Prevalence of symptoms, comorbidities, fibrin amyloid microclots and platelet pathology in individuals with Long COVID..., 2022, Pretorius, Kell et al

Abstract
Background
Fibrin(ogen) amyloid microclots and platelet hyperactivation previously reported as a novel finding in South African patients with the coronavirus 2019 disease (COVID-19) and Long COVID/Post-Acute Sequelae of COVID-19 (PASC), might form a suitable set of foci for the clinical treatment of the symptoms of Long COVID/PASC. A Long COVID/PASC Registry was subsequently established as an online platform where patients can report Long COVID/PASC symptoms and previous comorbidities.

Methods
In this study, we report on the comorbidities and persistent symptoms, using data obtained from 845 South African Long COVID/PASC patients. By using a previously published scoring system for fibrin amyloid microclots and platelet pathology, we also analysed blood samples from 80 patients, and report the presence of significant fibrin amyloid microclots and platelet pathology in all cases.

Results
Hypertension, high cholesterol levels (dyslipidaemia), cardiovascular disease and type 2 diabetes mellitus (T2DM) were found to be the most important comorbidities. The gender balance (70% female) and the most commonly reported Long COVID/PASC symptoms (fatigue, brain fog, loss of concentration and forgetfulness, shortness of breath, as well as joint and muscle pains) were comparable to those reported elsewhere. These findings confirmed that our sample was not atypical. Microclot and platelet pathologies were associated with Long COVID/PASC symptoms that persisted after the recovery from acute COVID-19.

Conclusions
Fibrin amyloid microclots that block capillaries and inhibit the transport of O2 to tissues, accompanied by platelet hyperactivation, provide a ready explanation for the symptoms of Long COVID/PASC. Removal and reversal of these underlying endotheliopathies provide an important treatment option that urgently warrants controlled clinical studies to determine efficacy in patients with a diversity of comorbidities impacting on SARS-CoV-2 infection and COVID-19 severity. We suggest that our platelet and clotting grading system provides a simple and cost-effective diagnostic method for early detection of Long COVID/PASC as a major determinant of effective treatment, including those focusing on reducing clot burden and platelet hyperactivation.

Full text: https://cardiab.biomedcentral.com/articles/10.1186/s12933-022-01579-5

 

This one is quite frustratingly vague and doesn't seem to add much to their previous findings. There are two parts:

1. Data from their registry of 845 patients with Long Covid. This shows common symptoms, but nothing new that we haven't seen before in much larger studies. Then they discuss linking pre-existing comorbidities to Long Covid and to particular symptoms, but I don't think they found much. High blood pressure, high cholesterol and T2DM were common in people with LC, but they don't compare the rate to rates in the general population (where these are of course also common). There's something about which comorbidities are associated with which LC symptoms, but that seems quite likely to be noise given the sample size.
2. They examined blood from 80 LC patients and found platelet pathologies and microclots in all of them. They don't seem to have looked at blood from any controls. They scored 30 of them on their three separate 1-4 scales (no details on how they selected these 30) and then added the scores up. The result: "Our overall platelet and microclot scoring results for 30 of the 80 patients were 7 ± 1.3, pointing to moderate activation." Seems kind of meaningless without scores from controls or those with other diseases. Nothing in here about the resistance of these microclots to being broken down, which I understand they think is important and was featured in their previous LC microclots paper.