Symptoms and Treatment of Thyroid Storm
Thyroid storm is a life-threatening medical emergency characterized by fever, tachycardia, altered mental status, gastrointestinal symptoms, cardiac arrhythmias, signs of heart failure, and liver dysfunction, requiring immediate treatment with a multi-drug regimen including beta-blockers, thionamides, iodine solutions, and corticosteroids to prevent mortality. 1
Clinical Presentation of Thyroid Storm
Thyroid storm represents an extreme manifestation of thyrotoxicosis with multiorgan decompensation. Key clinical features include:
Cardinal Symptoms
- Fever: Often high-grade
- Tachycardia: Persistent, often out of proportion to fever
- Altered mental status: Ranging from agitation to delirium and coma
- Gastrointestinal dysfunction: Nausea, vomiting, diarrhea
- Cardiovascular manifestations: Arrhythmias, heart failure
- Hepatic dysfunction: Jaundice, elevated liver enzymes 1, 2
Additional Symptoms
- Tremors, nervousness
- Excessive sweating
- Heat intolerance
- Hypertension
- Goiter 3
Diagnosis
The diagnosis of thyroid storm is primarily clinical, as laboratory confirmation may delay critical treatment. Two validated scoring systems can assist in diagnosis:
- Burch-Wartofsky Point Scale: Assesses severity based on temperature, CNS effects, gastrointestinal symptoms, heart rate, heart failure, and precipitating factors
- Japanese Thyroid Association Criteria: Alternative diagnostic framework 1, 2
Laboratory testing should include:
- Serum Free T3, Free T4 (typically elevated)
- TSH (typically suppressed)
- Complete blood count
- Comprehensive metabolic panel 1
Treatment Algorithm
Immediate treatment is essential as mortality can reach 30% even with treatment 1. The treatment approach follows this sequence:
1. Stabilization and Supportive Care
- Airway management
- Fluid resuscitation
- Antipyretics for fever
- Treatment of precipitating factors (infection, trauma, etc.) 1, 2
2. Block Peripheral Effects of Thyroid Hormone
- Beta-blockers: Propranolol is preferred (blocks peripheral conversion of T4 to T3)
3. Block Thyroid Hormone Synthesis
- Thionamides: Should be administered immediately
4. Block Thyroid Hormone Release
- Iodine solutions: Administer 1 hour after thionamides
- Potassium iodide (SSKI) or sodium iodide
- Prevents iodine utilization for new hormone synthesis 1
5. Block T4 to T3 Conversion
- Corticosteroids: Dexamethasone (2 mg IV every 6 hours)
- Reduces T4 to T3 conversion
- Treats potential adrenal insufficiency 1
6. Additional Treatments
- Cholestyramine: Enhances thyroid hormone clearance
- Phenobarbital: For severe agitation
- Cooling measures: For hyperthermia 1, 6
Special Considerations
Pregnancy
- Evaluate fetal status with ultrasound and monitoring
- PTU preferred in first trimester
- Avoid delivery during thyroid storm unless medically necessary 1
Monitoring
- Continuous cardiac monitoring
- Frequent vital sign assessment
- Serial thyroid function tests
- Vigilance for treatment complications 1
Common Pitfalls and Caveats
Delayed diagnosis: Thyroid storm can mimic sepsis, sympathomimetic overdose, alcohol withdrawal, and other conditions 2
Improper sequencing of medications: Administering iodine before thionamides can worsen thyrotoxicosis by providing substrate for hormone synthesis 1
Failure to identify and treat precipitating factors: Common triggers include infection, trauma, surgery, and medication non-compliance 2, 7
Abrupt withdrawal of beta-blockers: Can precipitate exacerbation of hyperthyroidism 4
Overlooking comorbidities: Thyroid storm can co-occur with other endocrine emergencies like diabetic ketoacidosis 8
Early recognition and aggressive treatment are essential to reduce the high mortality associated with thyroid storm. A multidisciplinary approach involving emergency medicine, critical care, and endocrinology is recommended for optimal management.