Thyrotoxic crisis, also called as thyrotoxicosis or Thyroid storm, is an acute, life-threatening condition that is characterized with high levels of thyroid hormones (THs), especially in cases with thyrotoxicosis. It is a hyper-metabolic state that may occur is a first sign of thyrotoxicosis in undiagnosed neonates and children. However, the condition rarely affects children. Untreated thyrotoxic crisis requires immediate diagnosis and aggressive treatment is crucial. The clinical symptoms of thyrotoxic crisis include hypertension, tachycardia,fever, and abnormalities of the neurological and Gastro intestinal systems. Hypertension can be accompanied with congestive heart failure, shock and hypotension. Read on to learn about the symptoms, causes, mechanism and treatment of thyrotoxic crisis:
Common Symptoms of Thyrotoxic Crisis:
- Weight loss and poor feeding habits
- Profuse sweating
- Respiratory distress
- GI symptoms
- Fatigue common in elderly
- Abdominal pain
- Neurologic symptoms
- Altered behavior
- Anxiety common in elderly
Physical Findings of Thyrotoxic Crisis
- Fever, with consistent rise in temperature by about 38.5°C.
- Temperature often rises over 41°C.
- Excessive sweating
- Condition can gradually progress to hyperpyrexia.
The Cardiovascular signs include:
- Hypertension during initial stages
- Wide pulse pressure
- Hypotension at later stages resulting in shock
- High-output heart failure signs include
- Cardiac arrhythmia
- Supraventricular arrhythmias such as atrial fibrillation and atrial flutter are more common
- Ventricular tachycardia
Neurologic signs include:
- Transient pyramidal signs
Signs of thyrotoxicosis include:
- Orbital signs
Causes of Thyrotoxic Crisis in Cases With Thyrotoxicosis Include:
- Anesthesia induction
- Ingestion of excessive thyroid hormone (TH)
- Radioactive iodine (RAI) therapy
- Medications such as adrenergic and anticholinergic drugs like salicylates, pseudoephedrine, chemotherapy, non-steroidal anti-inflammatory drugs (NSAIDs)
- Abrupt withdrawal of anti-thyroid medications
- Excessive palpation of an enlarged thyroid
- Diabetic ketoacidosis
- Trauma to the thyroid gland
- Toxemia of pregnancy and molar pregnancy
- Children with thyrotoxicosis due to Graves’ disease
- McCune-Albright syndrome
- Crossing of Maternal thyroid-stimulating immunoglobulins through the placental barrier
- Tumor secreting thyroid stimulating hormone (TSH)
- Overactive multi-nodular goiter
- Hyperactive thyroid nodule
- Autoimmune conditions like:
- Juvenile rheumatoid arthritis
- Type I diabetes
- Addison disease
- Chronic lymphocytic (Hashimoto) thyroiditis
- Myasthenia gravis
- Chronic active hepatitis
- Systemic lupus erythematosus
- Nephrotic syndrome
Mechanism of Thyrotoxic crisis
Thyrotoxic crisis is a rare medical emergency that occurs due to an aggravated hyperthyroidism due to the de-compensation of one or more organs in untreated cases. This condition requires early diagnosis and aggressive treatment to prevent serious health complications. Thyroid storm is generally presented by cases with toxic multi-nodular goiter or toxic adenoma, although it commonly affects cases with Graves’ disease.
The condition generally involves dehydration and hyperpyrexia (more than 41°C)
Heart rate over 140 beats per minute that may or may not be accompanied by hypotension, congestive heart failure, atrial dysrhythmias, other arrhythmia, or atrial fibrillation.
- abdominal pain
Thyrotoxic crisis is generally triggered by trauma, intercurrent illness, or emergency surgery.
- acute illness
- Non-compliant anti-thyroid medication
- Recent trauma
- Surgical stress
- Myocardial infarction
- Pulmonary embolism
- Diabetic ketoacidosis
- radiographic contrast media likeradio-iodine
- thyroid hormone tablet overdose
- Recent thyroid surgery
Diagnosis of thyrotoxic crisis
Thyrotoxic crisis can be confirmed with the following diagnostic tests, which help to determine the main cause of the condition
- Infection screen
- Thyroid function tests: elevated T3 uptake, elevated T3 and T4 levels, and reduced TSH levels
- Chest X-ray
- Arterial blood gases and pH
Treatment for thyrotoxic crisis
Treatment protocol is based on the type of triggering agent like any infection. Includes resuscitation of intravenous oxygen, 0.9% saline infusion and nasogastric tube in case of vomiting.
Treatment with Anti-thyroid medications:
- Oral administration o fCarbimazole or propylthiouracil followed by intake of Lugol’s solution (aqueous iodine oral solution) after4 hours.
- Beta blockers like IV propranolol 5 mg, followed by oral administration later, or an alternative, Diltiazem can be taken.
- Administration of intravenous hydrocortisone which inhibits the conversion of T4 to T3
- Sedation with chlorpromazine is recommended in cases with severe agitation.
- Tepid sponging and with paracetamol intake is advised.
Treatment for heart failure:
- High-dose digoxin can be administered.
- Patient should be converted to euthyroid before treating with Cardioversion for atrial fibrillation.
- Furosemide or bumetanide are recommended based on the severity of dehydration and pulmonary edema.
- Anticoagulants: prophylactic subcutaneous heparin is effective in treating thromboembolism; while atrial fibrillation can be treated with intravenous infusion.
- Patient may need haemodialysis or peritoneal dialysis if the condition doesn’t improve.
Prognosis of thyrotoxic crisis
- Untreated thyrotoxic crisis can be life threatening and can prove to be fatal.
- The mortality rate ranges from between 20-50% following, early diagnosis and immediate treatment.
Filed Under: Thyrotoxic Crisis