Peer-Reviewed Literature Synthesis

ME/CFS Biomarker Atlas

Molecular, metabolic, immunological, and autonomic alterations in myalgic encephalomyelitis / chronic fatigue syndrome (ME/CFS) compared to healthy sedentary and active controls — including post-exertional malaise (PEM) phenotypes.

Literature Overview

Synthesized from systematic reviews and meta-analyses through 2024. ME/CFS lacks a validated single biomarker; multi-system dysfunction across immune signaling, mitochondrial metabolism, and autonomic regulation is the dominant research paradigm.

92
Studies in cytokine review
22
Urinary biomarker studies
13
Acylcarnitine studies
24
HRV studies meta-analyzed

Immune & Inflammatory Signaling

Low-grade immune activation with inconsistent cytokine directions across studies. Meta-analyses identify IL-1 and TGF-β as most consistently elevated; TNF-α and IL-6 show heterogeneous results.

  • RNase L pathway dysregulation
  • NK cell cytotoxicity reduction
  • CD8+ T cell functional impairment

Mitochondrial & Metabolic Dysfunction

Impaired oxidative phosphorylation, elevated acylcarnitines, and reduced ATP production — consistent with cellular energy deficit underlying PEM and exercise intolerance.

  • Elevated C16 & C18 acylcarnitines
  • Reduced ATP resynthesis post-exercise
  • Altered amino acid metabolism

Autonomic & Neuroimmune Dysregulation

Reduced heart rate variability, orthostatic intolerance, and GPCR autoantibodies overlap with dysautonomia phenotypes seen in Long COVID and PACVS.

  • Reduced HRV (time & frequency domain)
  • β-adrenergic & muscarinic autoantibodies
  • Altered cortisol rhythm

Searchable Alterations Database

Filter by category. HC = healthy controls; PEM = post-exertional malaise challenge. Markers tagged "LC overlap" are also reported in long COVID with ME/CFS phenotype.

Overlap with Long COVID & PACVS

ME/CFS criteria are met by a substantial subset of long COVID patients. Metabolic (serine, sarcosine, ceramides), autonomic (HRV, POTS), and GPCR autoantibody findings are shared across conditions. See the Long COVID Biomarker Atlas and PACVS Biomarker Atlas for infection- and vaccination-specific markers.

PEM timing matters

Many metabolic and immune biomarkers are measured at baseline in ME/CFS cohorts, but PEM — the hallmark symptom — may only be captured after standardized exertion challenge (e.g., 2-day CPET). Acylcarnitine elevations and lactate abnormalities may be more pronounced post-exercise than at rest (Holden et al., 2020; Jinushi et al., 2023).

Marker / MetaboliteDirectionCategoryvs. ComparisonAssociated SymptomsKey Reference

Category Deep Dives

🔥 Cytokines & Inflammatory Mediators

  • IL-1 (IL-1α/β)↑ meta-analysis
  • TGF-β↑ meta-analysis
  • TNF-α↕ heterogeneous
  • IL-6↕ heterogeneous
  • IL-8 / CXCL8↕ variable
  • CRP↕ low-grade
  • Leptin↑ inflammatory proteins

⚡ Mitochondrial & Energy Metabolism

  • Acylcarnitines (C16, C18)↑ meta-analysis
  • ATP production capacity↓ PEM
  • Lactate (rest & exercise)↑
  • Pyruvate dehydrogenase activity↓
  • Mitochondrial membrane potential↓
  • 2-day CPET VO₂ decline↓ day 2

🛡️ Immune Cell Function

  • NK cell cytotoxicity↓
  • CD8+ T cell perforin↓
  • RNase L (37-kDa fragment)↑ dysregulated
  • Neutrophil elastase↑
  • CD26 / sCD26 (DPPIV)↕ altered

💓 Autonomic & Cardiovascular

  • Heart rate variability (RMSSD)↓ meta-analysis
  • LF/HF ratio↕ altered
  • Orthostatic HR increment↑ POTS
  • Blood pressure variability↑
  • Baroreflex sensitivity↓

🧠 Neurological & Autoimmune

  • β2-adrenergic receptor autoantibodies↑
  • Muscarinic cholinergic autoantibodies↑
  • Neurofilament light chain (NfL)↕ subset
  • Cortisol (flattened diurnal)↕ HPA axis

🧪 Urinary & Metabolomic Signatures

  • Urinary metabolite panelDiscriminant
  • Creatinine-normalized metabolitesAltered
  • Serine / sarcosine (plasma)↓ LC overlap
  • Kynurenine pathway↑
  • Tryptophan / benzoate metabolites↕ BioMapAI 2025
  • Branched-chain amino acids (BCAAs)↕ BioMapAI 2025
  • Bile acids (plasma)↕ BioMapAI 2025

