Tag: mast cell activation syndrome

Biological mechanisms underpinning the development of Long COVID

Abstract:

As COVID-19 evolves from a pandemic to an endemic disease, the already staggering number of people that have been or will be infected with SARS-COV-2 is only destined to increase, and the majority of humanity will be infected. It is well understood that COVID-19, like many other viral infections, leaves a significant fraction of the infected with prolonged consequences.

Continued high number of SARS-CoV-2 infections, viral evolution with escape from post-infection and vaccinal immunity, and reinfections heighten the potential impact of Long COVID. Hence, the impact of COVID-19 on human health will be seen for years to come until more effective vaccines and pharmaceutical treatments become available.

To that effect, it is imperative that the mechanisms underlying the clinical manifestations of Long COVID be elucidated. In this article, we provide an in-depth analysis of the evidence on several potential mechanisms of Long COVID and discuss their relevance to its pathogenesis.

Source: Perumal R, Shunmugam L, Naidoo K, Wilkins D, Garzino-Demo A, Brechot C, Vahlne A, Nikolich J. Biological mechanisms underpinning the development of Long COVID. iScience. 2023 May 18:106935. doi: 10.1016/j.isci.2023.106935. Epub ahead of print. PMCID: PMC10193768. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10193768/ https://www.cell.com/iscience/pdf/S2589-0042(23)01012-X.pdf?_returnURL=https%3A%2F%2Flinkinghub.elsevier.com%2Fretrieve%2Fpii%2FS258900422301012X%3Fshowall%3Dtrue (Full text)

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Comorbidities: Linked by Vascular Pathomechanisms and Vasoactive Mediators?

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is often associated with various other syndromes or conditions including mast cell activation (MCA), dysmenorrhea and endometriosis, postural tachycardia (POTS) and small fiber neuropathy (SFN). The causes of these syndromes and the reason for their frequent association are not yet fully understood.

We previously published a comprehensive hypothesis of the ME/CFS pathophysiology that explains the majority of symptoms, findings and chronicity of the disease. We wondered whether some of the identified key pathomechanisms in ME/CFS are also operative in MCA, endometriosis and dysmenorrhea, POTS, decreased cerebral blood flow and SFN, and possibly may provide clues on their causes and frequent co-occurrence.

Our analysis indeed provides strong arguments in favor of this assumption, and we conclude that the main pathomechanisms responsible for this association are excessive generation and spillover into the systemic circulation of inflammatory and vasoactive tissue mediators, dysfunctional β2AdR, and the mutual triggering of symptomatology and disease initiation. Overall, vascular dysfunction appears to be a strong common denominator in these linkages.

Source: Wirth KJ, Löhn M. Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) and Comorbidities: Linked by Vascular Pathomechanisms and Vasoactive Mediators? Medicina. 2023; 59(5):978. https://doi.org/10.3390/medicina59050978  https://www.mdpi.com/1648-9144/59/5/978 (Full text)

Immunological dysfunction and mast cell activation syndrome in long COVID

Abstract:

At least 65 million people around the world suffer from long COVID, with the majority of cases occurring in the productive age (36–50 years old). Individuals with long COVID are confounded with multiple organ system dysfunctions, long-term organ injury sequelae, and a decreased quality of life. There is an overlapping of risk factors between long COVID and other postviral infection syndromes, so advances in research could also benefit other groups of patients.

Long COVID is the consequence of multiple immune system dysregulation, such as T-cell depletion, innate immune cell hyperactivity, lack of naive T and B cells, and elevated signature of pro-inflammatory cytokines, together with persistent SARS-CoV2 reservoir and other consequences of acute infection.

There is an activated condition of mast cells in long COVID, with abnormal granulation and excessive inflammatory cytokine release. A study by Weinstock et al. indicates that patients with long COVID suffer the same clinical syndrome as patients with mast cell activation syndrome (MCAS).

Diagnosis and treatment of MCAS in patients with long COVID will provide further symptomatic relief, and manage mast cell-mediated hyperinflammation states, which could be useful in the long-term control and recovery of such patients.

Source: Sumantri, Stevent; Rengganis, Iris. Immunological dysfunction and mast cell activation syndrome in long COVID. Asia Pacific Allergy ():10.5415/apallergy.0000000000000022, March 30, 2023. | DOI: 10.5415/apallergy.0000000000000022 https://journals.lww.com/apallergy/Fulltext/9900/Immunological_dysfunction_and_mast_cell_activation.2.aspx (Full text)

Cardiovascular Considerations in the Management of People with Suspected Long COVID

Abstract:

Approximately 15% of adult Canadians with SARS-CoV-2 infection develop lingering symptoms beyond 12 weeks post-acute infection, known as post-COVID condition or long COVID. Some of the commonly reported long COVID cardiovascular symptoms include fatigue, shortness of breath, chest pain, and palpitations. Suspected long-term cardiovascular complications of SARS-CoV-2 infection may present as a constellation of symptoms that can be challenging for clinicians to diagnose and treat.

