Tag: review

Investigating the enterovirus theory of disease etiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome

Abstract:

Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is a complex, multi-system disease whose etiological basis has not been established. Over the years, several pathogenic agents have been implicated with no one pathogen being conclusively identified as responsible for induction of a large number of cases. Enteroviruses (EVs) as a cause of ME/CFS have sometimes been proposed, as they are known agents of acute respiratory and gastrointestinal infections that may persist in chronic infection sites, including the central nervous system, muscle, and heart, potentially resulting in chronic conditions that have symptom constellations like those of ME/CFS.

To gain insight into the association between EVs and ME/CFS, I conducted a comprehensive review of EV studies in ME/CFS and followed this with 1) a broad serological survey of ME/CFS antibody levels to 122 pathogenic antigens and 2) designed and conducted EV-specific targeted RNA sequencing.

A review of prior ME/CFS investigations in ME/CFS revealed a strong prevalence of chronic EV infections across ME/CFS cohorts. The broad survey of anti-pathogen antibody levels in ME/CFS cases did not implicate any one pathogen as a causative factor in ME/CFS, nor do they rule out common pathogens that frequently infect the US population. However, the results did reveal sex-based differences in steady-state humoral immunity, both within the ME/CFS cohort and when compared to trends seen in the healthy control cohort.

Furthermore, I find that our EV-specific probe set allows efficient viral detection when as few as 10 molecules are present in 1ml of blood. However, whether the technology is employed directly on patient samples or following attempts at in vitro biological amplification, EVs were undetected in both ME/CFS and healthy control samples despite all approaches that were pursued.

This work establishes a thorough understanding of the current EV-ME/CFS related literature while simultaneously providing an acutely sensitive and comprehensive approach that will be useful in the future for screening biopsy or cadaver samples from any individuals suspected of having a chronic EV infection.

Source: O’Neal, Adam James. Investigating the enterovirus theory of disease etiology in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Dissertation, Cornell. https://ecommons.cornell.edu/handle/1813/112023 (Full text will be made available)

The autoimmune aetiology of unexplained chronic pain

Abstract:

Chronic pain is the leading cause of life years lived with disability worldwide. The aetiology of most chronic pain conditions has remained poorly understood and there is a dearth of effective therapies. The WHO ICD-11 has categorised unexplained chronic pain states as ‘chronic primary pains’ (CPP), which are further defined by their association with significant distress and/or dysfunction. The new mechanistic term, ‘nociplasticic pain’ has been developed to illustrate their presumed generation by a structurally intact, but abnormally functioning nociceptive system.

Recently, researchers have unravelled the surprising, ubiquitous presence of pain-sensitising autoantibodies in four investigated CPP indicating autoimmune causation. In persistent complex regional pain syndrome, fibromyalgia syndrome, chronic post-traumatic limb pain, and non-inflammatory joint pain associated with rheumatoid arthritis, passive transfer experiments have shown that either IgG or IgM antibodies from patient-donors cause symptoms upon injection to rodents that closely resemble those of the clinical disorders. Targets of antibody-binding and downstream effects vary between conditions, and more research is needed to elucidate the molecular and cellular details.

The central nervous system appears largely unaffected by antibody binding, suggesting that the clinically evident CNS symptoms associated with CPP might arise downstream of peripheral processes. In this narrative review pertinent findings are described, and it is suggested that additional symptom-based disorders might be examined for the contribution of antibody-mediated autoimmune mechanisms.

Source: Goebel A, Andersson D, Helyes Z, Clark JD, Dulake D, Svensson C. The autoimmune aetiology of unexplained chronic pain. Autoimmun Rev. 2022 Mar;21(3):103015. doi: 10.1016/j.autrev.2021.103015. Epub 2021 Dec 10. PMID: 34902604. https://www.sciencedirect.com/science/article/abs/pii/S1568997221002974 (Full text)

Long-COVID Syndrome and the Cardiovascular System: A Review of Neurocardiologic Effects on Multiple Systems

Abstract:

Purpose of review: Long-COVID syndrome is a multi-organ disorder that persists beyond 12 weeks post-acute SARS-CoV-2 infection (COVID-19). Here, we provide a definition for this syndrome and discuss neuro-cardiology involvement due to the effects of (1) angiotensin-converting enzyme 2 receptors (the entry points for the virus), (2) inflammation, and (3) oxidative stress (the resultant effects of the virus).

