Tag: long covid pathophysiology

Post COVID syndrome: A novel challenge and threat to international health

Abstract:

The global pandemic caused by the SARS-CoV-2 virus has affected every continent worldwide. The novelty of this virus, its mutations and the rapid speed and unprecedented rate at which it has torn through the global community has in turn lead to an innate lack of knowledge and information about the actual disease caused and the severity of the complications associated with COVID-19.

The SARS-CoV-2 virus has been infecting individuals since 2019 and now as of 2022 has been circulating for just over 2 years within the global populous. As the number of cases have risen globally over this period (some of which having contracted the virus twice) further endeavours have been undertaken to better understand the pathogenesis and natural progression of the disease. A condition reported in some cases with extended bouts of sickness or symptoms following the initial infection with COVID was labelled “long COVID” towards the earlier phases of the pandemic (in the spring of 2020), but has only recently gained the global media and medical attention due to its affliction of more individuals on a global basis and has thus warranted further investigation.

Long COVID is described as a persistent, long-term state of poor health following an infection with COVID-19. The effect of Long COVID is multisystemic in nature with a wide array of signs and symptoms. The most commonly reported clinical features of long COVID are: headaches, myalgia, chest pain, rashes, abdominal pain, shortness of breath, palpitations, anosmia, persistent cough, brain fogs, forgetfulness, depression, insomnia, fatigue and anxiety. This research aims to explore the symptomatology, pathophysiology as well as the treatment and prevention of Long COVID.

Source: Banerjee I, Robinson J, Leclézio A, Sathian B, Banerjee I. Post COVID syndrome: A novel challenge and threat to international health. Nepal J Epidemiol. 2022 Jun 30;12(2):1215-1219. doi: 10.3126/nje.v12i2.46149. PMID: 35974973; PMCID: PMC9374107.  https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9374107/ (Full text)

Long-COVID neurological symptoms are associated with D-dimer levels in COVID-19 patients

Abstract:

Background: Coronavirus disease 2019 (COVID-19) is a disease designated as a global pandemic by the WHO that can manifest clinically as neurological disorders that can occur in the acute phase or after the acute phase (long COVID-19), such as headache, myalgia, anosmia, and cognitive impairment. These neurological disorders as symptoms of long COVID-19 are presumably caused by hypercoagulable conditions characterized by an increase in D-dimer level. This study aims to determine the correlation of long COVID-19 neurological symptoms with hypercoagulable conditions and the role of D-dimer as a biomarker of long COVID-19 neurological symptoms.

Methods: This was a cross-sectional study involving 31 patients with long COVID-19 symptoms. Admitted long COVID-19 cases with recorded D-dimer levels and definitive outcomes were included consecutively. Long COVID-19 neurological symptoms were collected. D-dimer level was measured using immunofluorescence assay and reported in fibrinogen equivalent units (ìg/mL). The correlation between D-dimer levels and neurological clinical manifestations was assessed by using ordinal regression analysis. The p-value of <0.05 was considered statistically significant.

Results: The mean age of the subjects was 38.81 ± 11.58 years and 18 (58.06%) were female. Long COVID neurological symptoms comprised myalgia, anosmia and cephalgia, and most subjects complained of myalgia (80.65%). On multivariable analysis, long-COVID-19 neurological symptoms were significantly correlated with D-dimer [odds ratio (OR) = 1.05; p=0.020].

Conclusion: The number of neurological long COVID symptoms were significantly correlated with level of D-Dimer. Ultimately, more clarity is needed on the neurological impact of COVID-19, its diagnosis, and its treatment.

Source: Mirawati, D. K., Budianto, P., Danuaji, R., Subandi, S., Ristinawati, I., & Prabaningtyas, H. R. (2022). Long-COVID neurological symptoms are associated with D-dimer levels in COVID-19 patients. Universa Medicina, 41(2), 169–175. https://doi.org/10.18051/UnivMed.2022.v41.169-175 https://univmed.org/ejurnal/index.php/medicina/article/view/1246

COVID-19 and Therapeutic Apheresis

Abstract:

The COVID-19 pandemic, caused by the SARS-CoV-2 virus, is an unprecedented challenge for the global community. The pathogenesis of COVID-19, its complications and long term sequelae (so called Long/Post-COVID) include, in addition to the direct virus-induced tissues injury, multiple secondary processes, such as autoimmune response, impairment of microcirculation, and hyperinflammation. Similar pathological processes, but in the settings of neurological, cardiovascular, rheumatological, nephrological, and dermatological diseases can be successfully treated by powerful methods of Therapeutic Apheresis (TA).

