JTA Criteria (Thyroid Storm, TS1 and TS2)
The Japan Thyroid Association (JTA) diagnostic criteria for thyroid storm (Akamizu and colleagues 2012).
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Example
- Thyrotoxicosis
- confirmed
- Clinical evidence of thyroid disease
- Yes
- CNS manifestation
- Yes
- Fever of 38 degrees C or higher
- Yes
- Heart rate of 130 beats per minute or more
- No
- Congestive heart failure at a severe level
- No
- Gastrointestinal or hepatic disturbance
- No
- Whether an alternative cause of the findings has been considered and excluded
- Yes
Result: TS1
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What the result means
- Prerequisite
- THYROTOXICOSIS (elevated free T3 or T4). Not a scored item - without it neither grade can be met.
- TS1
- Thyrotoxicosis + a CNS manifestation + at least ONE other feature, OR thyrotoxicosis + at least THREE other features. DEFINITE.
- TS2
- Thyrotoxicosis + at least TWO other features, OR the TS1 pattern with thyroid function tests unavailable. SUSPECTED.
- CNS privilege
- CNS manifestations are PRIVILEGED and nothing else is. Fever + tachycardia alone = TS2; delirium + fever alone = TS1.
- Grades
- DEFINITE vs SUSPECTED - diagnostic CERTAINTY, not severity. A TS2 patient is not less sick.
- No-labs route
- The same clinical picture drops a grade purely on whether a blood test has come back.
- Thresholds
- Fever 38 C or higher; heart rate 130 or more; bilirubin 3.0 mg/dL or more; GCS 14 or below.
- Heart failure
- SEVERE LEVEL ONLY: pulmonary edema, rales over half the lung fields, or cardiogenic shock (NYHA IV / Killip III+).
- Exclusion
- DELIBERATELY NOT MECHANICAL - the conditions that would explain the findings may themselves TRIGGER storm.
- vs BWPS
- Burch-Wartofsky is a POINT SCALE; these are COMBINATION RULES. They disagree, and a total cannot be converted to a grade.
- Scope
- Classifies, does not treat. FAILING THESE DOES NOT EXCLUDE thyroid storm; do not wait on labs to treat.
What you enter
- Thyrotoxicosis (elevated free T3 or free T4).
- Clinical evidence of thyroid disease (history, goiter, exophthalmos).
- CNS manifestation - THE PRIVILEGED FEATURE.
- Fever of 38 degrees C or higher.
- Heart rate of 130 beats per minute or more.
- Congestive heart failure at a severe level.
- Gastrointestinal or hepatic disturbance.
- Whether an alternative cause of the findings has been considered and excluded.
Full field descriptions
- Thyrotoxicosis (elevated free T3 or free T4). A PREREQUISITE, not a scored item: "absent" means neither grade can be met. "labs-unavailable" opens the TS2 no-laboratory route.
- Clinical evidence of thyroid disease (history, goiter, exophthalmos). Used ONLY for the TS2 no-laboratory route.
- CNS manifestation - THE PRIVILEGED FEATURE. Restlessness, delirium, mental aberration or psychosis, somnolence or lethargy, convulsion, or coma - equivalently a Glasgow Coma Scale of 14 or below, or a Japan Coma Scale of 1 or above. With it, 1 other feature reaches TS1; without it, 3 are required.
- Fever of 38 degrees C or higher. One of the four non-privileged features.
- Heart rate of 130 beats per minute or more. One of the four non-privileged features.
- Congestive heart failure at a severe level. One of the four non-privileged features. Pulmonary edema, moist rales over more than half the lung fields, or cardiogenic shock - New York Heart Association class IV or Killip class III or above. NOT any heart failure.
- Gastrointestinal or hepatic disturbance. One of the four non-privileged features. Nausea, vomiting, diarrhea, or a total bilirubin of 3 mg/dL or more.
- Whether an alternative cause of the findings has been considered and excluded. REPORTED, NOT DECIDED: the source notes those same conditions may themselves trigger thyroid storm.
How this is calculated
Akamizu T, Satoh T, Isozaki O, et al. Diagnostic criteria, clinical features, and incidence of thyroid storm based on nationwide surveys. Thyroid. 2012;22(7):661-679. Read the source ↗
A reference and educational tool. Not medical, legal, or financial advice, and not a substitute for clinician judgment.