Tag: inflammation

Low omega-3 index and polyunsaturated fatty acid status in patients with chronic fatigue syndrome/myalgic encephalomyelitis

Abstract:

BACKGROUND: Several studies have suggested that low levels of omega-3 fatty acids (n-3 PUFAs) including eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are associated with cardiovascular risk, major depression, sleep problems, inflammation and other health-related issues. So far, however, erythrocyte PUFA status in Chronic Fatigue Syndrome/Myalgic Encephalomyelitis (CFS/ME) has not been established. This study aimed to determine whether n-3 PUFA content and omega-3 index are associated with measures in CFS/ME patients.

PATIENTS AND METHODS: PUFA levels and omega-3 index were measured in 31 Spanish CFS/ME patients using the HS-Omega-3 Index method. Demographic and clinical characteristics and self-reported outcome measures were also recorded.

RESULTS: A low mean omega-3 index (5.75%) was observed in 92.6% of the sample. Omega-3 index was inversely correlated with the AA/EPA ratio (p = 0.00002) and the BMI (p = 0.0106). In contrast, the AA/EPA ratio was positively associated with the BMI (p = 0.0038). No association for FIS-40 and PSQI measures was found (p > 0.05).

CONCLUSION: The low omega-3 index found in our CFS/ME patients may indicate increased risks for cardiovascular health, which should be further investigated. A low omega-3 index also suggests a pro-inflammatory state in these patients. Attempts should be made to increase the omega-3 index in CFS/ME patients, based on intervention trials assessing a potential therapeutic value.

Source: Castro-Marrero J, Zaragozá MC, Domingo JC, Martinez-Martinez A, Alegre J, von Schacky C. Low omega-3 index and polyunsaturated fatty acid status in patients with chronic fatigue syndrome/myalgic encephalomyelitis. Prostaglandins Leukot Essent Fatty Acids. 2018 Dec;139:20-24. doi: 10.1016/j.plefa.2018.11.006. Epub 2018 Nov 9. https://www.ncbi.nlm.nih.gov/pubmed/30471769

Markers of fungal translocation are elevated during post-acute sequelae of SARS-CoV-2 and induce NF-κB signaling

Abstract:

Long COVID, a type of Post-Acute Sequelae of SARS-CoV-2 (PASC), has been associated with sustained elevated levels of immune activation and inflammation. However, the mechanisms that drive this inflammation remain unknown. Inflammation during acute Coronavirus Disease 2019 could be exacerbated by microbial translocation (from gut and/or lung) to blood. Whether microbial translocation contributes to inflammation during PASC is unknown.

We did not observe a significant elevation in plasma markers of bacterial translocation during PASC. However, we observed higher levels of fungal translocation – measured as β-glucan, a fungal cell wall polysaccharide – in the plasma of individuals experiencing PASC compared to those without PASC or SARS-CoV-2 negative controls. The higher β-glucan correlated with higher inflammation and elevated levels of host metabolites involved in activating N-Methyl-D-aspartate receptors (such as metabolites within the tryptophan catabolism pathway) with established neuro-toxic properties. Mechanistically, β-glucan can directly induce inflammation by binding to myeloid cells (via Dectin-1) and activating Syk/NF-κB signaling.

Using a Dectin-1/NF-κB reporter model, we found that plasma from individuals experiencing PASC induced higher NF-κB signaling compared to plasma from negative controls. This higher NF-κB signaling was abrogated by Piceatannol (Syk inhibitor). These data suggest a potential targetable mechanism linking fungal translocation and inflammation during PASC.

Source: Giron LB, Peluso MJ, Ding J, Kenny G, Zilberstein NF, Koshy J, Hong KY, Rasmussen H, Miller GE, Bishehsari F, Balk RA, Moy JN, Hoh R, Lu S, Goldman AR, Tang HY, Yee BC, Chenna A, Winslow JW, Petropoulos CJ, Kelly JD, Wasse H, Martin JN, Liu Q, Keshavarzian A, Landay A, Deeks SG, Henrich TJ, Abdel-Mohsen M. Markers of fungal translocation are elevated during post-acute sequelae of SARS-CoV-2 and induce NF-κB signaling. JCI Insight. 2022 Jun 21:e160989. doi: 10.1172/jci.insight.160989. Epub ahead of print. PMID: 35727635. https://pubmed.ncbi.nlm.nih.gov/35727635/

Inflammation during early post-acute COVID-19 is associated with reduced exercise capacity and Long COVID symptoms after 1 year

Abstract:

Background: Mechanisms underlying persistent cardiopulmonary symptoms following SARS-CoV-2 infection (post-acute sequelae of COVID-19 “PASC” or “Long COVID”) remain unclear. The purpose of this study was to elucidate the pathophysiology of cardiopulmonary PASC using multimodality cardiovascular imaging including cardiopulmonary exercise testing (CPET), cardiac magnetic resonance imaging (CMR) and ambulatory rhythm monitoring.

