E1 ReplicatedModerate confidencePEM ?ObservationalPeer-reviewedReviewed
Standard · 3 min

Cytokine signature associated with disease severity in chronic fatigue syndrome patients

Jose G. Montoya, Tyson H. Holmes, Jill N. Anderson et al. · Proceedings of the National Academy of Sciences (PNAS) · 2017 · DOI

Quick Summary

Stanford researchers measured 51 cytokines in 192 ME/CFS patients and 392 healthy controls. Seventeen cytokines were significantly elevated in ME/CFS, with TGF-beta most strongly associated with disease severity. More severe patients had higher cytokine levels, suggesting immune activation scales with illness burden.

Why It Matters

This is one of the largest cytokine studies in ME/CFS and provides strong evidence for immune dysregulation correlated with symptom severity. The dose-response relationship between cytokine levels and severity strengthens the biological case for immune involvement.

What This Study Does Not Prove

Elevated cytokines are a feature of many inflammatory conditions. This study cannot show whether cytokine dysregulation causes ME/CFS or is a secondary response to the illness.

Topics

Tags

Method Flag:PEM_UNCLEARFUKUDA_CRITERIABIOLOGICALLY_RELEVANTExploratory OnlyWeak Case Definition
Symptom:Fatigue
Biomarker:CytokinesBlood Biomarker

Metadata

DOI
10.1073/pnas.1710519114
Case definition
Fukuda 1994 Criteria
Sample size
192 patients
Control group
Yes
Review status
Editor reviewed
Evidence level
Replicated human evidence from multiple independent studies
Last updated
7 April 2026