This tool is designed to assess the likelihood of a thyroid storm based on specific clinical criteria. Users select from a set of six potential symptoms or clinical findings, and the tool applies diagnostic rules to determine the likelihood of a thyroid storm. The output can indicate one of three possibilities: "Definite thyroid storm," "Suspected thyroid storm," or "Criteria for thyroid storm not met." 

Here's how it works:

- Inputs: Users can choose from the following six clinical findings:
  - Elevated levels of free triiodothyronine or free thyroxine
  - Central nervous system manifestations, such as restlessness, delirium, mental aberration/psychosis, somnolence/lethargy, or coma
  - Fever, with a temperature of 38 degrees Celsius or higher
  - Tachycardia, with a heart rate of 130 beats per minute or higher
  - Congestive heart failure, such as pulmonary edema, rales, or cardiogenic shock
  - Gastro-hepatic manifestations, including nausea, vomiting, diarrhea, or a bilirubin level of 3.0 mg/dL or higher

The computation assesses these inputs against diagnostic criteria:

1. Definite thyroid storm:
   - Requires elevated hormone levels and central nervous system manifestations, plus at least one of these additional symptoms: fever, tachycardia, congestive heart failure, or gastro-hepatic manifestations.
   - Alternatively, having elevated hormone levels with any combination of three other symptoms also indicates a definite thyroid storm.

2. Suspected thyroid storm:
   - Occurs when elevated hormone levels are present along with any two other symptoms from the list.
   - Alternatively, central nervous system manifestations with any additional symptom suggest a suspected storm.
   - Another scenario is having elevated hormone levels with any triple combination of symptoms from the list. 

If none of these criteria combinations are met, the tool outputs "Criteria for thyroid storm not met."

This method helps clinicians systematically evaluate symptoms for a conclusive diagnosis of thyroid storm, ensuring that significant combinations of criteria are identified and properly interpreted.

The Diagnostic Criteria for Thyroid Storm calculator, developed by the Japan Thyroid Association, is a clinical tool used to diagnose thyroid storm, a life-threatening condition characterized by severe manifestations of thyrotoxicosis. This calculator is applicable to patients presenting with symptoms suggestive of a thyroid storm, such as fever, tachycardia, altered mental status, and gastrointestinal/hepatic disturbances.

The clinical utility of this calculator lies in its ability to stratify patients into categories of 'Definitive', 'Suspected', or 'No thyroid storm', based on the severity and number of clinical and biochemical manifestations. This helps clinicians to promptly identify and manage this critical condition, thereby reducing the associated morbidity and mortality.

There are no specific exclusion criteria for the use of this calculator. However, it should be noted that the diagnosis of thyroid storm is a clinical one, and this calculator should be used in conjunction with a comprehensive clinical assessment. It may not be applicable in patients with non-thyroidal illnesses that can mimic the symptoms of a thyroid storm.

Diagnostic Criteria for Thyroid Storm (Japan Thyroid Association)