Multiplatform analyses reveal distinct drivers of systemic pathogenesis in adult versus pediatric severe acute COVID-19

Abstract:

The pathogenesis of multi-organ dysfunction associated with severe acute SARS-CoV-2 infection remains poorly understood. Endothelial damage and microvascular thrombosis have been identified as drivers of COVID-19 severity, yet the mechanisms underlying these processes remain elusive. Here we show alterations in fluid shear stress-responsive pathways in critically ill COVID-19 adults as compared to non-COVID critically ill adults using a multiomics approach.

Mechanistic in-vitro studies, using microvasculature-on-chip devices, reveal that plasma from critically ill COVID-19 adults induces fibrinogen-dependent red blood cell aggregation that mechanically damages the microvascular glycocalyx. This mechanism appears unique to COVID-19, as plasma from non-COVID sepsis patients demonstrates greater red blood cell membrane stiffness but induces less significant alterations in overall blood rheology.

Multiomics analyses in pediatric patients with acute COVID-19 or the post-infectious multi-inflammatory syndrome in children (MIS-C) demonstrate little overlap in plasma cytokine and metabolite changes compared to adult COVID-19 patients. Instead, pediatric acute COVID-19 and MIS-C patients show alterations strongly associated with cytokine upregulation. These findings link high fibrinogen and red blood cell aggregation with endotheliopathy in adult COVID-19 patients and highlight differences in the key mediators of pathogenesis between adult and pediatric populations.

Source: Druzak, S., Iffrig, E., Roberts, B.R. et al. Multiplatform analyses reveal distinct drivers of systemic pathogenesis in adult versus pediatric severe acute COVID-19. Nat Commun 14, 1638 (2023). https://doi.org/10.1038/s41467-023-37269-3 (Full text)

Comparison of Symptoms in Covid-19 Acute Infection and Long Covid-19

Abstract:

Background: Relatively little is known about the clinical course of covid-19 and the differences between the symptoms of covid-19 in acute phase of infection and the symptoms of long covid-19 in people with milder outpatient illnesses.

Objective: To compare clinical characteristics of covid-19 in acute infection with long covid-19 (presence of prolonged symptoms for at least 12 weeks, lasting at least 2 months, after acute covid-19 infection, and that are not explained by an alternative diagnosis).

Methodology: Comparison of secondary data among tow previous observational, longitudinal and prospective studies: 1) patients with post-acute covid-19 syndrome from March 15, 2020 to March 31, 2021; and 2) patients with Long covid-19 from March 15, 2020 to October 31, 2022, in the same population in general medicine.

Results: 33 covid-19 in acute phase, with 138 symptoms and 27 Long covid-19 cases with 44 symptoms were included. Respiratory symptoms predominated in both groups. Symptoms in Long covid-19 cases were significantly lower in general symptoms (X2= 5.9539. p= .014), and higher in Circulatory and Genitourinary system (Fisher exact test= 0.05).

Conclusion: Both in Long covid-19 and in covid-19 acute phase respiratory symptoms predominate. But they differ in that the symptoms of long covid-19 are less general than those of covid-19 acute phase, and present more symptoms of almost all organs and systems, those of the Circulatory and Genitourinary system being significant. The symptoms of Long covid-19 vs. acute phase are more debilitating and clinically heterogeneous.

Source: Turabian, Jose. (2023). Comparison of Symptoms in Covid-19 Acute Infection and Long Covid-19. 2694-5843. 10.36266/JCMHR/170.  https://www.researchgate.net/publication/369088222_Comparison_of_Symptoms_in_Covid-19_Acute_Infection_and_Long_Covid-19 (Full text)

Brain autopsies of critically ill COVID-19 patients demonstrate heterogeneous profile of acute vascular injury, inflammation and age-linked chronic brain diseases

Abstract:

Background: This study examined neuropathological findings of patients who died following hospitalization in an intensive care unit with SARS-CoV-2.

Methods: Data originate from 20 decedents who underwent brain autopsy followed by ex-vivo imaging and dissection. Systematic neuropathologic examinations were performed to assess histopathologic changes including cerebrovascular disease and tissue injury, neurodegenerative diseases, and inflammatory response. Cerebrospinal fluid (CSF) and fixed tissues were evaluated for the presence of viral RNA and protein.