When assessing patients with these symptoms, clinicians need to keep in mind Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), post-exertional malaise and post-exertional symptom exacerbation (PEM/PESE), cardiac dysautonomia such as Inappropriate Sinus Tachycardia (IST), and Postural Orthostatic Tachycardia Syndrome (POTS), and occasionally Mast Cell Activation Syndrome (MCAS).

This paper summarizes the globally evolving evidence around management of cardiac sequelae of long COVID. In addition, this review includes a Canadian perspective, consisting of a panel of expert opinions from experienced clinicians across Canada who have been involved in management of long COVID. The objective of this review is to offer some practical guidance to cardiologists and generalist clinicians regarding diagnostic and treatment approaches for adult patients with suspected long COVID who continue to experience unexplained cardiac symptoms.

Source: Quinn KL, Lam GY, Walsh JF, Bhéreur A, Brown AD, Chow CW, Christie Chung KY, Cowan J, Crampton N, Décary S, Falcone EL, Graves L, Gross DP, Hanneman K, Harvey PJ, Holmes S, Katz GM, Parhizgar P, Sharkawy A, Tran KC, Waserman S, Zannella VE, Cheung AM. Cardiovascular Considerations in the Management of People with Suspected Long COVID. Can J Cardiol. 2023 Apr 6:S0828-282X(23)00303-3. doi: 10.1016/j.cjca.2023.04.003. Epub ahead of print. PMID: 37030518. Quinn KL, Lam GY, Walsh JF, Bhéreur A, Brown AD, Chow CW, Christie Chung KY, Cowan J, Crampton N, Décary S, Falcone EL, Graves L, Gross DP, Hanneman K, Harvey PJ, Holmes S, Katz GM, Parhizgar P, Sharkawy A, Tran KC, Waserman S, Zannella VE, Cheung AM. Cardiovascular Considerations in the Management of People with Suspected Long COVID. Can J Cardiol. 2023 Apr 6:S0828-282X(23)00303-3. doi: 10.1016/j.cjca.2023.04.003. Epub ahead of print. PMID: 37030518. https://www.onlinecjc.ca/article/S0828-282X(23)00303-3/fulltext (Full text)

A Case Study of Successful Application of the Principles of ME/CFS Care to an Individual with Long COVID

Abstract:

Persistent fatigue is one of the most common symptoms of post-COVID conditions, also termed long COVID. At the extreme end of the severity spectrum, some individuals with long COVID also meet the criteria for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), raising the possibility that symptom management approaches for ME/CFS may benefit some long COVID patients.

We describe the long-term outcomes of a 19-year-old male who developed profound impairment consistent with ME/CFS after a SARS-CoV-2 infection early in the pandemic.

We evaluated and treated him using our clinic’s approach to ME/CFS. This included a history and physical examination that ascertained joint hypermobility, pathological reflexes, physical therapy maneuvers to look for a range of motion restrictions in the limbs and spine, orthostatic testing, and screening laboratory studies.

He was found to have profound postural tachycardia syndrome, several ranges of motion restrictions, and mast cell activation syndrome. He was treated according to our clinic’s guidelines for managing ME/CFS, which included manual physical therapy maneuvers and both non-pharmacologic measures and medications directed at postural tachycardia syndrome and mast cell activation.

He experienced significant improvement in his symptoms over 30 months. His case emphasizes how the application of the principles of treating ME/CFS has the potential to provide a direction for treating long COVID.

Source: Petracek LS, Broussard CA, Swope RL, Rowe PC. A Case Study of Successful Application of the Principles of ME/CFS Care to an Individual with Long COVID. Healthcare. 2023; 11(6):865. https://doi.org/10.3390/healthcare11060865 (Full text)

Antioxidants and Long Covid

Abstract:

Long Covid has many symptoms that overlap with ME(myalgic encephalomyelitis)/CFS(chronic fatigue syndrome), FM(fibromyalgia), EBV(Epstein-Barr virus), CMV(cytomegalovirus), CIRS (chronic inflammatory response syndrome), MCAS(mast cell activation syndrome), POTS(postural orthostatic tachycardia syndrome), and post viral fatigue syndrome. They all portend a “long haul” with an antioxidant shortfall and elevated Ca:Mg. Oxidative stress is the root cause.

Linkage between TGF(transforming growth factor)-β, IFN(interferon)-γ, the RAS(renin angiotensin system), and the KKS(kallikrein kinin system) is discussed. Technical explanations for the renin aldosterone paradox in POTS, the betrayal of TGF-β, and the commonality of markers for the Warburg effect are offered. The etiology of the common Long Covid symptoms of post exertional malaise, fatigue, and brain fog as well as anosmia, hair loss, and GI symptoms is technically discussed. Ca:Mg is critical to the glutamate/GABA balance. The role of GABA and butyrates from the “good” intestinal bacteria in the gut-brain axis and its correlation with chronic fatigue diseases are explored.

