Novel Clinical, Immunological, and Metabolic Features Associated with Persistent Post-Acute COVID-19 Syndrome

Area of Science:

• Immunology
• Metabolomics
• Infectious Diseases

Background:

• Post-acute COVID-19 syndrome (PACS), or long COVID-19, presents persistent symptoms after initial infection.
• While some risk factors are known, the underlying mechanisms of PACS remain unclear.
• Early identification of individuals at risk for PACS is essential for timely intervention.

Purpose of the Study:

• To investigate clinical, immunological, and metabolomic risk factors associated with PACS development.
• To identify potential biomarkers for predicting long COVID-19 in patients.

Main Methods:

• Analysis of 51 COVID-19 survivors 7-19 months post-infection.
• Assessment of clinical, immunological (e.g., LDGs, IL-8, lymphocytes, monocytes), and metabolomic profiles during acute infection and at follow-up.
• Multivariate analysis to identify predictive markers.

Main Results:

• 37.2% of patients met PACS criteria at follow-up.
• PACS patients showed elevated baseline levels of mature low-density granulocytes (LDGs), interleukin-8 (IL-8), pyruvate, pseudouridine, and cystine.
• Key predictors included elevated baseline pyruvate and decreased alpha tocopherol, with follow-up changes in B lymphocytes, monocytes, and 3-hydroxyisovaleric acid.

Conclusions:

• Specific immunological and metabolomic profiles during acute COVID-19 infection are associated with PACS development.
• Elevated pyruvate and IL-8, along with altered granulocyte and monocyte counts, may indicate higher risk for long COVID-19.
• These findings support the use of early biomarkers for identifying patients prone to persistent post-COVID-19 symptoms.