We describe here the rationale and the initial attempts of TA treatment in severe cases of acute COVID-19. We next review the evidence for the role of autoimmunity, microcirculatory changes and inflammation in pathogenesis of Long/Post COVID and the rationale for targeting those pathogenic processes by different methods of TA. Finally, we discuss the impact of COVID-19 pandemic on patients, who undergo regular TA treatments due to their underlying chronic conditions, with the specific focus on the patients with inherited lipid diseases being treated at the Dresden University Apheresis Center.

Source: Tselmin S, Julius U, Jarzebska N, Rodionov R. COVID-19 and Therapeutic Apheresis. Horm Metab Res. 2022 Aug;54(8):571-577. doi: 10.1055/a-1864-9482. Epub 2022 Aug 9. PMID: 35944525.  https://pubmed.ncbi.nlm.nih.gov/35944525/

A Review of Respiratory Post-Acute Sequelae of COVID-19 (PASC) and the Potential Benefits of Pulmonary Rehabilitation

Abstract:

With the SARS-CoV-2 pandemic continuing into its third year, the number of patients who survive acute COVID-19 infection but go on to develop long-term symptoms is increasing daily. Those individuals who experience one or more of a variety of persistent symptoms post-COVID-19 are now diagnosed with the syndrome called post-acute sequelae of COVID-19 (PASC), often colloquially called “Long COVID.” This article discusses relevant research and current hypotheses regarding the pathophysiology and management of respiratory symptoms of PASC, in order to provide primary care physicians with context for management of this heterogeneous population. We focus on the growing body of research that supports the use of pulmonary rehabilitation for patients with PASC to improve symptoms and quality of life.

Source: Simon M, Simmons JE. A Review of Respiratory Post-Acute Sequelae of COVID-19 (PASC) and the Potential Benefits of Pulmonary Rehabilitation. R I Med J (2013). 2022 Sep 1;105(7):11-15. PMID: 35930484.  https://pubmed.ncbi.nlm.nih.gov/35930484/ http://rimed.org/rimedicaljournal/2022/09/2022-09-11-covid-simon.pdf (Full text available as PDF file)

Long COVID endotheliopathy: hypothesized mechanisms and potential therapeutic approaches

Abstract:

SARS-CoV-2–infected individuals may suffer a multi–organ system disorder known as “long COVID” or post-acute sequelae of SARS-CoV-2 infection (PASC). There are no standard treatments, the pathophysiology is unknown, and incidence varies by clinical phenotype.

Acute COVID-19 correlates with biomarkers of systemic inflammation, hypercoagulability, and comorbidities that are less prominent in PASC. Macrovessel thrombosis, a hallmark of acute COVID-19, is less frequent in PASC. Female sex at birth is associated with reduced risk for acute COVID-19 progression, but with increased risk of PASC. Persistent microvascular endotheliopathy associated with cryptic SARS-CoV-2 tissue reservoirs has been implicated in PASC pathology.

Autoantibodies, localized inflammation, and reactivation of latent pathogens may also be involved, potentially leading to microvascular thrombosis, as documented in multiple PASC tissues. Diagnostic assays illuminating possible therapeutic targets are discussed.

Source: Ahamed J, Laurence J. Long COVID endotheliopathy: hypothesized mechanisms and potential therapeutic approaches. J Clin Invest. 2022 Aug 1;132(15):e161167. doi: 10.1172/JCI161167. PMID: 35912863; PMCID: PMC9337829. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9337829/ (Full text)

Persistent capillary rarefication in long COVID syndrome

Abstract:

Background: Recent studies have highlighted Coronavirus disease 2019 (COVID-19) as a multisystemic vascular disease. Up to 60% of the patients suffer from long-term sequelae and persistent symptoms even 6 months after the initial infection.

Methods: This prospective, observational study included 58 participants, 27 of whom were long COVID patients with persistent symptoms > 12 weeks after recovery from PCR-confirmed SARS-CoV-2 infection. Fifteen healthy volunteers and a historical cohort of critically ill COVID-19 patients (n = 16) served as controls. All participants underwent sublingual videomicroscopy using sidestream dark field imaging. A newly developed version of Glycocheck™ software was used to quantify vascular density, perfused boundary region (PBR-an inverse variable of endothelial glycocalyx dimensions), red blood cell velocity (VRBC) and the microvascular health score (MVHS™) in sublingual microvessels with diameters 4-25 µm.

