Tag: anemia

Iron dysregulation and inflammatory stress erythropoiesis associates with long-term outcome of COVID-19

Abstract:

Persistent symptoms following SARS-CoV-2 infection are increasingly reported, although the drivers of post-acute sequelae (PASC) of COVID-19 are unclear. Here we assessed 214 individuals infected with SARS-CoV-2, with varying disease severity, for one year from COVID-19 symptom onset to determine the early correlates of PASC.

A multivariate signature detected beyond two weeks of disease, encompassing unresolving inflammation, anemia, low serum iron, altered iron-homeostasis gene expression and emerging stress erythropoiesis; differentiated those who reported PASC months later, irrespective of COVID-19 severity. A whole-blood heme-metabolism signature, enriched in hospitalized patients at month 1-3 post onset, coincided with pronounced iron-deficient reticulocytosis. Lymphopenia and low numbers of dendritic cells persisted in those with PASC, and single-cell analysis reported iron maldistribution, suggesting monocyte iron loading and increased iron demand in proliferating lymphocytes.

Thus, defects in iron homeostasis, dysregulated erythropoiesis and immune dysfunction due to COVID-19 possibly contribute to inefficient oxygen transport, inflammatory disequilibrium and persisting symptomatology, and may be therapeutically tractable.

Source: Hanson AL, Mulè MP, Ruffieux H, Mescia F, Bergamaschi L, Pelly VS, Turner L, Kotagiri P; Cambridge Institute of Therapeutic Immunology and Infectious Disease–National Institute for Health Research (CITIID–NIHR) COVID BioResource Collaboration; Göttgens B, Hess C, Gleadall N, Bradley JR, Nathan JA, Lyons PA, Drakesmith H, Smith KGC. Iron dysregulation and inflammatory stress erythropoiesis associates with long-term outcome of COVID-19. Nat Immunol. 2024 Mar;25(3):471-482. doi: 10.1038/s41590-024-01754-8. Epub 2024 Mar 1. PMID: 38429458; PMCID: PMC10907301. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10907301/ (Full text)

Haematological sequelae in the post-acute phase of symptomatic SARS-CoV-2 infection

Abstract:

Many patients surviving SARS-CoV-2 infection suffer from long-term symptoms (long COVID or post COVID) such as shortness of breath, fatigue, loss of taste or smell and cognitive deterioration. However, few data are available concerning blood cell counts and haematological parameters during the post-COVID period.

We analysed haematological data from 83 patients previously admitted to the internal medicine unit of our institution because of symptomatic SARS-CoV-2 infection; all data were obtained within 1-12 months from disease onset. A control group of 70 apparently healthy, age- and sex-matched COVID-19 negative individuals was assessed for comparison. Blood cell counts improved in the post-COVID period, but 81% of patients had persistent abnormalities, compared with 50% in the control group, p < 0.001.

Most common haematological findings included anaemia (40%), reduced lymphocyte (43%) or eosinophil counts (38%) and low IgM memory B cells and correlated with advanced age, number of chronic comorbidities, female gender, altered renal function, reduced baseline Hb and procalcitonin concentrations and increased RDW. Data on lymphocytes and IgM memory B cells show that impaired immune responses may persist for up to one year in the post-COVID period, possibly contributing to long-term symptoms, especially in female patients.

Source: Bergamaschi G, Barteselli C, Calabretta F, Lenti MV, Merli S, Rossi CM, Di Sabatino A. Haematological sequelae in the post-acute phase of symptomatic SARS-CoV-2 infection. Intern Emerg Med. 2024 Jan;19(1):125-133. doi: 10.1007/s11739-023-03459-6. Epub 2023 Nov 24. PMID: 38001354. https://pubmed.ncbi.nlm.nih.gov/38001354/

Hematological alterations associated with long COVID-19

Abstract:

Long COVID-19 is a condition characterized by persistent symptoms lasting beyond the acute phase of COVID-19. Long COVID-19 produces diverse symptomatology and can impact organs and systems, including the hematological system. Several studies have reported, in COVID-19 patients, hematological abnormalities. Most of these alterations are associated with a higher risk of severe disease and poor outcomes.

This literature review identified studies reporting hematological parameters in individuals with Long COVID-19. Findings suggest that Long COVID-19 is associated with a range of sustained hematological alterations, including alterations in red blood cells, anemia, lymphopenia, and elevated levels of inflammatory markers such as ferritin, D-dimer, and IL-6.

These alterations may contribute to a better understanding of the pathophysiology of Long COVID-19 and its associated symptoms. However, further research is needed to elucidate the underlying mechanisms and potential treatments for these hematological changes in individuals with Long COVID-19.

Source: Lechuga Guilherme C., Giovanni De-Simone Salvatore, Morel Carlos M. Hematological alterations associated with long COVID-19. Frontiers in Physiology, Vol 14, 2023. DOI: 10.3389/fphys.2023.1203472  ISSN: 1664-042X https://www.frontiersin.org/articles/10.3389/fphys.2023.1203472 https://www.frontiersin.org/articles/10.3389/fphys.2023.1203472/full (Full text)

Induction Murine Models of Chronic Fatigue Syndrome by Brucella abortus Antigen Injections: Is Anemia Induced or Not?

Abstract:

To investigate whether Brucella abortus (BA) antigen injections lead to anemia, and to establish an appropriate Chronic Fatigue Syndrome (CFS) animal model by BA injections, 6 repeated injections of BA antigen were fulfilled every 2 weeks. At a high dose of 1∗10(10) particles/mouse, anemia was induced within 2 weeks and then recovered a lot at the end of the research, while at a moderate dose of 1∗10(8) (3 injections) shifting to 1∗10(9)/mouse (3 injections) anemia was absent. In both groups running wheel activity remained very low even 6 weeks after the last injection.

 

Source: Moriya J, He Q, Uenishi H, Akazawa S, Yamakawa J, Kobayashi J, Ishigaki Y. Induction Murine Models of Chronic Fatigue Syndrome by Brucella abortus Antigen Injections: Is Anemia Induced or Not? Biomed Res Int. 2015;2015:191489. doi: 10.1155/2015/191489. Epub 2015 Jun 11. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4480237/ (Full article)