In this edition, we explore the potential role of inflammation in the condition, the retraction and republishing of a highly-cited study on Long COVID, and more. We hope this newsletter provides valuable insights for both patients and healthcare providers. Seems like research news is slowing down as we start to get into the summer, hopefully things start to pick up again soon.
Without further ado, lets jump into things!
Media
Article: Patients With Post-COVID Cognitive Symptoms May Have Gliosis
DEFINITIONS:
Gliosis: a proliferation of astrocytes in damaged areas of the central nervous system.
PET: Positron emission tomography is a nuclear medicine imaging technique which uses radioactive substances to evaluate and measure the physiological functions of different organs in the body.
SUMMARY:
Patients with persistent depressive or cognitive symptoms after mild to moderate COVID-19 (COVID-DC) may have gliosis and inflammation, data suggest.
The study showed gliosis in areas of the brain, may explain some of the long-term, persistent depressive symptoms reported by patients post-COVID-19.
PET scans were used to detect gliosis and imaged through TSPO imaging.
The ligand, however, is not specific for gliosis, and other measures of neuroimaging modalities assessing circuitry and neurochemistry are needed.
My Take:
This study is also significant because it provides a better understanding of how the immune reaction in the blood transitions to the brain.
Article: Decoding Long COVID: Is Overactive Inflammation the Missing Key?
DEFINITIONS:
Anti-inflammatory drugs: Drugs that work to reduce inflammation in the body, often used to treat conditions such as arthritis, asthma, and certain autoimmune diseases.
SUMMARY:
A study from the Allen Institute and Fred Hutchinson Cancer Center found that an overactive inflammatory response might be a cause of many long COVID cases.
These findings suggest that certain types of anti-inflammatory drugs could potentially help alleviate symptoms for some patients with long COVID, promoting the idea of precision medicine in treating this condition.
By examining proteins found in the bloodstream, the researchers identified a specific group of molecules related to inflammation.
My Take:
The research suggests certain anti-inflammatory drugs could be used to alleviate symptoms of long COVID, but more research is needed to determine which treatment would work for different individuals.
Article: Highly cited Lancet long COVID study retracted and republished – Retraction Watch
DEFINITIONS:
Expression of Concern: An expression of concern (EoC) is an editorial statement alerting readers to potentially problematic articles and informing the scientific community that a more comprehensive investigation into the validity of the research results is ongoing.
SUMMARY:
One of the first studies of long COVID has been retracted and replaced seven months after editors marked it with an expression of concern citing “data errors.” The original paper, “6-month consequences of COVID-19 in patients discharged from hospital: a cohort study,” was published in The Lancet in January 2021.
It was “the first large cohort study with 6-months’ follow-up” of people hospitalized with COVID-19, according to an editorial published simultaneously, and has been cited more than 2,000 times, according to Clarivate’s Web of Science.
Last November, the article received an expression of concern stating that a researcher had contacted the journal about inconsistencies between that study and a paper published in August 2021, also in The Lancet, describing the same cohort of patients after one year of follow up.
After their investigation, the editors decided to retract the article and replace it with a corrected version.
Research
DEFINITIONS:
T cells: white blood cells that are crucial to the immune system's function in recognizing and killing pathogens.
CD8+ T cells: a subset of T cells that directly kill infected cells by recognizing and binding to antigenic peptides presented on the surface of infected cells in association with MHC class I molecules.
SUMMARY:
The study observed the dominance of CD8+ T cells recognizing SARS-Co V-2-unique rather than Co V-common epitopes, indicating that newly expanding T-cell clones may have a relatively high contribution to the SARS-Co V-2 immune response compared to potentially pre-existing cross-reactive T-cell clones.
Critically ill patients experienced a reduction in the breadth of Co V-common and SARS-Co V-2 specific TCR repertoires and respective response diversities, which could explain the deleterious contribution of cross-reactive T cells in COVID-19 severity.
Monitoring TCR repertoires and T-cell response in infected and vaccinated individuals could be helpful to better assess the necessity of an intervention to ensure and preserve adequate protection against any emerging SARS-Co V-2 variant.