Methods: We performed CMR, CPET, and ambulatory rhythm monitoring among adults > 1 year after PCR-confirmed SARS-CoV-2 infection in the UCSF Long-Term Impact of Infection with Novel Coronavirus cohort (LIINC; NCT04362150 ) and correlated findings with previously measured biomarkers. We used logistic regression to estimate associations with PASC symptoms (dyspnea, chest pain, palpitations, and fatigue) adjusted for confounders and linear regression to estimate differences between those with and without symptoms adjusted for confounders.

Results: Out of 120 participants in the cohort, 46 participants (unselected for symptom status) had at least one advanced cardiac test performed at median 17 months following initial SARS-CoV-2 infection. Median age was 52 (IQR 42-61), 18 (39%) were female, and 6 (13%) were hospitalized for severe acute infection. On CMR (n=39), higher extracellular volume was associated with symptoms, but no evidence of late-gadolinium enhancement or differences in T1 or T2 mapping were demonstrated. We did not find arrhythmias on ambulatory monitoring. In contrast, on CPET (n=39), 13/23 (57%) with cardiopulmonary symptoms or fatigue had reduced exercise capacity (peak VO 2 <85% predicted) compared to 2/16 (13%) without symptoms (p=0.008). The adjusted difference in peak VO 2 was 5.9 ml/kg/min lower (-9.6 to -2.3; p=0.002) or -21% predicted (-35 to -7; p=0.006) among those with symptoms. Chronotropic incompetence was the primary abnormality among 9/15 (60%) with reduced peak VO 2 . Adjusted heart rate reserve <80% was associated with reduced exercise capacity (OR 15.6, 95%CI 1.30-187; p=0.03). Inflammatory markers (hsCRP, IL-6, TNF-α) and SARS-CoV-2 antibody levels measured early in PASC were negatively correlated with peak VO 2 more than 1 year later.

Conclusions: Cardiopulmonary symptoms and elevated inflammatory markers present early in PASC are associated with objectively reduced exercise capacity measured on cardiopulmonary exercise testing more than 1 year following COVID-19. Chronotropic incompetence may explain reduced exercise capacity among some individuals with PASC.

Clinical perspective: What is New? Elevated inflammatory markers in early post-acute COVID-19 are associated with reduced exercise capacity more than 1 year later. Impaired chronotropic response to exercise is associated with reduced exercise capacity and cardiopulmonary symptoms more than 1 year after SARS-CoV-2 infection. Findings on ambulatory rhythm monitoring point to perturbed autonomic function, while cardiac MRI findings argue against myocardial dysfunction and myocarditis.

Clinical implications: Cardiopulmonary testing to identify etiologies of persistent symptoms in post-acute sequalae of COVID-19 or “Long COVID” should be performed in a manner that allows for assessment of heart rate response to exercise. Therapeutic trials of anti-inflammatory and exercise strategies in PASC are urgently needed and should include assessment of symptoms and objective testing with cardiopulmonary exercise testing.

Source: Durstenfeld MS, Peluso MJ, Kaveti P, Hill C, Li D, Sander E, Swaminathan S, Arechiga VM, Sun K, Ma Y, Zepeda V, Lu S, Goldberg SA, Hoh R, Chenna A, Yee BC, Winslow JW, Petropoulos CJ, Win S, Kelly JD, Glidden DV, Henrich TJ, Martin JN, Lee YJ, Aras MA, Long CS, Grandis DJ, Deeks SG, Hsue PY. Inflammation during early post-acute COVID-19 is associated with reduced exercise capacity and Long COVID symptoms after 1 year. medRxiv [Preprint]. 2022 Jun 1:2022.05.17.22275235. doi: 10.1101/2022.05.17.22275235. PMID: 35677073; PMCID: PMC9176659. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9176659/ (Full text)

SARS-CoV-2-specific T cells associate with inflammation and reduced lung function in pulmonary post-acute sequalae of SARS-CoV-2

Abstract:

As of January 2022, at least 60 million individuals are estimated to develop post-acute sequelae of SARS-CoV-2 (PASC) after infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). While elevated levels of SARS-CoV-2-specific T cells have been observed in non-specific PASC, little is known about their impact on pulmonary function which is compromised in the majority of these individuals. This study compares frequencies of SARS-CoV-2-specific T cells and inflammatory markers with lung function in participants with pulmonary PASC and resolved COVID-19 (RC).