🔬 Multi-Omics & Immune Profiling

  • MAIT cell activation (IFN-γ / GzA)↑ BioMapAI 2025
  • γδT cell frequency / activation↑ BioMapAI 2025
  • Short-chain fatty acids (gut)↕ microbiome axis
  • PBMC electrical impedance↑ nanoneedle 100%
  • PBMC Raman spectroscopic fingerprintDiscriminant 91%

🧬 Genomic / Epigenetic

  • EpiSwitch 200-CC panelDiagnostic 96% acc.
  • Circulating miRNA (11-panel)Discriminant classifier
  • IL-2 / JAK-STAT pathway CCs↕ EpiSwitch 2025
  • TLR signalling CCs↕ EpiSwitch 2025

Key References

Systematic Review

Biomarkers for diagnosing ME/CFS: a systematic review

Maksoud R et al. BMC Med. 2023;21:232
DOI: 10.1186/s12916-023-02893-9 →
Meta-Analysis — Cytokines

Cytokine aberrations in ME/CFS: a systematic review and meta-analysis

Corbitt M et al. Psychoneuroendocrinology. 2019;107:57–64
DOI: 10.1016/j.psyneuen.2019.05.008 →
Meta-Analysis — Inflammatory Proteins

Inflammatory proteins are altered in ME/CFS: a systematic review and meta-analysis

Strawbridge R et al. Psychoneuroendocrinology. 2019;108:57–68
DOI: 10.1016/j.psyneuen.2019.06.019 →
Meta-Analysis — Acylcarnitines

Acylcarnitine alteration in ME/CFS: a systematic review and meta-analysis

Jinushi E et al. J Transl Med. 2023;21:444
DOI: 10.1186/s12967-023-04347-4 →
Meta-Analysis — HRV

Autonomic function in ME/CFS: a systematic review and meta-analysis

Nelson MJ et al. J Transl Med. 2019;17:370
DOI: 10.1186/s12967-019-02100-4 →
Meta-Analysis — Urinary

Urinary biomarkers in ME/CFS: a systematic review and meta-analysis

Taccori S et al. J Transl Med. 2023;21:505
DOI: 10.1186/s12967-023-04398-7 →
Systematic Review — Mitochondria

Mitochondrial abnormalities in ME/CFS

Holden S et al. J Transl Med. 2020;18:290
DOI: 10.1186/s12967-020-02477-4 →
Primary Study — Long COVID overlap

Metabolomic and Immune Alterations in Long COVID Patients with ME/CFS

Saito S et al. Front Immunol. 2024;15:1341843
DOI: 10.3389/fimmu.2024.1341843 →
Multi-Omics ML — BioMapAI

AI-driven multi-omics modeling of ME/CFS (BioMapAI)

Xiong R, Oh J, Unutmaz D et al. Nat Med. 2025 (Jackson Laboratory)
DOI: 10.1038/s41591-025-03788-3 →
Diagnostic Platform — Nanoneedle

A nanoelectronics-blood-based diagnostic biomarker for ME/CFS

Esfandyarpour R et al. PNAS. 2019;116(21):10250–10257 (Ron Davis lab, Stanford)
DOI: 10.1073/pnas.1901274116 →
Genomic — Circulating miRNA

Identification of circulating microRNA signatures in ME/CFS and fibromyalgia

Nepotchatykh E et al. Sci Rep. 2023;13:1896 (Moreau lab, Montréal)
DOI: 10.1038/s41598-023-28786-8 →
Genomic — EpiSwitch

EpiSwitch chromosomal conformation signatures for ME/CFS diagnosis (EPI-ME)

Pshezhetskiy D et al. J Transl Med. 2025 (Oxford BioDynamics / UEA). Sensitivity 92%, Specificity 98%
DOI: 10.1186/s12967-025-06341-x →
Diagnostic Platform — Raman Spectroscopy

Raman spectroscopic fingerprint of PBMCs for ME/CFS diagnosis

Morten K et al. University of Oxford. 2023. Accuracy ~91% (ME/CFS vs HC); severity classification 84%
ME Association →
Disclaimer: Educational synthesis only — not medical advice. ME/CFS biomarker findings vary by diagnostic criteria (Fukuda, Canadian, IOM/SEID, ICC), illness duration, and comparison group. No biomarker is validated as a standalone diagnostic test. Consult qualified healthcare providers for clinical interpretation.