To introduce a Special Issue presenting multidisciplinary research on the biomedical features, assessment, and treatment of Long COVID (PASC).
Approach:
Pulmonary imaging: The editorial summarizes studies linking CT patterns after severe COVID-19 ARDS with dyspnoea and reduced forced vital capacity, and comparing ultra-low-dose with standard-dose CT for detecting persistent lung abnormalities.
Carotid body morphology: It describes a retrospective CT angiography study of carotid body size in patients previously hospitalized with COVID-19 pneumonia.
Serological biomarkers: It reviews serological findings in 275 patients with Omicron-related Long COVID, including associations with disease severity, brain fog, and quality of life.
Microbiota-directed treatment: It summarizes a randomized, double-blind, placebo-controlled trial of four weeks of probiotic supplementation.
Key Findings:
Reticulations or septal thickening were positively correlated with symptomatic dyspnoea; parenchymal or atelectatic bands were associated with reduced forced vital capacity.
Ultra-low-dose CT had 95.0% diagnostic accuracy for persistent lung abnormalities, increasing to 98% among non-obese subjects.
Carotid bodies were significantly enlarged in patients previously hospitalized for COVID-19 pneumonia.
Among patients with Omicron-related Long COVID, nucleocapsid N-antibody titers were positively associated with acute disease severity and antiviral immune responses; lower spike S-antibody titers were correlated with memory impairment and poorer quality of lif…
Probiotic supplementation was associated with a larger decrease in clinically relevant fatigue scores than placebo over four weeks (24.24% versus 6.06%), alongside changes in gut microbial taxa, metabolites, and immune-related pathways.
Interpretation:
The editorial presents Long COVID as a complex, multisystem condition that cannot be understood through a single disciplinary lens. It notes that the mechanisms remain uncertain and that vaccination status and time since infection matter when interpreting serological profiles.
Limitations:
The probiotic trial had a limited sample size.
The editorial notes that considerable uncertainty persists about the causes of Long COVID.
Serological findings require consideration of vaccination status and time since infection.
Conclusion:
The editorial calls for continued research combining imaging, immunological, physiological, and microbiome-related approaches to characterize, monitor, and treat Long COVID.