Compared to RC, participants with respiratory PASC had between 6- and 105-fold higher frequencies of IFN-γ- and TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells in peripheral blood, and elevated levels of plasma CRP and IL-6. Importantly, in PASC participants the frequency of TNF-α-producing SARS-CoV-2-specific CD4+ and CD8+ T cells, which exhibited the highest levels of Ki67 indicating they were activity dividing, correlated positively with plasma IL-6 and negatively with measures of lung function, including forced expiratory volume in one second (FEV1), while increased frequencies of IFN-γ-producing SARS-CoV-2-specific T cells associated with prolonged dyspnea.

Statistical analyses stratified by age, number of comorbidities and hospitalization status demonstrated that none of these factors affect differences in the frequency of SARS-CoV-2 T cells and plasma IL-6 levels measured between PASC and RC cohorts. Taken together, these findings demonstrate elevated frequencies of SARS-CoV-2-specific T cells in individuals with pulmonary PASC are associated with increased systemic inflammation and decreased lung function, suggesting that SARS-CoV-2-specific T cells contribute to lingering pulmonary symptoms. These findings also provide mechanistic insight on the pathophysiology of PASC that can inform development of potential treatments to reduce symptom burden.

Source: Katherine M. Littlefield,Renée O. Watson,Jennifer M. Schneider,Charles P. Neff,Eiko Yamada,Min Zhang,Thomas B. Campbell,Michael T. Falta,Sarah E. Jolley,Andrew P. Fontenot,Brent E. Palmer. SARS-CoV-2-specific T cells associate with inflammation and reduced lung function in pulmonary post-acute sequalae of SARS-CoV-2. PLOS Pathogens. Published: May 26, 2022 https://doi.org/10.1371/journal.ppat.1010359  (Full text)

The occurrence of hyperactivated platelets and fibrinaloid microclots in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS)

Abstract:

We have previously demonstrated that platelet poor plasma (PPP) obtained from patients with LongCovid/Post-Acute Sequelae of COVID-19 (PASC) is characterized by a hypercoagulable state reflected in hyperactivated platelets and the presence of considerable numbers of fibrin(ogen) amyloid microclots or fibrinaloid microclots. Due to substantial overlap in symptoms and aetiology between PASC and ME/CFS, we investigated whether coagulopathies, platelet hyperactivation and/or fibrin amyloid formation differed between individuals exhibiting ME/CFS and gender- and age-matched healthy controls.

ME/CFS patients were statistically far more hypercoagulable as judged by thromboelastography of both whole blood and platelet-poor plasma. The area of plasma images containing fibrinaloid microclots was commonly more than 10-fold greater in untreated platelet-poor plasma from individuals with ME/CFS than in that of healthy controls. A similar difference was found when the plasma samples were treated with thrombin. Using fluorescently labelled PAC-1, which recognizes glycoprotein IIb/IIIa, and CD62P, which binds P-selectin, we observed massive hyperactivation and spreading of platelets in samples from individuals with ME/CFS. Using a quantitative scoring system, this was found to have a score of 2.72 ± 1.24 vs 1.00 (activation with pseudopodia formation) for healthy controls.

We conclude that ME/CFS is accompanied by substantial and measurable changes in coagulability, platelet hyperactivation, and fibrinaloid microclot formation. However, fibrinaloid microclot load was not as prevalent as was previously noted in PASC. Fibrinaloid microclots, in particular can provide a ready explanation, via (temporary) blockage of microcapillaries and hence ischaemia, for many of the symptoms, such as fatigue, seen in patients with ME/CFS. The discovery of these biomarkers pointing to significant and systemic endothelial inflammation, represents an important development in ME/CFS research. It also points at novel treatment strategies using known drugs and/or nutraceuticals that target systemic vascular pathology and endothelial inflammation.

Source: Massimo Nunes, Arneaux Kruger, Amy Proal et al. The occurrence of hyperactivated platelets and fibrinaloid microclots in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS), 08 June 2022, PREPRINT (Version 1) available at Research Square https://doi.org/10.21203/rs.3.rs-1727226/v1 (Full text)

Cytokine network analysis in a community-based pediatric sample of patients with myalgic encephalomyelitis/chronic fatigue syndrome

Abstract:

Objectives: Studies have demonstrated immune dysfunction in adolescents with Myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS); however, evidence is varied. The current study used network analysis to examine relationships between cytokines among a sample of pediatric participants with ME/CFS.

