Summary
| Direction in PACVS | ↑ Elevated — higher than in the comparison group |
|---|---|
| Category | Inflammatory |
| Also described as | Pro-inflammatory cytokine |
| Compared against | HC (healthy controls) |
| Associated symptoms | Elevated in >80% of PACVS registry cohort |
| Test type | Blood test (serum / plasma / whole blood) |
| LOINC code | 26881-5 |
| Source | Mundorf et al. 2024 — doi:10.3390/vaccines12070790 |
| Condition atlas | PACVS Biomarker Atlas |
Other conditions where Interleukin-6 (IL-6) is reported
- Interleukin-6 (IL-6) in Gulf War Illness — ↑ elevated vs HGV
- Interleukin-6 (IL-6) in Long COVID — ↑ elevated vs HC, R
- IL-6 in Low Back Pain — ↑ elevated vs chronic nonspecific LBP vs asymptomatic controls
- Interleukin-6 (IL-6) in Lyme Disease — ↑ elevated vs HC
- IL-6 in Major Depressive Disorder — ↑ elevated vs females with depression vs healthy female controls
- Interleukin-6 (IL-6) in ME/CFS — ↕ inconsistent vs HC
- IL-6 in Rheumatoid Arthritis — ↑ elevated vs RA vs healthy (established inflammatory pathway/drug target)
See the cross-condition hub: Interleukin-6 (IL-6) across conditions.
Trials, interventions and tests
Commercial test availability
Interleukin-6 (IL-6), Serum — commercial laboratory test.
Links are for reference only; availability, specimen requirements and coverage vary by location.
Related Inflammatory markers in PACVS
- IL-8 ↑
Full list: PACVS Biomarker Atlas.
Frequently asked questions
Is IL-6 high or low in PACVS?
Elevated. Studies summarised in the OSMF atlas report higher IL-6 in PACVS than in healthy controls. Source: Mundorf et al. 2024.
What symptoms is IL-6 associated with in PACVS?
The cited literature associates this marker with Elevated in >80% of PACVS registry cohort. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures IL-6?
It is measured as a blood test (serum / plasma / whole blood). The standard laboratory code is LOINC 26881-5. Commercial laboratories such as Quest Diagnostics, LabCorp, Ulta Lab Tests list an orderable assay.
Is one abnormal IL-6 result diagnostic of PACVS?
No. No single biomarker is diagnostic of PACVS. IL-6 findings come from group comparisons, overlap considerably between patients and controls, and vary with study design, timing and comparison group. A result should be interpreted by a clinician alongside symptoms, history and other tests.
Is IL-6 specific to PACVS?
No. The same marker is also reported in Gulf War Illness, Long COVID, Low Back Pain, Lyme Disease, ME/CFS, Major Depressive Disorder, Rheumatoid Arthritis in this atlas, so it reflects shared biology (for example inflammation or vascular stress) rather than a condition-specific signature.
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Last reviewed: 2026-06-30 · Page generated from pacvs.json · Browse: PACVS atlas · Biomarker Index · All marker pages
Disclaimer: This page is an educational synthesis of published, peer-reviewed research and is not medical advice. Biomarker findings vary across studies with case definitions, comparison groups, timing and assay methods. Direction of change reflects the predominant finding in the cited source and does not establish a diagnostic threshold. Discuss any test result with a qualified clinician.