Plasma cytokine levels reveal deficiencies in IL-8 and gamma interferon in 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 ESCP, Martins TB, Hill HR, Coiras M, Shah KS, Planelles V, Spivak AM. Plasma cytokine levels reveal deficiencies in IL-8 and gamma interferon in Long-COVID. medRxiv [Preprint]. 2022 Oct 5:2022.10.03.22280661. doi: 10.1101/2022.10.03.22280661. PMID: 36238724; PMCID: PMC9558442. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9558442/ (Full text)

Pathophysiology of Post-COVID syndromes: a new perspective

Abstract:

Most COVID-19 patients recovered with low mortality; however, some patients experienced long-term symptoms described as “long-COVID” or “Post-COVID syndrome” (PCS). Patients may have persisting symptoms for weeks after acute SARS-CoV-2 infection, including dyspnea, fatigue, myalgia, insomnia, cognitive and olfactory disorders. These symptoms may last for months in some patients.

PCS may progress in association with the development of mast cell activation syndrome (MCAS), which is a distinct kind of mast cell activation disorder, characterized by hyper-activation of mast cells with inappropriate and excessive release of chemical mediators. COVID-19 survivors, mainly women, and patients with persistent severe fatigue for 10 weeks after recovery with a history of neuropsychiatric disorders are more prone to develop PCS. High D-dimer levels and blood urea nitrogen were observed to be risk factors associated with pulmonary dysfunction in COVID-19 survivors 3 months post-hospital discharge with the development of PCS. PCS has systemic manifestations that resolve with time with no further complications. However, the final outcomes of PCS are chiefly unknown.

Persistence of inflammatory reactions, autoimmune mimicry, and reactivation of pathogens together with host microbiome alterations may contribute to the development of PCS. The deregulated release of inflammatory mediators in MCAS produces extraordinary symptoms in patients with PCS. The development of MCAS during the course of SARS-CoV-2 infection is correlated to COVID-19 severity and the development of PCS. Therefore, MCAS is treated by antihistamines, inhibition of synthesis of mediators, inhibition of mediator release, and inhibition of degranulation of mast cells.

Source: Batiha, G.ES., Al-kuraishy, H.M., Al-Gareeb, A.I. et al. Pathophysiology of Post-COVID syndromes: a new perspective. Virol J 19, 158 (2022). https://doi.org/10.1186/s12985-022-01891-2  https://virologyj.biomedcentral.com/articles/10.1186/s12985-022-01891-2 (Full text)

Sleep symptoms are essential features of long-COVID – Comparing healthy controls with COVID-19 cases of different severity in the international COVID sleep study (ICOSS-II)

Abstract:

Many people report suffering from post-acute sequelae of COVID-19 or “long-COVID”, but there are still open questions on what actually constitutes long-COVID and how prevalent it is. The current definition of post-acute sequelae of COVID-19 is based on voting using the Delphi-method by the WHO post-COVID-19 working group. It emphasizes long-lasting fatigue, shortness of breath and cognitive dysfunction as the core symptoms of post-acute sequelae of COVID-19.

In this international survey study consisting of 13,628 subjects aged 18-99 years from 16 countries of Asia, Europe, North America and South America (May-Dec 2021), we show that post-acute sequelae of COVID-19 symptoms were more prevalent amongst the more severe COVID-19 cases, i.e. those requiring hospitalisation for COVID-19. We also found that long-lasting sleep symptoms are at the core of post-acute sequelae of COVID-19 and associate with the COVID-19 severity when COVID-19 cases are compared with COVID-negative cases.

Specifically, fatigue (61.3%), insomnia symptoms (49.6%) and excessive daytime sleepiness (35.8%) were highly prevalent amongst respondents reporting long-lasting symptoms after hospitalisation for COVID-19. Understanding the importance of sleep-related symptoms in post-acute sequelae of COVID-19 has a clinical relevance when diagnosing and treating long-COVID.

Source: Merikanto I, Dauvilliers Y, Chung F, Wing YK, de Gennaro L, Holzinger B, Bjorvatn B, Morin CM, Penzel T, Benedict C, Koscec Bjelajac A, Chan NY, Espie CA, Hrubos-Strøm H, Inoue Y, Korman M, Landtblom AM, Léger D, Matsui K, Mota-Rolim S, Nadorff MR, Plazzi G, Reis C, Yordanova J, Partinen M. Sleep symptoms are essential features of long-COVID – Comparing healthy controls with COVID-19 cases of different severity in the international COVID sleep study (ICOSS-II). J Sleep Res. 2022 Oct 8:e13754. doi: 10.1111/jsr.13754. Epub ahead of print. PMID: 36208038. https://onlinelibrary.wiley.com/doi/10.1111/jsr.13754 (Full text)

Grief in Chronic Illness: A Case Study of CFS/ME

Abstract:

This paper points to a more expansive conception of grief by arguing that the losses of illness can be genuine objects of grief.

