[Long COVID - neurological or somatoform disease?].

Observed Findings

• Three main theoretical frameworks for long COVID pathomechanism are documented in the literature: neurological, systemic, and psychoneuroimmunological models.
• Long COVID shares significant clinical overlap with ME/CFS, Gulf War syndrome, chronic Lyme disease, and somatic symptom disorder.
• No reproducible, disease-specific biomarker has been identified for long COVID despite intensive research.
• The most common long COVID symptoms are fatigue, diffuse pain, post-exertional malaise, and cognitive impairment (brain fog).
• Long COVID is defined as persistent symptoms lasting at least 2 months following confirmed or suspected SARS-CoV-2 infection.

Inferred Conclusions

• Long COVID pathomechanism remains unknown, likely involving complex interactions between direct viral effects, immune dysregulation, and central sensitization.
• The nonspecific symptom profile and diagnostic uncertainty in long COVID parallels longstanding challenges in ME/CFS diagnosis and classification.
• Elucidating long COVID's true etiology is essential for developing appropriate, evidence-based therapeutic interventions.
• The absence of disease-specific biomarkers suggests that current diagnostic frameworks may be inadequate and that novel research approaches are needed.

Remaining Questions