Martins TB, Shah KS, Hill HR, Coiras M, Spivak AM, Planelles V. Cytokine Deficiencies in Patients with Long-COVID. J Clin Cell Immunol. 2022;13(6):672. Epub 2022 Nov 18. PMID: 36742994; PMCID: PMC9894377. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9894377/ (Full text)

Long COVID: pathophysiological factors and abnormalities of coagulation

Abstract:

Acute COVID-19 infection is followed by prolonged symptoms in approximately one in ten cases: known as Long COVID. The disease affects ~65 million individuals worldwide. Many pathophysiological processes appear to underlie Long COVID, including viral factors (persistence, reactivation, and bacteriophagic action of SARS CoV-2); host factors (chronic inflammation, metabolic and endocrine dysregulation, immune dysregulation, and autoimmunity); and downstream impacts (tissue damage from the initial infection, tissue hypoxia, host dysbiosis, and autonomic nervous system dysfunction). These mechanisms culminate in the long-term persistence of the disorder characterized by a thrombotic endothelialitis, endothelial inflammation, hyperactivated platelets, and fibrinaloid microclots. These abnormalities of blood vessels and coagulation affect every organ system and represent a unifying pathway for the various symptoms of Long COVID.

Source: Simone Turner, Asad Khan, David Putrino, Ashley Woodcock, Douglas B. Kell, and Etheresia Pretorius.  Long COVID: pathophysiological factors and abnormalities of coagulation. Trends in Endocrinology & Metabolism. April 19, 2023. https://www.sciencedirect.com/science/article/pii/S1043276023000553 (Full text)

Symptom persistence and biomarkers in post-COVID-19/chronic fatigue syndrome – results from a prospective observational cohort

Abstract:

Introduction: Post-COVID-19 syndrome (PCS) is characterized by a wide range of symptoms, predominantly fatigue and exertional intolerance. While disease courses during the first year post infection have been repeatedly described, little is known about long-term health consequences.

Methods: We assessed symptom severity and various biomarkers at three time points post infection (3-8 months (mo), 9-16mo, 17-20mo) in 106 PCS patients with moderate to severe fatigue and exertional intolerance. A subset of patients fulfilled diagnostic criteria of myalgic encephalomyelitis/chronic fatigue syndrome (PCS-ME/CFS) based on the Canadian Consensus Criteria.

Results: While PCS-ME/CFS patients showed persisting symptom severity and disability up to 20mo post infection, PCS patients reported an overall health improvement. Inflammatory biomarkers equally decreased in both groups. Lower hand grip force at onset correlated with symptom persistence especially in PCS-ME/CFS.

Discussion: Debilitating PCS may persist beyond 20mo post infection, particularly in patients fulfilling diagnostic criteria for ME/CFS.

Source: Anna Franziska Legler, Lil Meyer-Arndt, Lukas Moedl, Claudia Kedor, Helma Freitag, Elena Steinle, Uta Hoppmann, Rebekka Rust, Frank Konietschke, Andreas Thiel, Friedemann Paul, Carmen Scheibenbogen, Judith Bellmann-Strobl. Symptom persistence and biomarkers in post-COVID-19/chronic fatigue syndrome – results from a prospective observational cohort.
medRxiv 2023.04.15.23288582; doi: https://doi.org/10.1101/2023.04.15.23288582 (Full text available as PDF file)

A review of cytokine-based pathophysiology of Long COVID symptoms

Abstract:

The Long COVID/Post Acute Sequelae of COVID-19 (PASC) group includes patients with initial mild-to-moderate symptoms during the acute phase of the illness, in whom recovery is prolonged, or new symptoms are developed over months. Here, we propose a description of the pathophysiology of the Long COVID presentation based on inflammatory cytokine cascades and the p38 MAP kinase signaling pathways that regulate cytokine production.

In this model, the SARS-CoV-2 viral infection is hypothesized to trigger a dysregulated peripheral immune system activation with subsequent cytokine release. Chronic low-grade inflammation leads to dysregulated brain microglia with an exaggerated release of central cytokines, producing neuroinflammation. Immunothrombosis linked to chronic inflammation with microclot formation leads to decreased tissue perfusion and ischemia. Intermittent fatigue, Post Exertional Malaise (PEM), CNS symptoms with “brain fog,” arthralgias, paresthesias, dysautonomia, and GI and ophthalmic problems can consequently arise as result of the elevated peripheral and central cytokines.

There are abundant similarities between symptoms in Long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). DNA polymorphisms and viral-induced epigenetic changes to cytokine gene expression may lead to chronic inflammation in Long COVID patients, predisposing some to develop autoimmunity, which may be the gateway to ME/CFS.

Source: Low RN, Low RJ, Akrami A. A review of cytokine-based pathophysiology of Long COVID symptoms. Front Med (Lausanne). 2023 Mar 31;10:1011936. doi: 10.3389/fmed.2023.1011936. PMID: 37064029; PMCID: PMC10103649. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10103649/ (Full text)

The Breadth of the Neutralizing Antibody Response to Original SARS-CoV-2 Infection is Linked to the Presence of Long COVID Symptoms

Abstract:

Background: The associations between longitudinal dynamics and the breadth of SARS-CoV-2 neutralizing antibody response with various Long COVID (LC) phenotypes prior to vaccination are not known. The capacity of antibodies to cross neutralize a variety of viral variants may be associated with ongoing pathology and persistent symptoms.

Methods: We measured longitudinal neutralizing and cross-neutralizing antibody responses to pre- and post-SARS-CoV-2 Omicron variants in participants infected during the early waves of the COVID-19 pandemic, prior to wide-spread rollout of SARS-CoV-2 vaccines. Cross sectional regression models adjusted for various clinical covariates and longitudinal mixed effects models were used to determine the impact of the breadth and rate of decay of neutralizing responses on the development of Long COVID symptoms in general, as well as LC phenotypes.

Results: We identified several novel relationships between SARS-CoV-2 antibody neutralization and the presence of LC symptoms. Specifically, we show that, although neutralizing antibody responses to the original, infecting strain of SARS-CoV-2 were not associated with LC in cross-sectional analyses, cross-neutralization ID50 levels to the Omicron BA.5 variant approximately 4 months following acute infection was independently and significantly associated with greater odds of LC and with persistent gastrointestinal and neurological symptoms. Longitudinal modeling demonstrated significant associations in the overall levels and rates of decay of neutralization capacity with LC phenotypes. A higher proportion of participants had antibodies capable of neutralizing Omicron BA.5 compared with BA.1 or XBB.1.5 variants.

Conclusions: Our findings suggest that relationships between various immune responses and LC are likely complex but may involve the breadth of antibody neutralization responses.

Source: Buck AM, Deitchman AN, Takahashi S, Lu S, Goldberg SA, Hoh R, Williams MC, Kerbleski M, Deveau TM, Munter SE, Lombardo J, Wrin T, Petropoulos CJ, Durstenfeld MS, Hsue PY, Kelly JD, Greenhouse B, Martin JN, Deeks SG, Peluso MJ, Henrich TJ. The Breadth of the Neutralizing Antibody Response to Original SARS-CoV-2 Infection is Linked to the Presence of Long COVID Symptoms. medRxiv [Preprint]. 2023 Mar 31:2023.03.30.23287923. doi: 10.1101/2023.03.30.23287923. PMID: 37034660; PMCID: PMC10081395. https://www.medrxiv.org/content/10.1101/2023.03.30.23287923v1.full-text (Full text)