DEFINITIONS:
Endocarditis: an infection of the inner lining of the heart chambers and valves.
SUMMARY:
COVID-19 infection has been known to cause cardiovascular complications, including endocarditis, which has a low prevalence.
Tocilizumab and corticosteroids are some of the treatment options in severe COVID-19 infection.
Using these agents can lead to immunocompromising, making the patient more susceptible to secondary infections, including endocarditis.
The presented case studies discuss two cases of bacterial endocarditis as a potential adverse effect after administering tocilizumab, corticosteroids, and COVID-19 infection.
Both patients tested positive for Polymerase chain reaction (PCR) less than one month ago and were treated with tocilizumab and corticosteroid.
My Take:
The presented case studies demonstrate the potential adverse effects of administering tocilizumab and corticosteroids in COVID-19 patients, such as bacterial endocarditis.
It seems like even 3 years after the start of the pandemic, a new adverse effect of Covid is discovered
DEFINITIONS:
Dyspnea: a medical term used to describe shortness of breath or difficulty breathing.
SUMMARY:
Dyspnea occurs in around 36% of individuals who have recovered from COVID-19 and is a common symptom of post-COVID syndrome.
Currently, pulmonary function and exercise tests are recommended to clarify dyspneic symptoms; however, these tests are performed at rest despite most patients reporting dyspnea during exertion.
This may lead to misleading results as some pathologies only become visible on exertion.
Electrical impedance tomography (EIT) is a non-invasive method to visualize lung ventilation that is suitable for visualizing disturbed ventilation both at rest and under stress.
The potential value of EIT to diagnose dyspnea should be investigated.
My Take:
Like many Long Covid symptoms this article showcases the need for a better diagnostic tool to understand the effects of post-COVID syndrome fully.
DEFINITIONS:
RTEL1: a gene relevant to the homeostasis of telomeres.
Telomeres: the repeating DNA-protein complex at the end of chromosomes that protects the chromosomes.
SUMMARY:
A direct association between COVID-19 and RTEL1 variants is not generally acknowledged.
Up to 8.6% of severe COVID-19 patients bear RTEL1 ultra-rare variants, and this subgroup can be recognized as a predictive marker of COVID-19 severity.
RTEL1 ultra-rare variants are also a marker of pathological evolution in pulmonary fibrosis in the post-COVID phase.
This notion can be used for rapid screening in hospitalized infected people, for vaccine prioritization, and appropriate follow-up assessment for subjects at risk.
My Take:
This research highlights the association between RTEL1 ultra-rare variants and severe COVID-19 cases.
These variants can be a predictive marker of COVID-19 severity and a marker of pathological evolution in pulmonary fibrosis in the post-COVID phase.
SUMMARY:
Approximately 96% of patients with postural orthostatic tachycardia syndrome (PoTS) report cognitive complaints.
Compared with HCs, PoTS participants showed impaired cognitive attention and executive function in the upright position that did not improve in the legs crossed position.
My Take:
The findings suggest that leg crossing, which is recommended during acute dizziness in PoTS therapy, may not improve cognitive deficits in these patients.
DEFINITIONS:
.
Global Deficit Score (GDS): an evidence-based definition of cognitive impairment that is demographically and practice effect-corrected longitudinally.
Kynurenine Pathway (KP): a pathway important in immune tolerance, neurotoxicity, and vascular injury.
SUMMARY:
Mild to moderate cognitive impairment was present in 16%–26% participants across the study period with 46.5% having impairment at one or more time points during the study period. While no patient demonstrated severe cognitive impairment, this prevalence rate was greater than pre-COVID normative references
The study also looked at various peripheral neurobiomarkers and the dysregulation of the kynurenine pathway in COVID-19 infection.
While PASC associated with an abnormal KYN/TRP ratio, the KP association with objective cognitive impairment and function was the strongest and most robust.
Great reporting as always! I found the gliosis possibility intriguing. Perhaps that imaging could become a standard procedure prescribed for long Covid px presenting with cognitive deficits?