I argue for this by illuminating underappreciated structural features of typical grief — that is, grief over a bereavement — which are shared but under-recognized. I offer a common chronic illness, chronic fatigue syndrome/myalgic encephalomyelitis (CFS/ME), as a striking case study.

I then use this analysis to highlight some clinical challenges that arise should this claim receive uptake in clinical practice.

Extant literature on CFS/ME tells us that rates of comorbid depression are atypically high. If one accepts that people with CFS/ ME can grieve over losses associated with the condition, and that grief can be easily mistaken for depression in this context, this might suggest that rates of comorbid depression are inflated.

I show, however, that the challenge of distinguishing between healthy and pathological grief arises in its place, and is just as tricky to solve.

Source: Byrne, Eleanor Alexandra. Grief in Chronic Illness: A Case Study of CFS/ME. Journal of Consciousness Studies, Volume 29, Numbers 9-10, September 2022, pp. 175-200(26). https://www.ingentaconnect.com/contentone/imp/jcs/2022/00000029/f0020009/art00009

Symptomatology and microbiology of the gastrointestinal tract in post-COVID conditions

Abstract:

Post-COVID conditions, also known as post-acute sequelae of SARS-CoV-2 (PASC), refer to the persistence of symptoms in COVID-19 long-haulers. Various manifestations of post-COVID conditions are general symptoms and/or manifestations of damage in multiple organs. Besides, SARS-CoV-2 can involve the gastrointestinal tract, resulting in sequelae such as diarrhea, abdominal pain, nausea, anorexia, vomiting, constipation, abdominal distension, acid reflux, and/or gastrointestinal bleeding.
Previous investigations point to SARS-CoV-2 entry into enterocytes enhances by the angiotensin-converting enzyme 2 (ACE2) receptors. Interestingly, ACE2 receptors are abundantly expressed in the gut, implying infection with SARS-CoV-2 might occur through this route as well as in the respiratory tract. According to mounting evidence, SARS-CoV-2 RNA has been identified in fecal specimens of patients with COVID-19 during and beyond the acute phase.
In addition, studies have shown gut microbiome composition is altered in patients with PASC, hence, another putative mechanism linked to gastrointestinal symptoms is gut dysbiosis. The presence of the gut-lung axis in COVID-19 might have major implications for disease pathogenesis and treatment.
This review discussed the prevalence of gastrointestinal symptoms and pathophysiology underlying possible infection of the gut in patients with PASC. Also, SARS-COV-2 induced NLRP3 inflammasome-dependent inflammatory pathways are briefly addressed.
Source: Norouzi Masir M, Shirvaliloo M. Symptomatology and microbiology of the gastrointestinal tract in post-COVID conditions. JGH Open : an Open Access Journal of Gastroenterology and Hepatology. 2022 Aug. DOI: 10.1002/jgh3.12811. PMID: 36247234; PMCID: PMC9538198. https://europepmc.org/article/pmc/pmc9538198 (Full text)

Saliva antibody-fingerprint of reactivated latent viruses after mild/asymptomatic COVID-19 is unique in patients with myalgic-encephalomyelitis/chronic fatigue syndrome

Abstract:

Background: Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a chronic disease considered to be triggered by viral infections in a majority of cases. Symptoms overlap largely with those of post-acute sequelae of COVID-19/long-COVID implying common pathogenetic mechanisms. SARS-CoV-2 infection is risk factor for sustained latent virus reactivation that may account for the symptoms of post-viral fatigue syndromes. The aim of this study was first to investigate whether patients with ME/CFS and healthy donors (HDs) differed in their antibody response to mild/asymptomatic SARS-CoV-2 infection. Secondly, to analyze whether COVID-19 imposes latent virus reactivation in the cohorts.

Methods: Anti-SARS-CoV-2 antibodies were analyzed in plasma and saliva from non-vaccinated ME/CFS (n=95) and HDs (n=110) using soluble multiplex immunoassay. Reactivation of human herpesviruses 1-6 (HSV1, HSV2, VZV, EBV, CMV, HHV6), and human endogenous retrovirus K (HERV-K) was detected by anti-viral antibody fingerprints in saliva.

Results: At 3-6 months after mild/asymptomatic SARS-CoV-2 infection, virus-specific antibodies in saliva were substantially induced signifying a strong reactivation of latent viruses (EBV, HHV6 and HERV-K) in both cohorts. In patients with ME/CFS, antibody responses were significantly stronger, in particular EBV-encoded nuclear antigen-1 (EBNA1) IgG were elevated in patients with ME/CFS, but not in HDs. EBV-VCA IgG was also elevated at baseline prior to SARS-infection in patients compared to HDs.