The crosstalk between the ENS(enteric nervous system) and the ANS(autonomic nervous system) and the role of the vagus in both are emphasized. HRV(heart rate variability), the fifth vital sign, points to an expanded gut-brain-heart/lung axis. A suggested approach to all of these – Long Covid, chronic fatigue diseases, post viral fatigue syndrome, and general health – is presented.

Source: Chambers, P. Antioxidants and Long Covid. Preprints 2022, 2022100195 (doi: 10.20944/preprints202210.0195.v1).  https://www.preprints.org/manuscript/202210.0195/v1 (Full text available as PDF file)

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)

The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications

Abstract:

Ischaemia-reperfusion (I-R) injury, initiated via bursts of reactive oxygen species produced during the reoxygenation phase following hypoxia, is well known in a variety of acute circumstances. We argue here that I-R injury also underpins elements of the pathology of a variety of chronic, inflammatory diseases, including rheumatoid arthritis, ME/CFS and, our chief focus and most proximally, Long COVID.

Ischaemia may be initiated via fibrin amyloid microclot blockage of capillaries, for instance as exercise is started; reperfusion is a necessary corollary when it finishes. We rehearse the mechanistic evidence for these occurrences here, in terms of their manifestation as oxidative stress, hyperinflammation, mast cell activation, the production of marker metabolites and related activities.

Such microclot-based phenomena can explain both the breathlessness/fatigue and the post-exertional malaise that may be observed in these conditions, as well as many other observables. The recognition of these processes implies, mechanistically, that therapeutic benefit is potentially to be had from antioxidants, from anti-inflammatories, from iron chelators, and via suitable, safe fibrinolytics, and/or anti-clotting agents. We review the considerable existing evidence that is consistent with this, and with the biochemical mechanisms involved.

Source: Kell DB, Pretorius E. The potential role of ischaemia-reperfusion injury in chronic, relapsing diseases such as rheumatoid arthritis, Long COVID, and ME/CFS: evidence, mechanisms, and therapeutic implications. Biochem J. 2022 Aug 31;479(16):1653-1708. doi: 10.1042/BCJ20220154. PMID: 36043493. https://portlandpress.com/biochemj/article/479/16/1653/231696/The-potential-role-of-ischaemia-reperfusion-injury (Full text)

Mast cell activation syndrome and the link with long COVID

Abstract:

Mast cells are innate immune cells found in connective tissues throughout the body, most prevalent at tissue-environment interfaces. They possess multiple cell-surface receptors which react to various stimuli and, after activation, release many mediators including histamine, heparin, cytokines, prostaglandins, leukotrienes and proteases.

In mast cell activation syndrome, excessive amounts of inflammatory mediators are released in response to triggers such as foods, fragrances, stress, exercise, medications or temperature changes. Diagnostic markers may be difficult to assess because of their rapid degradation; these include urinary N-methyl histamine, urinary prostaglandins D2, DM and F2α and serum tryptase (which is stable) in the UK. Self-management techniques, medications and avoiding triggers may improve quality of life. Treatments include mast cell mediator blockers, mast cell stabilisers and anti-inflammatory agents. ‘Long COVID’ describes post-COVID-19 syndrome when symptoms persist for more than 12 weeks after initial infection with no alternative diagnosis.

Both mast cell activation syndrome and long COVID cause multiple symptoms. It is theorised that COVID-19 infection could lead to exaggeration of existing undiagnosed mast cell activation syndrome, or could activate normal mast cells owing to the persistence of viral particles. Other similarities include the relapse-remission cycle and improvements with similar treatments. Importantly, however, aside from mast cell disorders, long COVID could potentially be attributed to several other conditions.

Source: Arun S, Storan A, Myers B. Mast cell activation syndrome and the link with long COVID. Br J Hosp Med (Lond). 2022 Jul 2;83(7):1-10. doi: 10.12968/hmed.2022.0123. Epub 2022 Jul 26. PMID: 35938771. https://pubmed.ncbi.nlm.nih.gov/35938771/

Long-COVID syndrome-associated brain fog and chemofog: Luteolin to the rescue

Abstract:

COVID-19 leads to severe respiratory problems, but also to long-COVID syndrome associated primarily with cognitive dysfunction and fatigue. Long-COVID syndrome symptoms, especially brain fog, are similar to those experienced by patients undertaking or following chemotherapy for cancer (chemofog or chemobrain), as well in patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) or mast cell activation syndrome (MCAS). The pathogenesis of brain fog in these illnesses is presently unknown but may involve neuroinflammation via mast cells stimulated by pathogenic and stress stimuli to release mediators that activate microglia and lead to inflammation in the hypothalamus. These processes could be mitigated by phytosomal formulation (in olive pomace oil) of the natural flavonoid luteolin.

Source: Theoharides TC, Cholevas C, Polyzoidis K, Politis A. Long-COVID syndrome-associated brain fog and chemofog: Luteolin to the rescue. Biofactors. 2021 Apr 12. doi: 10.1002/biof.1726. Epub ahead of print. PMID: 33847020. https://pubmed.ncbi.nlm.nih.gov/33847020/