Increased circulating fibronectin, depletion of natural IgM and heightened EBV, HSV-1 reactivation in ME/CFS and long COVID

Abstract:

Myalgic Encephalomyelitis/ Chronic Fatigue syndrome (ME/CFS) is a complex, debilitating, long-term illness without a diagnostic biomarker. ME/CFS patients share overlapping symptoms with long COVID patients, an observation which has strengthened the infectious origin hypothesis of ME/CFS. However, the exact sequence of events leading to disease development is largely unknown for both clinical conditions.

Here we show antibody response to herpesvirus dUTPases, particularly to that of Epstein-Barr virus (EBV) and HSV-1, increased circulating fibronectin (FN1) levels in serum and depletion of natural IgM against fibronectin ((n)IgM-FN1) are common factors for both severe ME/CFS and long COVID. We provide evidence for herpesvirus dUTPases-mediated alterations in host cell cytoskeleton, mitochondrial dysfunction and OXPHOS.

Our data show altered active immune complexes, immunoglobulin-mediated mitochondrial fragmentation as well as adaptive IgM production in ME/CFS patients. Our findings provide mechanistic insight into both ME/CFS and long COVID development. Finding of increased circulating FN1 and depletion of (n)IgM-FN1 as a biomarker for the severity of both ME/CFS and long COVID has an immediate implication in diagnostics and development of treatment modalities.

Source: Zheng Liu, Claudia Hollmann, Sharada Kalanidhi, Arnhild Grothey, Samuel Keating, Irene Mena-Palomo, Stephanie Lamer, Andreas Schlosser, Agnes Kaiping, Carsten Scheller, Franziska Sotzny, Anna Horn, Carolin Nuernberger, Vladimir Cejka, Boshra Afshar, Thomas Bahmer, Stefan Schreiber, Joerg Janne Vehreschild, Olga Milljukov, Christian Schaefer, Luzie Kretzler, Thomas Keil, Jens-Peter Reese, Felizitas A Eichner, Lena Schmidbauer, Peter U Heuschmann, Stefan Stoerk, Caroline Morbach, Gabriela Riemekasten, Niklas Beyersdorf, Carmen Scheibenbogen, Robert K Naviaux, Marshall Williams, Maria E Ariza, Bhupesh Kumar Prusty. Increased circulating fibronectin, depletion of natural IgM and heightened EBV, HSV-1 reactivation in ME/CFS and long COVID. medRxiv 2023.06.23.23291827; doi: https://doi.org/10.1101/2023.06.23.23291827 https://www.medrxiv.org/content/10.1101/2023.06.23.23291827v1 (Full text available as PDF file)

Viral persistence in children infected with SARS-CoV-2: current evidence and future research strategies

Summary:

In this Personal View, we discuss current knowledge on SARS-CoV-2 RNA or antigen persistence in children infected with SARS-CoV-2. Based on the evidence that the virus can persist in adults, we have done a literature review and analysed studies that looked for SARS-CoV-2 RNA or antigens in children undergoing autopsy, biopsy, or surgery for either death from COVID-19 or multisystem inflammatory syndrome, or assessments for long COVID-19 or other conditions.
Our analysis suggests that in children, independent from disease severity, SARS-CoV-2 can spread systemically and persist for weeks to months. We discuss what is known about the biological effects of viral persistence for other viral infections and highlight new scenarios for clinical, pharmacological, and basic research exploration. Such an approach will improve the understanding and management of post-viral syndromes.
Source: Danilo Buonsenso, Laura Martino, Rosa Morello, Francesco Mariani, Kelly Fearnley, Piero . Viral persistence in children infected with SARS-CoV-2: current evidence and future research strategies. The Lancet Microbe. Published: June 26, 2023. https://www.thelancet.com/journals/lanmic/article/PIIS2666-5247(23)00115-5/fulltext (Full text)