Methods: 10,119 youth aged 5-17 in the Chicagoland area were screened for ME/CFS; 111 subjects and controls were brought in for a physician examination and completed a blood draw. Youth were classified as controls (Cs, N = 43), ME/CFS (N = 23) or severe (S-ME/CFS, N = 45). Patterns of plasma cytokine networks were analyzed.

Results: All participant groups displayed a primary network of interconnected cytokines. In the ME/CFS group, inflammatory cytokines IL-12p70, IL-17A, and IFN-γ were connected and included in the primary membership, suggesting activation of inflammatory mechanisms. The S-ME/CFS group demonstrated a strong relationship between IL-17A and IL-23, a connection associated with chronic inflammation. The relationships of IL-6 and IL-8 in ME/CFS and S-ME/CFS participants also differed from Cs. Together, these results indicate pro-inflammatory responses in our illness populations.

Discussion: Our data imply biological differences between our three participant groups, with ME/CFS and S-ME/CFS participants demonstrating an inflammatory profile. Examining co-expression of cytokines may aid in the identification of a biomarker for pediatric ME/CFS.

Source: Jason LA, Gaglio CL, Furst J, Islam M, Sorenson M, Conroy KE, Katz BZ. Cytokine network analysis in a community-based pediatric sample of patients with myalgic encephalomyelitis/chronic fatigue syndrome. Chronic Illn. 2022 May 16:17423953221101606. doi: 10.1177/17423953221101606. Epub ahead of print. PMID: 35570777.  https://pubmed.ncbi.nlm.nih.gov/35570777/

Long COVID: systemic inflammation and obesity as therapeutic targets

Management of the post-COVID-19 condition—often referred to as long COVID—is a challenge for health-care professionals because of the heterogeneity and complexity of its clinical manifestations and the probable need for multidisciplinary management approaches. Identification and understanding of modifiable determinants associated with manifestations of long COVID would help in the adaptation of treatment pathways for particular phenotypes. In The Lancet Respiratory Medicine, the PHOSP-COVID Collaborative Group report the latest results from the UK-based, multicentre, prospective Post-hospitalisation COVID-19 (PHOSP-COVID) study, in which the investigators identified systemic inflammation and obesity as factors that might be associated with long COVID, representing potentially treatable traits in people with more severe post-COVID-19 symptoms.

In the current report, the PHOSP-COVID Collaborative Group found increased levels of several biomarkers related to systemic inflammation and lung damage in individuals with more severe physical and mental health impairments 1 year after hospital discharge. The presence of increased levels of systemic inflammatory biomarkers (eg, cytokines) in individuals with severe acute COVID-19 has been reported previously. Moreover, the use of anti-inflammatory agents such as corticosteroids or interleukin-6 (IL-6)-blocking agents has been found to be associated with positive outcomes in patients hospitalised with acute COVID-19.

Read the rest of this article HERE.

Source: Florencio LL, Fernández-de-Las-Peñas C. Long COVID: systemic inflammation and obesity as therapeutic targets. Lancet Respir Med. 2022 Apr 22:S2213-2600(22)00159-X. doi: 10.1016/S2213-2600(22)00159-X. Epub ahead of print. PMID: 35472305; PMCID: PMC9034853. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9034853/ (Full text)

Post-acute COVID-19 syndrome presented as a cerebral and systemic vasculitis: a case report

To the Editor,

Post-acute Coronavirus Disease of 2019 (COVID-19) syndrome is defined as the appearance of symptoms or an organ dysfunction, which occurs at least 4 weeks after the first COVID-19 manifestations and cannot be explained by any alternative diagnosis []. Neurological complications are also well recognized, and include acute cerebrovascular events, encephalopathy, meningoencephalitis, Guillain–Barre syndrome, demyelination, dementia, parkinsonism, and others []. On the other hand, cerebral vasculitis is one of the causes which can lead to brain damage related to COVID-19 infection []. We present a 69-year-old male with systemic vasculitis and central nervous system (CNS) involvement as a manifestation of post-acute COVID-19 syndrome.

Read the rest of this article HERE.

