Possible reasons for post-exertional malaise () in people with and/or
Muscle biopsy of 11 people with Long COVID and PEM showed:
Microvascular abnormalities
Fewer capillaries
Increased macrophages
Gene signatures w/immune dysregulation and altered metabolic pathways.
Hypothesis: Initial viral infection caused immune-mediated structural changes of the microvasculature, potentially explaining the exercise-dependent fatigue and muscle pain.
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