Cardiac MRI Findings in Patients Clinically Referred for Evaluation of Post-Acute Sequelae of SARS-CoV-2 Infection

Abstract:

Persistent or recurrent cardiovascular symptoms have been identified as one of the hallmarks of long-COVID or post-acute sequelae of SARS-CoV-2 infection (PASC). The purpose of this study was to determine the prevalence and extent of cardiac abnormalities in patients referred for cardiac MRI due to clinical evidence of PASC. To investigate this, two tertiary care hospitals identified all patients who were referred for cardiac MRI under the suspicion of PASC in a 2-year period and retrospectively included them in this study.
Patients with previously known cardiac diseases were excluded. This resulted in a total cohort of 129 patients (63, 51% female; age 41 ± 16 years). The majority of patients (57%) showed normal cardiac results. No patient had active myocarditis or an acute myocardial infarction. However, 30% of patients had evidence of non-ischemic myocardial fibrosis, which exceeds the prevalence in the normal adult population and suggests that a possible history of myocarditis might explain persistent symptoms in the PASC setting.
Source: Halfmann MC, Luetkens JA, Langenbach IL, Kravchenko D, Wenzel P, Emrich T, Isaak A. Cardiac MRI Findings in Patients Clinically Referred for Evaluation of Post-Acute Sequelae of SARS-CoV-2 Infection. Diagnostics. 2023; 13(13):2172. https://doi.org/10.3390/diagnostics13132172 https://www.mdpi.com/2075-4418/13/13/2172 (Full text)

The COVID-19 Pandemic and the $16 Trillion Virus

The SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) pandemic is the greatest threat to prosperity and well-being the US has encountered since the Great Depression. This Viewpoint aggregates mortality, morbidity, mental health conditions, and direct economic losses to estimate the total cost of the pandemic in the US on the optimistic assumption that it will be substantially contained by the fall of 2021. These costs far exceed those associated with conventional recessions and the Iraq War, and are similar to those associated with global climate change. However, increased investment in testing and contact tracing could have economic benefits that are at least 30 times greater than the estimated costs of the investment in these approaches.

Read the full text here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7604733/

Also see: The Economic Cost of Long COVID: An Update: https://scholar.harvard.edu/files/cutler/files/long_covid_update_7-22.pdf

Source: Cutler DM, Summers LH. The COVID-19 Pandemic and the $16 Trillion Virus. JAMA. 2020;324(15):1495–1496. doi:10.1001/jama.2020.19759. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7604733/ (Full text)

The Economic Cost of Long COVID: An Update

Relative to my earlier estimate with Lawrence Summers of the cost of long COVID of $2.6 trillion, the higher number here is higher: $3.7 trillion in total. The higher estimate is largely a result of the greater prevalence of long COVID than we had guessed at the time. There are about 10 times the number of people with long COVID as have died of COVID. Because long COVID is so new, there is uncertainty about all of the numbers involved in the calculations. Still, the costs here are conservative, based on only cases to date. The enormity of these costs implies that policy to address long COVID are urgently needed. With costs this high, virtually any amount spent on long COVID detection, treatment, and control would result in benefits far above what it costs.

Read the full text here: https://scholar.harvard.edu/files/cutler/files/long_covid_update_7-22.pdf

Note: See The COVID-19 Pandemic and the $16 Trillion Virus for background.

Source: David M. Cutler. The Economic Cost of Long COVID: An Update. Harvard University.

Impact of Covid-19 disease on thyroid function: longitudinal study

Abstract:

Background: The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic disease (Covid-19) affects thyroid function with different mechanisms: non-thyroidal illness syndrome (NTIS), direct infection of thyroid gland and cytokine storm. We provided the first description of painless atypical thyroiditis coexisting with NTIS in patients hospitalised for moderate-to-severe Covid-19 disease. We aimed to: 1) correlate thyroid dysfunction with Covid-19 disease severity; 2) follow the evolution of thyroid function over time.

