Where Interleukin-6 (IL-6) is reported
Also listed as: IL-6; Pro-inflammatory cytokine
| Condition | Direction | Compared against | Associated symptoms | Source |
|---|---|---|---|---|
| Gulf War Illness | ↑ elevated | healthy Gulf War veteran controls | Systemic inflammation | Johnson et al. 2016 |
| Long COVID | ↑ elevated | healthy controls, recovered individuals without persistent symptoms | Fatigue, systemic inflammation | Lai et al. 2023 |
| Low Back Pain | ↑ elevated | chronic nonspecific LBP vs asymptomatic controls | — | Injeyan et al. 2025 |
| Lyme Disease | ↑ elevated | healthy controls | Active Borrelia infection | Lantos et al. 2021 |
| Major Depressive Disorder | ↑ elevated | females with depression vs healthy female controls | — | Jarkas et al. 2024 |
| ME/CFS | ↕ inconsistent | healthy controls | Systemic inflammation, variable | Corbitt et al. 2019 |
| PACVS | ↑ elevated | healthy controls | Elevated in >80% of PACVS registry cohort | Mundorf et al. 2024 |
| Rheumatoid Arthritis | ↑ elevated | RA vs healthy (established inflammatory pathway/drug target) | — | Qin et al. 2022 |
Frequently asked questions
In which conditions is Interleukin-6 (IL-6) altered?
In the OSMF atlas Interleukin-6 (IL-6) is reported in Gulf War Illness, Long COVID, Low Back Pain, Lyme Disease, ME/CFS, Major Depressive Disorder, PACVS, Rheumatoid Arthritis. It is elevated in 7, mixed in 1 across 8 entries.
Does Interleukin-6 (IL-6) point to one specific diagnosis?
No. Because Interleukin-6 (IL-6) changes in several conditions (Gulf War Illness, Long COVID, Low Back Pain, Lyme Disease, ME/CFS, Major Depressive Disorder, PACVS, Rheumatoid Arthritis), an abnormal result cannot identify which condition, if any, is present. It must be interpreted with symptoms, history and other tests.
What is the LOINC code for Interleukin-6 (IL-6)?
Entries in this atlas use LOINC 26881-5. LOINC codes identify the laboratory observation so results can be compared across systems.
Is one abnormal Interleukin-6 (IL-6) result diagnostic?
No single biomarker result is diagnostic of any of these conditions. Findings reflect group averages from published cohorts with substantial overlap between patients and controls.
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Last reviewed: 2026-07-03 · Browse: Biomarker Index · All marker pages · Biomarker Atlas
Disclaimer: Educational synthesis of peer-reviewed research; not medical advice. Findings are group-level and vary with study design. Discuss any result with a qualified clinician.