Measurements and main results: Although dimensions of the glycocalyx were comparable to those of healthy controls, a µm-precise analysis showed a significant decrease of vascular density, that exclusively affected very small capillaries (D5: – 45.16%; D6: – 35.60%; D7: – 22.79%). Plotting VRBC of capillaries and feed vessels showed that the number of capillaries perfused in long COVID patients was comparable to that of critically ill COVID-19 patients and did not respond adequately to local variations of tissue metabolic demand. MVHS was markedly reduced in the long COVID cohort (healthy 3.87 vs. long COVID 2.72 points; p = 0.002).

Conclusions: Our current data strongly suggest that COVID-19 leaves a persistent capillary rarefication even 18 months after infection. Whether, to what extent, and when the observed damage might be reversible remains unclear.

Source: Osiaevi I, Schulze A, Evers G, Harmening K, Vink H, Kümpers P, Mohr M, Rovas A. Persistent capillary rarefication in long COVID syndrome. Angiogenesis. 2022 Aug 11:1–9. doi: 10.1007/s10456-022-09850-9. Epub ahead of print. PMID: 35951203; PMCID: PMC9366128. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9366128/ (Full text)

Distinguishing features of Long COVID identified through immune profiling

Abstract:

SARS-CoV-2 infection can result in the development of a constellation of persistent sequelae following acute disease called post-acute sequelae of COVID-19 (PASC) or Long COVID. Individuals diagnosed with Long COVID frequently report unremitting fatigue, post-exertional malaise, and a variety of cognitive and autonomic dysfunctions; however, the basic biological mechanisms responsible for these debilitating symptoms are unclear. Here, 215 individuals were included in an exploratory, cross-sectional study to perform multi-dimensional immune phenotyping in conjunction with machine learning methods to identify key immunological features distinguishing Long COVID.

Marked differences were noted in specific circulating myeloid and lymphocyte populations relative to matched control groups, as well as evidence of elevated humoral responses directed against SARS-CoV-2 among participants with Long COVID. Further, unexpected increases were observed in antibody responses directed against non-SARS-CoV-2 viral pathogens, particularly Epstein-Barr virus.

Analysis of circulating immune mediators and various hormones also revealed pronounced differences, with levels of cortisol being uniformly lower among participants with Long COVID relative to matched control groups. Integration of immune phenotyping data into unbiased machine learning models identified significant distinguishing features critical in accurate classification of Long COVID, with decreased levels of cortisol being the most significant individual predictor. These findings will help guide additional studies into the pathobiology of Long COVID and may aid in the future development of objective biomarkers for Long COVID.

Source: Jon Klein, Jamie Wood, Jillian Jaycox, Peiwen Lu, Rahul M. Dhodapkar, Jeffrey R. Gehlhausen, Alexandra Tabachnikova, Laura Tabacof, Amyn A. Malik, Kathy Kamath, Kerrie Greene, Valter Silva Monteiro, Mario Pena-Hernandez, Tianyang Mao, Bornali Bhattacharjee, Takehiro Takahashi, Carolina Lucas, Julio Silva, Dayna Mccarthy, Erica Breyman, Jenna Tosto-Mancuso, Yile Dai, Emily Perotti, Koray Akduman, Tiffany Tzeng, Lan Xu, Inci Yildirim, Harlan M. Krumholz, John Shon, Ruslan Medzhitov, Saad B. Omer, David van Dijk, Aaron M. Ring, David Putrino, Akiko Iwasaki. Distinguishing features of Long COVID identified through immune profiling. medRxiv 2022.08.09.22278592; doi: https://doi.org/10.1101/2022.08.09.22278592

Serum of Post-COVID-19 Syndrome patients with or without ME/CFS differentially affects endothelial cell function in vitro

Abstract:

A proportion of COVID-19 reconvalescent patients develop post-COVID-19 syndrome (PCS) including a subgroup fulfilling diagnostic criteria of Myalgic encephalomyelitis/Chronic Fatigue Syndrome (PCS/CFS). Recently, endothelial dysfunction (ED) has been demonstrated in these patients, but the mechanisms remain elusive. Therefore, we investigated the effects of patients’ sera on endothelia cells (ECs) in vitro.
PCS (n = 17), PCS/CFS (n = 13), and healthy controls (HC, n = 14) were screened for serum anti-endothelial cell autoantibodies (AECAs) and dysregulated cytokines. Serum-treated ECs were analysed for the induction of activation markers and the release of small molecules by flow cytometry. Moreover, the angiogenic potential of sera was measured in a tube formation assay.
While only marginal differences between patient groups were observed for serum cytokines, AECA binding to ECs was significantly increased in PCS/CFS patients. Surprisingly, PCS and PCS/CFS sera reduced surface levels of several EC activation markers. PCS sera enhanced the release of molecules associated with vascular remodelling and significantly promoted angiogenesis in vitro compared to the PCS/CFS and HC groups. Additionally, sera from both patient cohorts induced the release of molecules involved in inhibition of nitric oxide-mediated endothelial relaxation.
Overall, PCS and PCS/CFS patients′ sera differed in their AECA content and their functional effects on ECs, i.e., secretion profiles and angiogenic potential. We hypothesise a pro-angiogenic effect of PCS sera as a compensatory mechanism to ED which is absent in PCS/CFS patients.
Source: Flaskamp L, Roubal C, Uddin S, Sotzny F, Kedor C, Bauer S, Scheibenbogen C, Seifert M. Serum of Post-COVID-19 Syndrome Patients with or without ME/CFS Differentially Affects Endothelial Cell Function In Vitro. Cells. 2022; 11(15):2376. https://doi.org/10.3390/cells11152376  https://www.mdpi.com/2073-4409/11/15/2376/htm (Full text)