Methods: Baseline (at hospital admittance) and longitudinal study of patients hospitalised for moderate-to-severe Covid-19 disease, without known history of thyroid disfunction, assessing serum thyroid function and autoantibodies, inflammatory markers and thyroid ultrasound scan (US). Patients showing at US focal hypoechoic areas suggestive for thyroiditis (thyroiditis-areas) also underwent thyroid 99mTc or I123 uptake scan.

Results: 183 Covid-19 patients were studied baseline, of whom 63 (34%) were already on steroid treatment before hospital admission, thus were not considered for TSH analysis. Decreased serum TSH positively correlated with albumin (P=0.02) and lymphocyte count (P<0.01) but not with C-reactive-protein (P=0.12) and interleukin-6 (P=0.10); TSH also progressively and inversely correlated to the need of oxygen support (P=0.02). Serum FT3 correlated positively with albumin (P<0.01) and inversely with D-dimer (P=0.02). Baseline thyroid US scan showed thyroiditis-areas in 18/65 (28%) patients, associated with reduced thyroid uptake at 99mTc/I123 scintigraphy in 14/17 (82%) cases. Thyroiditis-areas were more frequent among patients with baseline low TSH (6/10, 60%) compared with those with normal TSH (10/40, 25%, P=0.034). The patients with thyroiditis-areas also had higher baseline FT4 (P=0.018) and IL-6 (P=0.016) compared with those with normal thyroid US. Follow-up analysis was conducted in 75/183 (41%) patients; thyroid function and inflammatory markers normalized at all time-points in nearly all cases and no increase of thyroid autoantibodies positivity was observed. The thyroiditis-areas, even if often reduced in size, were still present after 6 and 12 months in 13/15 (87%) and 6/12 (50%) patients, respectively. After 9 months the thyroid uptake at 99mTc/I123 scintigraphy was still reduced in 4/6 (67%) patients, even if partially recovered (mean +28%) compared with baseline.

Conclusions: Thyroid dysfunction during moderate-to-severe Covid-19 disease is mild and transient, and thyroid hormones correlate with disease severity. Thyroiditis-areas at US occur frequently and may persist after one year, even if reduced in size; long-term consequences are unknown. The association of thyroiditis-areas with low TSH and high FT4 and IL-6 serum concentrations support the hypothesis of direct thyroid gland involvement in SARS-CoV-2 infection.

Source: Ilaria Muller, Matteo Varallo, Anita Daturi, Tiziana E Re, Davide Dazzi, Virgilio Longari, Andrea Gori, Giovanna Mantovani , Maura Arosio & Mario Salvi. Impact of Covid-19 disease on thyroid function: longitudinal study. Endocrine Abstracts (2022) 81 RC11.1 | DOI: 10.1530/endoabs.81.RC11.1 https://www.endocrine-abstracts.org/ea/0081/ea0081rc11.1

Tryptophan catabolites, inflammation, and insulin resistance as determinants of chronic fatigue syndrome and affective symptoms in long COVID

Abstract:

Critical COVID-19 disease is accompanied by depletion of plasma tryptophan (TRY) and increases in indoleamine-dioxygenase (IDO)-stimulated production of neuroactive tryptophan catabolites (TRYCATs), including kynurenine (KYN). The TRYCAT pathway has not been studied extensively in association with the physiosomatic and affective symptoms of Long COVID.

In the present study, we measured serum TRY, TRYCATs, insulin resistance (using the Homeostatic Model Assessment Index 2-insulin resistance, HOMA2-IR), C-reactive protein (CRP), physiosomatic, depression, and anxiety symptoms in 90 Long COVID patients, 3–10 months after remission of acute infection.

We were able to construct an endophenotypic class of severe Long COVID (22% of the patients) with very low TRY and oxygen saturation (SpO2, during acute infection), increased kynurenine, KYN/TRY ratio, CRP, and very high ratings on all symptom domains. One factor could be extracted from physiosomatic symptoms (including chronic fatigue-fibromyalgia), depression, and anxiety symptoms, indicating that all domains are manifestations of the common physio-affective phenome.

