Summary
| Direction in Gulf War Illness | ↕ Inconsistent — reported as both higher and lower across studies, with no consistent direction |
|---|---|
| Category | Neurological |
| Also described as | Astrocyte protein |
| Compared against | HGV (healthy Gulf War veteran controls) |
| Associated symptoms | Neurological symptoms subset |
| Test type | Blood test (serum / plasma / whole blood) |
| Source | Gean et al. 2021 — doi:10.1016/j.lfs.2021.119456 |
| Condition atlas | Gulf War Illness Biomarker Atlas |
Other conditions where S100B is reported
- S100B in Epilepsy — ↑ elevated vs epileptic patients vs healthy controls
- S100B in Long COVID — ↑ elevated vs HC
See the cross-condition hub: S100B across conditions.
Related Neurological markers in Gulf War Illness
Full list: Gulf War Illness Biomarker Atlas.
Frequently asked questions
Is S100B high or low in Gulf War Illness?
Mixed. Some studies report higher and others lower S100B in Gulf War Illness compared with healthy Gulf War veteran controls, so no single direction is established. Source: Gean et al. 2021.
What symptoms is S100B associated with in Gulf War Illness?
The cited literature associates this marker with Neurological symptoms subset. These are population-level associations and do not mean the marker causes the symptoms.
Which test measures S100B?
It is measured as a blood test (serum / plasma / whole blood). Many of the cited studies used research-grade assays, so clinical availability may vary.
Is one abnormal S100B result diagnostic of Gulf War Illness?
No. No single biomarker is diagnostic of Gulf War Illness. S100B 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 S100B specific to Gulf War Illness?
No. The same marker is also reported in Epilepsy, Long COVID 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: 2026-06-29 · Page generated from gulf-war-illness.json · Browse: Gulf War Illness 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.