High-density EEG sleep correlates of cognitive and affective impairment at 12-month follow-up after COVID-19

Abstract:

Objective: To disentangle the pathophysiology of cognitive/affective impairment in Coronavirus Disease-2019 (COVID-19), we studied long-term cognitive and affective sequelae and sleep high-density electroencephalography (EEG) at 12-month follow-up in people with a previous hospital admission for acute COVID-19.

Methods: People discharged from an intensive care unit (ICU) and a sub-intensive ward (nonICU) between March and May 2020 were contacted between March and June 2021. Participants underwent cognitive, psychological, and sleep assessment. High-density EEG recording was acquired during a nap. Slow and fast spindles density/amplitude/frequency and source reconstruction in brain gray matter were extracted. The relationship between psychological and cognitive findings was explored with Pearson correlation.

Results: We enrolled 33 participants ( 17 nonICU) and 12 controls. We observed a lower Physical Quality of Life index, higher post-traumatic stress disorder (PTSD) score, and a worse executive function performance in nonICU participants. Higher PTSD and Beck Depression Inventory scores correlated with lower executive performance. The same group showed a reorganization of spindle cortical generators.

Conclusions: Our results show executive and psycho-affective deficits and spindle alterations in COVID-19 survivors – especially in nonICU participants – after 12 months from discharge.

Significance: These findings may be suggestive of a crucial contribution of stress experienced during hospital admission on long-term cognitive functioning.

Source: Rubega M, Ciringione L, Bertuccelli M, Paramento M, Sparacino G, Vianello A, Masiero S, Vallesi A, Formaggio E, Del Felice A. High-density EEG sleep correlates of cognitive and affective impairment at 12-month follow-up after COVID-19. Clin Neurophysiol. 2022 Jun 15;140:126-135. doi: 10.1016/j.clinph.2022.05.017. Epub ahead of print. PMID: 35763985; PMCID: PMC9292469. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9292469/ (Full text)

Microvascular Injury in the Brains of Patients with Covid-19

To the Editor:

We conducted postmortem high-resolution magnetic resonance imaging (magnetic resonance microscopy) of the brains of patients with coronavirus disease 2019 (Covid-19) (median age, 50 years) and histopathological examination that focused on microvascular changes in the olfactory bulb and brain stem. (See the Materials and Methods section in the Supplementary Appendix, available with the full text of this letter at NEJM.org.) Images were obtained from the brains of 13 patients with the use of an 11.7-Tesla scanner at a resolution of 25 μm for the olfactory bulb and at a resolution of 100 μm for the brain. Abnormalities were seen in the brains of 10 patients.

We examined the brains of patients that showed abnormalities by means of multiplex fluorescence imaging (in 5 patients) and by means of chromogenic immunostaining (in 10 patients). We performed conventional histopathological examination of the brains of 18 patients. Fourteen patients had chronic illnesses, including diabetes and hypertension, and 11 had been found dead or had died suddenly and unexpectedly. Of the 16 patients with available medical histories, 1 had delirium, 5 had mild respiratory symptoms, 4 had acute respiratory distress syndrome, 2 had pulmonary embolism, and the symptoms were not known in 3.

Read the rest of this letter HERE.

Source: Lee MH, Perl DP, Nair G, Li W, Maric D, Murray H, Dodd SJ, Koretsky AP, Watts JA, Cheung V, Masliah E, Horkayne-Szakaly I, Jones R, Stram MN, Moncur J, Hefti M, Folkerth RD, Nath A. Microvascular Injury in the Brains of Patients with Covid-19. N Engl J Med. 2021 Feb 4;384(5):481-483. doi: 10.1056/NEJMc2033369. Epub 2020 Dec 30. PMID: 33378608; PMCID: PMC7787217. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7787217/ (Full text)