Three Long COVID biomarkers (CRP, KYN/TRY, and IR) explained around 40% of the variance in the physio-affective phenome. The latter and the KYN/TRY ratio were significantly predicted by peak body temperature (PBT) and lowered SpO2 during acute infection. One validated latent vector could be extracted from the three symptom domains and a composite based on CRP, KYN/TRY, and IR (Long COVID), and PBT and SpO2 (acute COVID-19).

In conclusion, the physio-affective phenome of Long COVID is a manifestation of inflammatory responses during acute and Long COVID, and lowered plasma tryptophan and increased kynurenine may contribute to these effects.

Source: Al-Hakeim HK, Khairi Abed A, Rouf Moustafa S, Almulla AF, Maes M. Tryptophan catabolites, inflammation, and insulin resistance as determinants of chronic fatigue syndrome and affective symptoms in long COVID. Front Mol Neurosci. 2023 Jun 2;16:1194769. doi: 10.3389/fnmol.2023.1194769. PMID: 37333619; PMCID: PMC10272345. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10272345/ (Full text)

Post-COVID sequalae effect in chronic fatigue syndrome: SARS-CoV-2 triggers latent adenovirus in the oral mucosa

Abstract:

The post-viral fatigue syndromes long COVID and myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) have multiple, potentially overlapping, pathological processes. These include persisting reservoirs of virus e.g. SARS-CoV-2 in long COVID patient’s tissues, immune dysregulation with or without reactivation of underlying pathogens, such as Epstein-Barr virus (EBV) and human herpesvirus 6 (HHV6), as we recently described in ME/CFS, and possibly yet unidentified viruses.

In the present study we tested saliva samples from two cohorts for IgG against human adenovirus (HAdV): patients with ME/CFS (n=84) and healthy controls (n=94), with either mild/asymptomatic SARS-CoV-2 infection or no infection. A significantly elevated anti-HAdV IgG response after SARS-CoV-2 infection was detected exclusively in the patient cohort. Longitudinal/time analysis, before and after COVID-19, in the very same individuals confirmed HAdV IgG elevation after. In plasma there was no HAdV IgG elevation.

We conclude that COVID-19 triggered reactivation of dormant HAdV in the oral mucosa of chronic fatigue patients indicating an exhausted dysfunctional antiviral immune response in ME/CFS, allowing reactivation of adenovirus upon stress encounter such as COVID-19.

Source: Ulf Hannestad, Eirini Apostolou, Per Sjogren, Björn Bragée, Olli Polo, Bo C. Bertilson and Anders Rosén. Post-COVID sequalae effect in chronic fatigue syndrome: SARS-CoV-2 triggers latent adenovirus in the oral mucosa. Front. Med. Sec. Infectious Diseases: Pathogenesis and Therapy, Volume 10 – 2023 | doi: 10.3389/fmed.2023.1208181 https://www.frontiersin.org/articles/10.3389/fmed.2023.1208181/abstract

Vagus Nerve Dysfunction in the Post-COVID-19 Condition

Abstract:

Background: The post-COVID-19 condition (PCC) is a disabling syndrome affecting 5-15% of subjects who survive COVID-19. SARS-CoV-2 mediated vagus nerve dysfunction could explain some of the PCC symptoms, including persistent dysphonia, dysphagia, dyspnea, dizziness, tachycardia, orthostatic hypotension, gastrointestinal disturbances or neurocognitive complaints.

Methods: We performed a cross-sectional pilot study in subjects with PCC with symptoms suggesting vagus nerve dysfunction (n=30) and compared them to subjects fully recovered from acute COVID-19 (n=14) and individuals never infected with SARS-CoV-2 (n=16), matched by age and sex. We evaluated the structure and function of the vagus nerve, including dysphonia, dysphagia, and dysautonomia tests, and evaluated the structure and function of respiratory muscles with vagus nerve innervation.

