What are the symptoms of a thyroid storm (hyperthyroid crisis)?

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From the Guidelines

Thyroid storm symptoms include fever, tachycardia, altered mental status, vomiting, diarrhea, and cardiac arrhythmia, and require immediate medical attention to prevent severe morbidity and mortality. These symptoms are associated with a high risk of maternal heart failure, shock, stupor, and coma if left untreated 1. The diagnosis of thyroid storm is based on a combination of signs and symptoms, including fever, tachycardia out of proportion to the fever, altered mental status, and cardiac arrhythmia.

Key Symptoms

  • Fever
  • Tachycardia
  • Altered mental status (nervousness, restlessness, confusion, seizures)
  • Vomiting
  • Diarrhea
  • Cardiac arrhythmia Treatment should not be delayed for test results, and a standard series of drugs, including propylthiouracil or methimazole, saturated solution of potassium iodide or sodium iodide, dexamethasone, and phenobarbital, is used to manage the condition 1. Additionally, beta-blockers, such as propranolol, may be used to treat the increased heart rate and tremor associated with thyrotoxicosis (thyroid storm) or symptomatic hyperthyroidism 1.

Treatment

  • Propylthiouracil or methimazole
  • Saturated solution of potassium iodide or sodium iodide
  • Dexamethasone
  • Phenobarbital
  • Beta-blockers (e.g. propranolol) General supportive measures, such as oxygen, antipyretics, and appropriate monitoring, are also crucial in managing thyroid storm 1. It is essential to identify and treat the underlying cause of the condition, and fetal status should be evaluated in pregnant women 1.

From the Research

Symptoms of Thyroid Storm

The symptoms of thyroid storm, also known as thyrotoxic crisis, include:

  • Fever (>38 degrees C, 100 degrees F) 2
  • Severe tachycardia 2
  • High pulse pressure 2
  • Agitation with tremors 2
  • Flushing 2
  • Sweating 2
  • Heart failure 2
  • Nausea 2
  • Vomiting 2
  • Diarrhea 2
  • Jaundice associated with high free T4 and/or free T3 2
  • Palpitations 3
  • Shortness of breath 3
  • Emesis 3
  • Altered mental status 4

Diagnosis and Treatment

Thyroid storm is a rare but life-threatening condition requiring immediate treatment, preferably in an intensive care unit 5. The diagnosis of a thyrotoxic crisis is made entirely on the clinical findings, and any delay in therapy must be strictly avoided 5. Medical treatment is based on three principles:

  • Counteracting the peripheral effects of thyroid hormones
  • Inhibition of thyroid hormone synthesis
  • Treatment of systemic complications 5 Treatment options include methimazole (MMI) or propylthiouracil (PTU) to block production of thyroid hormones, beta blockers such as propranolol to control the signs and symptoms, and therapeutic plasma exchange (TPE) in certain cases 5, 4, 6.

Mortality Rate

The mortality rate for thyroid storm is significant, ranging from 10-20% 5 to up to 30% if left untreated 4, and can be as high as 75% if therapy is delayed 5.

References

Professional Medical Disclaimer

This information is intended for healthcare professionals. Any medical decision-making should rely on clinical judgment and independently verified information. The content provided herein does not replace professional discretion and should be considered supplementary to established clinical guidelines. Healthcare providers should verify all information against primary literature and current practice standards before application in patient care. Dr.Oracle assumes no liability for clinical decisions based on this content.

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