Conclusion: Our results denote an altered and chronically aroused anti-viral profile against latent viruses in ME/CFS. SARS-CoV-2 infection even in its mild/asymptomatic form is a potent trigger for reactivation of latent herpesviruses (EBV, HHV6) and endogenous retroviruses (HERV-K), as detected by antibody fingerprints locally in the oral mucosa (saliva samples). This has not been shown before because the antibody elevation is not detected systemically in the circulation/plasma.

Source: Apostolou Eirini, Rizwan Muhammad, Moustardas Petros, Sjögren Per, Bertilson Bo Christer, Bragée Björn, Polo Olli, Rosén Anders. Saliva antibody-fingerprint of reactivated latent viruses after mild/asymptomatic COVID-19 is unique in patients with myalgic-encephalomyelitis/chronic fatigue syndrome. Frontiers in Immunology, Vol 13, 2022. https://www.frontiersin.org/articles/10.3389/fimmu.2022.949787/full (Full text)

Factors Influencing the Prognosis of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a long-term debilitating multisystem condition with poor prognosis. Studies that examined predictors of ME/CFS outcomes yielded contradictory results. We aimed to explore epidemiological and clinical prognostic factors of ME/CFS using operationalized criteria for recovery/improvement.
Adult ME/CFS patients who attended the Internal Medicine Department of Angers University Hospital, Angers, France between October 2011 and December 2019, and were followed up until December 2020, were included retrospectively. Their medical records were reviewed for data collection. Patients were classified into two groups according to the presence or absence of recovery/improvement (R/I) and compared for epidemiological characteristics, fatigue features, post-exertional malaise severity, clinical manifestations, and comorbidities.
The subgroups of recovered and significantly improved patients were then compared. 168 patients were included. Recovery and improvement rates were 8.3% and 4.8%, respectively. Older age at disease onset was associated with R/I (OR 1.06 [95% CI 1.007–1.110] (= 0.028)), while diagnostic delay was inversely associated with R/I (OR 0.98 [95% CI 0.964–0.996] (= 0.036)). The study findings confirmed the poor prognosis of ME/CFS and the deleterious effect of diagnostic delay on disease progression. Interestingly, being older at disease onset was associated with better outcomes, which offers hope to patients for recovery/improvement even at an advanced age.
Source: Ghali A, Lacout C, Fortrat J-O, Depres K, Ghali M, Lavigne C. Factors Influencing the Prognosis of Patients with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Diagnostics. 2022; 12(10):2540. https://doi.org/10.3390/diagnostics12102540  https://www.mdpi.com/2075-4418/12/10/2540 (Full text available as PDF file)

Endothelial dysfunction in COVID-19: an overview of evidence, biomarkers, mechanisms and potential therapies

Abstract:

The fight against coronavirus disease 2019 (COVID-19) caused by SARS-CoV-2 infection is still raging. However, the pathophysiology of acute and post-acute manifestations of COVID-19 (long COVID-19) is understudied. Endothelial cells are sentinels lining the innermost layer of blood vessel that gatekeep micro- and macro-vascular health by sensing pathogen/danger signals and secreting vasoactive molecules. SARS-CoV-2 infection primarily affects the pulmonary system, but accumulating evidence suggests that it also affects the pan-vasculature in the extrapulmonary systems by directly (via virus infection) or indirectly (via cytokine storm), causing endothelial dysfunction (endotheliitis, endothelialitis and endotheliopathy) and multi-organ injury.

Mounting evidence suggests that SARS-CoV-2 infection leads to multiple instances of endothelial dysfunction, including reduced nitric oxide (NO) bioavailability, oxidative stress, endothelial injury, glycocalyx/barrier disruption, hyperpermeability, inflammation/leukocyte adhesion, senescence, endothelial-to-mesenchymal transition (EndoMT), hypercoagulability, thrombosis and many others. Thus, COVID-19 is deemed as a (micro)vascular and endothelial disease. Of translational relevance, several candidate drugs which are endothelial protective have been shown to improve clinical manifestations of COVID-19 patients.

The purpose of this review is to provide a latest summary of biomarkers associated with endothelial cell activation in COVID-19 and offer mechanistic insights into the molecular basis of endothelial activation/dysfunction in macro- and micro-vasculature of COVID-19 patients. We envisage further development of cellular models and suitable animal models mimicking endothelial dysfunction aspect of COVID-19 being able to accelerate the discovery of new drugs targeting endothelial dysfunction in pan-vasculature from COVID-19 patients.