Results: The mean age-at-death was 66.2 years (range: 26-97 years) and 14 were male. The patient’s medical history included cardiovascular risk factors or diseases (n = 11, 55%) and dementia (n = 5, 25%). Brain examination revealed a range of acute and chronic pathologies. Acute vascular pathologic changes were common in 16 (80%) subjects and included infarctions (n = 11, 55%) followed by acute hypoxic/ischemic injury (n = 9, 45%) and hemorrhages (n = 7, 35%). These acute pathologic changes were identified in both younger and older groups and those with and without vascular risk factors or diseases. Moderate-to-severe microglial activation were noted in 16 (80%) brains, while moderate-to-severe T lymphocyte accumulation was present in 5 (25%) brains. Encephalitis-like changes included lymphocytic cuffing (n = 6, 30%) and neuronophagia or microglial nodule (most prominent in the brainstem, n = 6, 30%) were also observed. A single brain showed vasculitis-like changes and one other exhibited foci of necrosis with ball-ring hemorrhages reminiscent of acute hemorrhagic leukoencephalopathy changes. Chronic pathologies were identified in only older decedents: 7 brains exhibited neurodegenerative diseases and 8 brains showed vascular disease pathologies. CSF and brain samples did not show evidence of viral RNA or protein.

Conclusions: Acute tissue injuries and microglial activation were the most common abnormalities in COVID-19 brains. Focal evidence of encephalitis-like changes was noted despite the lack of detectable virus. The majority of older subjects showed age-related brain pathologies even in the absence of known neurologic disease. Findings of this study suggest that acute brain injury superimposed on common pre-existing brain disease may put older subjects at higher risk of post-COVID neurologic sequelae.

Source: Agrawal S, Farfel JM, Arfanakis K, Al-Harthi L, Shull T, Teppen TL, Evia AM, Patel MB, Ely EW, Leurgans SE, Bennett DA, Mehta R, Schneider JA. Brain autopsies of critically ill COVID-19 patients demonstrate heterogeneous profile of acute vascular injury, inflammation and age-linked chronic brain diseases. Acta Neuropathol Commun. 2022 Dec 17;10(1):186. doi: 10.1186/s40478-022-01493-7. PMID: 36528671; PMCID: PMC9758667. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9758667/ (Full text)

Cytokine Profiles Associated With Acute COVID-19 and Long COVID-19 Syndrome

Abstract:

The duration and severity of COVID-19 are related to age, comorbidities, and cytokine synthesis. This study evaluated the impact of these factors on patients with clinical presentations of COVID-19 in a Brazilian cohort.

A total of 317 patients diagnosed with COVID-19 were included; cases were distributed according to clinical status as severe (n=91), moderate (n=56) and mild (n=170). Of these patients, 92 had acute COVID-19 at sample collection, 90 had already recovered from COVID-19 without sequelae, and 135 had sequelae (long COVID syndrome).

In the acute COVID-19 group, patients with the severe form had higher IL-6 levels (p=0.0260). In the post-COVID-19 group, there was no significant difference in cytokine levels between groups with different clinical conditions. In the acute COVID-19 group, younger patients had higher levels of TNF-α, and patients without comorbidities had higher levels of TNF-α, IL-4 and IL-2 (p<0.05). In contrast, patients over age 60 with comorbidities had higher levels of IL-6. In the post-COVID-19 group, subjects with long COVID-19 had higher levels of IL-17 and IL-2 (p<0.05), and subjects without sequelae had higher levels of IL-10, IL-6 and IL- 4 (p<0.05).

Our results suggest that advanced age, comorbidities and elevated serum IL-6 levels are associated with severe COVID-19 and are good markers to differentiate severe from mild cases. Furthermore, high serum levels of IL-17 and IL-2 and low levels of IL-4 and IL-10 appear to constitute a cytokine profile of long COVID-19, and these markers are potential targets for COVID-19 treatment and prevention strategies.

Source: Queiroz MAF, Neves PFMD, Lima SS, Lopes JDC, Torres MKDS, Vallinoto IMVC, Bichara CDA, Dos Santos EF, de Brito MTFM, da Silva ALS, Leite MM, da Costa FP, Viana MNDSA, Rodrigues FBB, de Sarges KML, Cantanhede MHD, da Silva R, Bichara CNC, van den Berg AVS, Veríssimo AOL, Carvalho MDS, Henriques DF, Dos Santos CP, Nunes JAL, Costa IB, Viana GMR, Carneiro FRO, Palacios VRDCM, Quaresma JAS, Brasil-Costa I, Dos Santos EJM, Falcão LFM, Vallinoto ACR. Cytokine Profiles Associated With Acute COVID-19 and Long COVID-19 Syndrome. Front Cell Infect Microbiol. 2022 Jun 30;12:922422. doi: 10.3389/fcimb.2022.922422. PMID: 35846757; PMCID: PMC9279918. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9279918/ (Full text)