Recent findings: These effects may produce a spectrum of cardio-neuro effects (e.g., myocardial injury, primary arrhythmia, and cardiac symptoms due to autonomic dysfunction) which may affect all systems of the body. We discuss the symptoms and suggest therapies that target the underlying autonomic dysfunction to relieve the symptoms rather than merely treating symptoms. In addition to treating the autonomic dysfunction, the therapy also treats chronic inflammation and oxidative stress. Together with a full noninvasive cardiac workup, a full assessment of the autonomic nervous system, specifying parasympathetic and sympathetic (P&S) activity, both at rest and in response to challenges, is recommended. Cardiac symptoms must be treated directly. Cardiac treatment is often facilitated by treating the P&S dysfunction. Cardiac symptoms of dyspnea, chest pain, and palpitations, for example, need to be assessed objectively to differentiate cardiac from neural (autonomic) etiology. Long-term myocardial injury commonly involves P&S dysfunction. P&S assessment usually connects symptoms of Long-COVID to the documented autonomic dysfunction(s).

Source: DePace NL, Colombo J. Long-COVID Syndrome and the Cardiovascular System: A Review of Neurocardiologic Effects on Multiple Systems. Curr Cardiol Rep. 2022 Sep 30:1–16. doi: 10.1007/s11886-022-01786-2. Epub ahead of print. PMID: 36178611; PMCID: PMC9524329.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9524329/ (Full text)

The significance of oxidative stress in the pathophysiology of Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

Long COVID is now well accepted as an ongoing post-viral syndrome resulting from infection of a single virus, the pandemic SARS-CoV-2. It mirrors the post-viral fatigue syndrome, Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome, a global debilitating illness arising mainly from sporadic geographically-specific viral outbreaks, and from community endemic infections, but also from other stressors. Core symptoms of both syndromes are post-exertional malaise (a worsening of symptoms following mental or physical activity), pervasive fatigue, cognitive dysfunction (brain fog), and sleep disturbance. Long COVID patients frequently also suffer from shortness of breath, relating to the lung involvement of the SARS-CoV-2 virus.

There is no universally accepted pathophysiology, or recognized biomarkers yet for Long COVID or indeed for Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Clinical case definitions with very similar characteristics for each have been defined. Chronic inflammation, immune dysfunction, and disrupted energy production in the peripheral system has been confirmed in Long COVID and has been well documented in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome.

Neuroinflammation occurs in the brain in Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome as shown from a small number of positron emission tomography and magnetic resonance spectroscopy studies, and has now been demonstrated for Long COVID. Oxidative stress, an increase in reactive oxygen and reactive nitrogen species, and free radicals, has long been suggested as a potential cause for many of the symptoms seen in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, resulting from both activation of the brain’s immune system and dysregulation of mitochondrial function throughout the body. The brain as a high producer of energy may be particularly susceptible to oxidative stress. It has been shown in peripheral immune cells that the balanced production of proteins involved in regulation of the reactive oxygen species in mitochondria is disturbed in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. Fluctuations in the chronic low level neuroinflammation during the ongoing course of Long COVID as well as Myalgic Encephalomyelitis/Chronic Fatigue Syndrome have been proposed to cause the characteristic severe relapses in patients.

This review explores oxidative stress as a likely significant contributor to the pathophysiology of Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome, and the mechanisms by which oxidative stress could cause the symptoms seen in both syndromes. Treatments that could mitigate oxidative stress and thereby lessen the debilitating symptoms to improve the life of patients are discussed.

Source: WALKER, Max Oliver Mackay et al. The significance of oxidative stress in the pathophysiology of Long COVID and Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS). Medical Research Archives, [S.l.], v. 10, n. 9, sep. 2022. ISSN 2375-1924. Available at: <https://esmed.org/MRA/mra/article/view/3050>. Date accessed: 09 oct. 2022. doi: https://doi.org/10.18103/mra.v10i9.3050.