Source: Ivanovic, Jovana et al. “Post-acute COVID-19 syndrome presented as a cerebral and systemic vasculitis: a case report.” Acta neurologica Belgica, 1–3. 13 Mar. 2022, doi:10.1007/s13760-022-01923-2 https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8918071/ (Full text)

Post-COVID-19 syndrome, low-grade inflammation and inflammatory markers: a cross-sectional study

Abstract:

Objective: Post-COVID syndrome (PCS) is a poorly known entity. An underlying chronic, low-grade inflammation (LGI) has been theorized as a pathophysiological mechanism. Available data on biomarkers in PCS show conflicting results. Our aim was to know whether subjects with PCS present higher levels of inflammatory markers, after a mild COVID-19.

Methods: Analytical cross-sectional study. Cases of mild COVID-19 in a community setting were included. We collected epidemiological data (age, sex, BMI, smoking, comorbidities), variables of the acute COVID-19 (duration, symptoms), and data at 3 months after the acute phase (symptoms and laboratory test). Serum C-reactive protein (CRP), neutrophil and lymphocyte counts, neutrophil/lymphocyte ratio (NLR), lactate dehydrogenase, ferritin, fibrinogen, and D-dimer levels were analysed. LGI was defined as CRP >0.3 and <1.0 mg/dL. A subject was classified as PCS + if presented signs and symptoms >12 weeks after an infection consistent with COVID-19. Five composite indices (C1-C5) were developed, combining the upper ranges of biomarkers distributions. Multivariate analyses were performed.

Results: We analysed 121 mild COVID-19 cases (mean age =45.7 years, 56.2% women). Among the acute symptoms, women presented a higher frequency of fatigue (54.4% vs 30.2%;p = 0.008). PCS affected 35.8% of women and 20.8% of men (p = 0.07), and the most reported symptoms were fatigue (42.8%), anosmia (40%), ageusia (22.8%), dyspnea (17.1%) and myalgia (11.4%). Neutrophil count, NLR, CRP and fibrinogen showed the best correlations with PCS, and were selected to develop the indices. In women PCS+, C1, C3 and C4 indices were more frequently met, while in men PCS+, C2, C5 and CRP in range of LGI. Anosmia, ageusia and fatigue were related to higher neutrophil counts, with sex differences. Fibrinogen levels were higher in persistent myalgia (510 ± 82 mg/dL vs 394 ± 87;p = 0.013). In multivariable analysis, a woman with a neutrophil count above the median, or with fibrinogen level or NLR in the highest tertile, had a 4- to 5-fold increased risk of prevalent PCS. A man with CRP in range of LGI, or fibrinogen level or a neutrophil count in the highest tertile, had a 10- to 17-fold increased risk of prevalent PCS.

Conclusions: The data obtained in the present cross-sectional study seems to demonstrate a consistent association between PCS and upper ranges of the neutrophil count, NLR, fibrinogen, and CRP in the LGI range. Furthermore, composite indices appear useful in detecting relationships between slight elevations of biomarkers and PCS, and our study identifies relevant sex differences in symptoms and markers regarding the PCS.

Source: Maamar M, Artime A, Pariente E, Fierro P, Ruiz Y, Gutiérrez S, Tobalina M, Díaz-Salazar S, Ramos C, Olmos JM, Hernández JL. Post-COVID-19 syndrome, low-grade inflammation and inflammatory markers: a cross-sectional study. Curr Med Res Opin. 2022 Feb 15:1-26. doi: 10.1080/03007995.2022.2042991. Epub ahead of print. PMID: 35166141.  https://pubmed.ncbi.nlm.nih.gov/35166141/

Letter: Could endothelial dysfunction and vascular damage contribute to pain, inflammation and post-exertional malaise in individuals with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)?

To the Editor,

In their hypothesis paper, Wirth, Scheibenbogen, and Paul describe how endothelial dysfunction could produce a wide range of neurological symptoms in people with ME/CFS [1]. As they and others work to refine their understanding of ME/CFS and the related Long COVID syndrome, I would encourage consideration of the possibility that endothelial dysfunction and vascular damage could also explain other symptoms, including widespread pain and inflammation and post-exertional malaise.

For the past four years, my wife and I have been caregivers for our teenage daughter, who has ME/CFS, hypermobile Ehlers-Danlos syndrome, craniocervical instability, Chiari malformation and several other comorbid conditions. Through observation and trial and error, I have developed a number of hypotheses on these matters that I offer here in the hope they might prompt formal research into how to effectively treat these conditions [2].

