Post-acute infectious syndromes (PAIS) and myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) are complex systemic diseases whose diagnosis remains highly challenging due to the lack of reliable biomarkers and limited healthcare resources. A broad differential diagnostic assessment is therefore still required to exclude other diseases with overlapping symptoms or to identify potential comorbidities. 

A variety of potential pathomechanisms are currently being discussed and investigated. These include alterations in the biomechanical properties of blood cells, changes in the cellular and humoral immune status, vascular abnormalities and dysregulation of multiple components of the nervous system. Comparative analysis of these processes in patients with PAIS and/or ME/CFS and healthy controls may improve the understanding of disease mechanisms, facilitate more objective diagnostic procedures, and support the development of novel therapeutic approaches.

The HelP study, coordinated at the Munich Chronic Fatigue Center (MCFC), aims to recruit a cohort of healthy children, adolescents and young adults up to 25 years of age and to assess them using a range of established and innovative diagnostic methods. This approach will enable age-matched comparative analyses between patients and healthy individuals and may contribute to the identification of potential biomarkers and novel therapeutic targets for PAIS and ME/CFS.