Lactoferrin as Possible Treatment for Chronic Gastrointestinal Symptoms in Children with Long COVID: Case Series and Literature Review

Abstract:

Long COVID is an emergent, heterogeneous, and multisystemic condition with an increasingly important impact also on the pediatric population. Among long COVID symptoms, patients can experience chronic gastrointestinal symptoms such as abdominal pain, constipation, diarrhea, vomiting, nausea, and dysphagia.
Although there is no standard, agreed, and optimal diagnostic approach or treatment of long COVID in children, recently compounds containing multiple micronutrients and lactoferrin have been proposed as a possible treatment strategy, due to the long-standing experience gained from other gastrointestinal conditions. In particular, lactoferrin is a pleiotropic glycoprotein with antioxidant, anti-inflammatory, antithrombotic, and immunomodulatory activities. Moreover, it seems to have several physiological functions to protect the gastrointestinal tract.
In this regard, we described the resolution of symptoms after the start of therapy with high doses of oral lactoferrin in two patients referred to our post-COVID pediatric unit due to chronic gastrointestinal symptoms after SARS-CoV-2 infection.
Source: Morello R, De Rose C, Cardinali S, Valentini P, Buonsenso D. Lactoferrin as Possible Treatment for Chronic Gastrointestinal Symptoms in Children with Long COVID: Case Series and Literature Review. Children. 2022; 9(10):1446. https://doi.org/10.3390/children9101446 (Full text)

Polyphenols as possible alternative agents in chronic fatigue: a review

Abstract:

Chronic fatigue syndrome (CFS) is a pathological state of extreme tiredness that lasts more than six months and may possess an impact on the social, emotional, or occupational functioning of an individual. CFS is characterized by profound disabling fatigue associated with infectious, rheumatological, and neurological symptoms.

The current pharmacological treatment for CFS does not offer a complete cure for the disease, and none of the available treatments show promising results.

The exact mechanism of the pathogenesis of the disease is still unknown, with current suggestions indicating the overlapping roles of the immune system, central nervous system, and neuroendocrine system.

However, the pathological mechanism revolves around inflammatory and oxidative stress markers.

Polyphenols are the most abundant secondary metabolites of plant origin, with potent antioxidant and anti-inflammatory effects, and can exert protective activity against a whole range of disorders.

The current review is aimed at highlighting the emerging role of polyphenols in CFS from both preclinical and clinical studies. Numerous agents of this class have shown promising results in different in vitro and in vivo models of chronic fatigue/CFS, predominantly by counteracting oxidative stress and the inflammatory cascade.

The clinical data in this regard is still very limited and needs expanding through randomized, placebo-controlled studies to draw final conclusions on whether polyphenols may be a class of clinically effective nutraceuticals in patients with CFS.

Source: Ullah, H., Khan, A., Riccioni, C. et al. Polyphenols as possible alternative agents in chronic fatigue: a review. Phytochem Rev (2022). https://doi.org/10.1007/s11101-022-09838-9 (Full text)

Post-acute COVID syndrome (long COVID): What should radiographers know and the potential impact for imaging services

Abstract:

Objectives: The COVID-19 pandemic caused an unprecedented health crisis resulting in over 6 million deaths worldwide, a figure, which continues to grow. In addition to the excess mortality, there are individuals who recovered from the acute stages, but suffered long-term changes in their health post COVID-19, commonly referred to as long COVID. It is estimated there are currently 1.8 million long COVID sufferers by May 2022 in the UK alone. The aim of this narrative literature review is to explore the signs, symptoms and diagnosis of long COVID and the potential impact on imaging services.

Key findings: Long COVID is estimated to occur in 9.5% of those with two doses of vaccination and 14.6% if those with a single dose or no vaccination. Long COVID is defined by ongoing symptoms lasting for 12 or more weeks post acute infection. Symptoms are associated with reductions in the quality of daily life and may involve multisystem manifestations or present as a single symptom.