Findings: Participants were mostly (80%) women with median 44 years of age. Their most prevalent symptoms were cognitive dysfunction (83%), dyspnea (80%) and tachycardia (80%). Compared with COVID-19-recovered and uninfected controls, respectively, subjects with PCC were more likely to show thickening and hyperechogenic vagus nerve in neck ultrasounds (mean ± SD left vagus nerve cross-sectional area: 2.4 ± 0.97mm2 vs. 2 ± 0.52mm2 vs. 1.9 ± 0.73 mm2, p=0.080), flattened diaphragmatic curve (47% vs 6% vs 14%, p=0.007), reduced esophageal peristalsis (34% vs 0% vs 21%, p=0.020), gastroesophageal reflux (34% vs 19% vs 7%, p=0.130), hiatal hernia (25% vs 0% vs 7%, p=0.050) and reduced maximal inspiratory pressure in functional respiratory tests (62% vs. 6% vs. 17%, p ≤0.001).

Interpretation: Vagus nerve dysfunction has a central pathogenic role in the pathophysiology of the post-COVID condition.

Source: Lladós, Gemma and Massanella, Marta and Coll-Fernández, Roser and Rodríguez, Raúl and Hernández, Electra and Lucente, Giuseppe and López, Cristina and Loste, Cora and Santos, José Ramón and España-Cueto, Sergio and Nevot, Maria and Muñoz-López, Francisco and Arrieta, Sandra Silva and Brander, Christian and Durà, Maria José and Cuadras, Patricia and Bechini, Jordi and Tenesa, Montserrat and Martinez-Piñeiro, Alicia and Herrero, Cristina and Chamorro, Anna and Garcia, Anna and Grau, Eulalia and Clotet, Bonaventura and Paredes, Roger and Mateu, Lourdes and Unit, Germans Trias Long-COVID, Vagus Nerve Dysfunction in the Post-COVID-19 Condition. Available at SSRN: https://ssrn.com/abstract=4479598 or http://dx.doi.org/10.2139/ssrn.4479598

Increased red blood cell deformation in children and adolescents after SARS-CoV-2 infection

Abstract:

Severe coronavirus disease 2019 (COVID-19) is associated with hyperinflammation, hypercoagulability and hypoxia. Red blood cells (RBCs) play a key role in microcirculation and hypoxemia and are therefore of special interest in COVID-19 pathophysiology. While this novel disease has claimed the lives of many older patients, it often goes unnoticed or with mild symptoms in children.

This study aimed to investigate morphological and mechanical characteristics of RBCs after SARS-CoV-2 infection in children and adolescents by real-time deformability-cytometry (RT-DC), to investigate the relationship between alterations of RBCs and clinical course of COVID-19. Full blood of 121 students from secondary schools in Saxony, Germany, was analyzed. SARS-CoV-2-serostatus was acquired at the same time.

Median RBC deformation was significantly increased in SARS-CoV-2-seropositive compared to seronegative children and adolescents, but no difference could be detected when the infection dated back more than 6 months. Median RBC area was the same in seropositive and seronegative adolescents. ‘

Our findings of increased median RBC deformation in SARS-CoV-2 seropositive children and adolescents until 6 months post COVID-19 could potentially serve as a progression parameter in the clinical course of the disease with an increased RBC deformation pointing towards a mild course of COVID-19.

Source: Eder J, Schumm L, Armann JP, Puhan MA, Beuschlein F, Kirschbaum C, Berner R, Toepfner N. Increased red blood cell deformation in children and adolescents after SARS-CoV-2 infection. Sci Rep. 2023 Jun 17;13(1):9823. doi: 10.1038/s41598-023-35692-6. PMID: 37330522. https://www.nature.com/articles/s41598-023-35692-6 (Full text)