Source: Xu, Sw., Ilyas, I. & Weng, Jp. Endothelial dysfunction in COVID-19: an overview of evidence, biomarkers, mechanisms and potential therapies. Acta Pharmacol Sin (2022). https://doi.org/10.1038/s41401-022-00998-0 https://www.nature.com/articles/s41401-022-00998-0 (Full text)

New‑onset neuropsychiatric sequelae and ‘long‑COVID’ syndrome (Review)

Abstract:

The ongoing coronavirus disease 2019 (COVID‑19) pandemic has had a widespread impact on individuals’ mental health through indirect psychological and social mechanisms, related to factors such as fear of infection or death, social isolation, lack of social support and financial instability.
The severe acute respiratory syndrome coronavirus 2 (SARS‑CoV‑2) infection has also been associated with the development or recurrence of neuropsychiatric symptoms, both during the acute phase, as well as during the post‑acute ‘long‑COVID’ phase. In addition to the COVID‑19 survivors with a mental health history that are at a high risk of experiencing a range of neuropsychiatric symptoms following resolution of acute COVID‑19, there is accumulating evidence that a diagnosis of COVID‑19 may also be associated with new‑onset neuropsychiatric morbidity among survivors without pre‑existing mental health disorders.
In particular, studies investigating the incidence of post‑acute neuropsychiatric sequelae, based mostly on retrospective cohort study designs and data from national health registries, have reported the development of new‑onset manifestations, including depression, anxiety, psychotic symptoms, sleep disturbances and fatigue. Nevertheless, when COVID‑19 survivors were compared with SARS‑CoV‑2‑negative controls and especially survivors of other disorders (such as influenza), the findings regarding the risk of incident neuropsychiatric manifestations varied among studies.
While there is evidence of an association between SARS‑CoV‑2 infection and the subsequent occurrence of new‑onset neuropsychiatric symptoms, especially among patients with increased disease severity, further research using methodological approaches less susceptible to confounding bias is required to establish causal relationships.
Source: Efstathiou, V., Stefanou, M., Demetriou, M., Siafakas, N., Katsantoni, E., Makris, M., Tsivgoulis, G., Zoumpourlis, V., Kympouropoulos, S. P., Tsoporis, J. N., Spandidos, D. A., Ferentinos, P., Smyrnis, N., Rizos, E.”New‑onset neuropsychiatric sequelae and ‘long‑COVID’ syndrome (Review)”. Experimental and Therapeutic Medicine 24.5 (2022): 705. https://www.spandidos-publications.com/10.3892/etm.2022.11641 (Full text available as PDF file)

Elevated vascular transformation blood biomarkers in Long-COVID indicate angiogenesis as a key pathophysiological mechanism

Abstract:

Background: Long-COVID is characterized by prolonged, diffuse symptoms months after acute COVID-19. Accurate diagnosis and targeted therapies for Long-COVID are lacking. We investigated vascular transformation biomarkers in Long-COVID patients.

Methods: A case–control study utilizing Long-COVID patients, one to six months (median 98.5 days) post-infection, with multiplex immunoassay measurement of sixteen blood biomarkers of vascular transformation, including ANG-1, P-SEL, MMP-1, VE-Cad, Syn-1, Endoglin, PECAM-1, VEGF-A, ICAM-1, VLA-4, E-SEL, thrombomodulin, VEGF-R2, VEGF-R3, VCAM-1 and VEGF-D.

Results: Fourteen vasculature transformation blood biomarkers were significantly elevated in Long-COVID outpatients, versus acutely ill COVID-19 inpatients and healthy controls subjects (P < 0.05). A unique two biomarker profile consisting of ANG-1/P-SEL was developed with machine learning, providing a classification accuracy for Long-COVID status of 96%. Individually, ANG-1 and P-SEL had excellent sensitivity and specificity for Long-COVID status (AUC = 1.00, P < 0.0001; validated in a secondary cohort). Specific to Long-COVID, ANG-1 levels were associated with female sex and a lack of disease interventions at follow-up (P < 0.05).

Conclusions: Long-COVID patients suffer prolonged, diffuse symptoms and poorer health. Vascular transformation blood biomarkers were significantly elevated in Long-COVID, with angiogenesis markers (ANG-1/P-SEL) providing classification accuracy of 96%. Vascular transformation blood biomarkers hold potential for diagnostics, and modulators of angiogenesis may have therapeutic efficacy.

Source: Patel, M.A., Knauer, M.J., Nicholson, M. et al. Elevated vascular transformation blood biomarkers in Long-COVID indicate angiogenesis as a key pathophysiological mechanism. Mol Med 28, 122 (2022). https://doi.org/10.1186/s10020-022-00548-8 https://molmed.biomedcentral.com/articles/10.1186/s10020-022-00548-8 (Full text)