Conclusion: The full impact of long COVID on imaging services is yet to be realised, but there is likely to be significant increased demand for imaging, particularly in CT for the assessment of lung disease. Educators will need to include aspects related to long COVID pathophysiology and imaging presentations in curricula, underpinned by the rapidly evolving evidence base.

Implications for practice: Symptoms relating to long COVID are likely to become a common reason for imaging, with a particular burden on Computed Tomography services. Planning, education and updating protocols in line with a rapidly emerging evidence base is going to be essential.

Source: Alghamdi F, Owen R, Ashton REM, Obotiba AD, Meertens RM, Hyde E, Faghy MA, Knapp KM, Rogers P, Strain WD. Post-acute COVID syndrome (long COVID): What should radiographers know and the potential impact for imaging services. Radiography (Lond). 2022 Sep 12:S1078-8174(22)00119-5. doi: 10.1016/j.radi.2022.08.009. Epub ahead of print. PMID: 36109264; PMCID: PMC9468096. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9468096/ (Full text)

What we already know about the Post-COVID-19 Syndrome: A narrative review

Abstract:

As an increasingly number of patients recover from the acute COVID-19 disease, it has been observed that many face long lasting symptoms, referred as the Post-COVID-19 Syndrome. This article covers the most common signs and symptoms of this syndrome, its general aspects, and important complementary exams related to the disease. The manuscript is a narrative review, gathering new evidence published about the topic.

The most common symptoms of the Post-COVID-19 Syndrome are chronic fatigue, breathlessness, depression or anxiety, pain, cough and alopecia, and many of them are still present 6 months after hospital discharge from the acute disease, depending on the gravity of the illness. It is important for patients to maintain medical follow-up to access severity of the symptoms and choose whether further investigation is necessary. There are some treatments available to some minimize the long-lasting burden of the syndrome, and the physician should access the need for treatment with the patient.

As a new disease, there is a lot of new evidence being produced rapidly, but no up-to-date protocol has already been published. Even with the vaccinations campaigns, the burden of the pandemic is yet out of sight, as it still killing thousands daily, and those who have recovered from the acute COVID-19 illness can present chronic symptoms. Therefore, we recommend health professionals to continuously up-to-date themselves, as new information is added to make better clinical decisions.

Source: RESENDE, M. D. de .; RESENDE, G. D. de .; RIQUIERI, L. N. .; SANTOS, A. F. A. dos .; CASTRO, A. C. A. de .; ROCHA, M. da C. . What we already know about the Post-COVID-19 Syndrome: A narrative review. Research, Society and Development, [S. l.], v. 11, n. 12, p. e108111234143, 2022. DOI: 10.33448/rsd-v11i12.34143. https://rsdjournal.org/index.php/rsd/article/view/34143

Current knowledge about Chronic fatigue syndrome / myalgic encephalomyelitis (CFS/ME) causes – summary

Abstract:

Chronic Fatigue Syndrome (CFE) is a severe and disabling disease whose etiology has not yet been elucidated. This implies the lack of a specific biomarker for the diagnosis of PE, and no causal treatment.

There are a number of diagnostic criteria that facilitate the diagnosis of PE, but it is still a diagnosis with exclusion. This chapter reviews the scientific literature systematically, summarizing the available knowledge about the probable etiology of Chronic Fatigue Syndrome.

The current topic of the influence of SARS-Cov-2 virus infection on the development of symptoms of IPC was also taken into account in particular.

A clear explanation of the etiology of PE is necessary for the further development of scientific knowledge about the Chronic Fatigue Syndrome.

Source: PRYLIŃSKA-JAŚKOWIAK, Monika & KOŻUCHOWSKI, Marcin. Current knowledge about Chronic fatigue syndrome / myalgic encephalomyelitis (CFS/ME) causes – summary. Journal of Education, Health and Sport [online]. 13 September 2022, T. 12, nr 9, s. 712–719. [accessed 26.9.2022]. DOI 10.12775/JEHS.2022.12.09.084.  https://apcz.umk.pl/JEHS/article/view/39954 https://apcz.umk.pl/JEHS/article/view/39954/33214 (Full text)