Widespread pain and inflammation

Discussion of endothelial dysfunction and vascular damage in ME/CFS and Long COVID generally focuses on how leakages from dysfunctional blood vessels lead to reduced blood flow, which has many consequences, including reduced oxygenation of muscles and reduced cerebral brain flow. As researchers study this phenomenon, I would encourage consideration of the additional possibility that the leaking fluid causes independent damage. Lipedema researchers have found that leakages from microangiopathic blood vessels cause an excess of interstitial fluid that stimulates the formation of subcutaneous adipose tissue [3], which generates hypoxic conditions and becomes fibrotic, contributing to pain and inflammation [4].

I hypothesize that a similar process happens when fluid leaks from faulty blood vessels in ME/CFS, possibly exacerbated by endothelial dysfunction in lymphatic vessels that inhibit the fluid’s removal, causing widespread pain and inflammation. This mechanism appears most pronounced among people with hypermobility or other connective tissue disorders, a common trait among people with both ME/CFS and lipedema.

My daughter experiences pain from fibrotic adipose tissue as well as what appears to be nerve compression from accumulated interstitial / lymphatic fluid. Manual lymphatic drainage, the squeezing of affected tissue, and the manual break-up of fibrotic adipose tissue have helped to ameliorate these symptoms.

In my daughter, I have also observed impaired drainage of fluid from the glymphatic system, both at the cribriform plate and down her spine. Could this be related to damaged lymphatic vessels or blockages from fibrotic adipose tissue?

Post-exertional malaise

Like many people with moderate or severe ME/CFS, my daughter struggles to recover from even small amounts of physical exertion. In addition to mitigating her pain, manual lymphatic drainage and the squeezing of affected tissue greatly accelerates this recovery process. We have observed a direct dose–response relationship: the more exercise, the more fluid is present in her tissues, and the more manual draining / squeezing is necessary for her to recover.

Based on this experience, I hypothesize that excess interstitial fluid resulting from dysfunctional blood and lymphatic vessels contributes to the experience of post-exertional malaise, with fluid literally drowning affected tissue, leading to hypoxic conditions and inflammation. Possible explanations for the increased interstitial fluid are increases in blood pressure during physical exertion, hypermobile joints going out of place, prompting localized increases in interstitial fluid, and increases in cortisol that generate an increase in fluid and blood volume. Increases in fluid leakage due to elevated cortisol levels may also explain why some people with ME/CFS feel worse when stressed or anxious. The role of cortisol (or another mediator with fluid retaining properties) may explain why cognitive exertion can also generate post-exertional malaise. When present, elevated estrogen levels may exacerbate leakage by increasing fluid volume.

I am not sure why there is typically a delay between physical exertion and the experience of the most acute symptoms of post-exertional malaise. One possibility is that it takes time for the tissue inundated with fluid to feel the full effects of the hypoxic conditions. Another possibility is that a biphasic reaction triggered during physical exertion leads to the release of a mediator that causes heightened endothelial dysfunction and fluid release.

Further research is needed into the causes of endothelial dysfunction and damage (in addition to initial infection and inflammatory overreaction, consider major “crashes,” mast cell activations, surgeries and microclots as additional contributors) and appropriate treatment.

References

1. Wirth KJ, Scheibenbogen C, Paul F. An attempt to explain the neurological symptoms of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome. J Transl Med. 2021;19:471. https://doi.org/10.1186/s12967-021-03143-3.

Article PubMed PubMed Central Google Scholar

2. For background, see Lubell, J. To speed progress in treating chronic conditions, engage patients and caregivers as research partners. 2021 Sept.20 In: BMJ Opinion. https://blogs.bmj.com/bmj/2021/09/20/to-speed-progress-in-treating-chronic-conditions-engage-patients-and-caregivers-as-research-partners/

3. Allen M, Schwartz M, Herbst KL. Interstitial Fluid in Lipedema and Control Skin. Womens Health Rep (New Rochelle). 2020;1(1):480–7. https://doi.org/10.1089/whr.2020.0086.PMID:33786515;PMCID:PMC7784769.

Article Google Scholar

4. Herbst KL. Subcutaneous Adipose Tissue Diseases: Dercum Disease, Lipedema, Familial Multiple Lipomatosis, and Madelung Disease. [Updated 2019 Dec 14]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. South Dartmouth (MA).

Source: Lubell J. Letter: Could endothelial dysfunction and vascular damage contribute to pain, inflammation and post-exertional malaise in individuals with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)? J Transl Med. 2022 Jan 24;20(1):40. doi: 10.1186/s12967-022-03244-7. PMID: 35073915. https://translational-medicine.biomedcentral.com/articles/10.1186/s12967-022-03244-7