OVERVIEW
A life-threatening endocrine emergency characterized by high fever, profuse sweating, rapid heartbeat, irritability, and anxiety caused by a combination of thyrotoxicosis and triggers, the most common cause of which is Graves’ disease, which is aggressively treated with antithyroid medications, inorganic iodides, and beta-blockers to remove triggers
Definition
Thyroid crisis is a syndrome of acute exacerbation of thyrotoxicosis that occurs as a result of a large amount of thyroid hormones entering the circulation for a short period of time.
Thyroid crisis may be characterized by generalized metabolic disturbances and abnormalities in the functioning of various systems, and may lead to death without timely and effective treatment.
Incidence
A study in the United States showed that 16.2% of patients diagnosed with thyrotoxicosis from 2004 to 2013 were diagnosed with thyroid crisis, with an overall annual incidence rate of (0.57-0.76)/100,000 people and an annual incidence rate of (4.8-5.6)/100,000 people among hospitalized patients.
Among hospitalized patients in Japan, the annual incidence of thyroid crisis is 0.2/100,000, and the number of patients accounts for 0.22% of all patients with thyrotoxicosis, 5.4% of hospitalized patients with thyrotoxicosis, and the morbidity and mortality rate is more than 10%.
Etiology
The occurrence of thyroid crisis is associated with a rapid increase in the level of thyroid hormones in the circulation, so this section focuses on the causes of increased levels of thyroid hormones and their predisposing factors.
Causes
Autoimmune thyroid diseases, including Graves’ disease and Hashimoto’s thyroiditis combined with hyperthyroidism.
Autonomic thyroid disorders, including autonomous hyperfunctional thyroid adenoma, toxic nodular goiter, etc.
Thyroid-stimulating hormone-mediated disorders, including pituitary thyroid-stimulating hormone adenoma, etc.
Human chorionic gonadotropin-mediated disorders, including severe vomiting of pregnancy, trophoblastic disease, etc.
Thyroiditis, including painless thyroiditis, subacute thyroiditis, acute suppurative thyroiditis, amiodarone-induced thyroiditis, radiological thyroiditis, and extruded thyroiditis
Ectopic hyperthyroidism, including ovarian goiter, metastatic thyroid cancer, etc.
Predisposing factors
Underlying diseases
Including infection; myocardial infarction; pulmonary embolism; diabetic ketoacidosis; hypoglycemia; cerebrovascular accident, etc.
Surgical trauma
Including thyroid surgery; non-thyroid surgery; burns; trauma; violent operations on the thyroid gland, etc.
Drug factors
Including sudden interruption of treatment with antithyroid drugs; radioactive iodine therapy; iodine contrast exposure; use of anesthetics, salicylates, pseudoephedrine, and amiodarone drugs; interferon therapy, etc.
Other factors
Including mental stress; strenuous exercise, etc.
Symptoms
Main Symptoms
Symptoms of hypermetabolic, hyperadrenergic response
High or excessive fever (body temperature over 40°C); profuse sweating.
Significantly increased heart rate (over 140 beats/minute), panic palpitations, shortness of breath.
Flushing of the face and hot flashes on the skin.
Significant body wasting, etc.
Nervous system symptoms
Irritability and anxiety.
Lack of clarity of mind, babbling, or even unconsciousness, etc.
Digestive System Symptoms
Nausea, vomiting, diarrhea.
Jaundice with yellowing of the skin and sclera.
Other symptoms
When apathetic hyperthyroidism presents with thyroid crisis, there will be an apathetic expression, unresponsiveness, lethargy, and even the body presents a kind of wooden stiffness, weakness and powerlessness, while the body temperature is usually only moderately elevated, and there is not much sweating, and the heartbeat is not too fast either.
Consultation
Department of Medicine
Endocrinology
Patients with hyperthyroidism are advised to seek medical attention when they develop fever, rapid heartbeat, nausea, vomiting and diarrhea.
Emergency Department
If there is high fever, profuse sweating, frequent vomiting, agitation, or even coma, it is recommended to consult a doctor immediately.
Preparation for medical treatment
Preparation for medical consultation: registration, preparation of documents, common problems
Tips
Do not put on any make-up before going to the doctor to avoid covering up your condition.
Record temperature changes for the doctor’s reference.
Preparation Checklist
Symptom list
Especially focus on the time of onset of symptoms, special manifestations, etc.
Is there fever? What is the highest temperature? How long has it lasted?
Is there weight loss?
Is there excessive sweating?
Are there any signs of panic or shortness of breath?
Was there nausea, vomiting, diarrhea?
Medical History List
Any history of hyperthyroidism?
Any recent history of surgery or trauma?
Any history of hyperthyroidism in parents, siblings?
Checklist
Test results in the last six months, which can be brought to the doctor’s office
Laboratory tests: thyroid function test, blood routine, blood biochemistry, etc.
Imaging tests: thyroid ultrasound, etc.
Others: Electrocardiogram, etc.
Medication List
Medications used in the last 3 months, if available in boxes or packages, bring with you to the doctor’s office
Antithyroid drugs: propylthiouracil, methimazole, carbimazole.
Beta-blockers: propranolol, metoprolol, bisoprolol, etc.
Diagnosis
Diagnosis is based on
Medical history
The patient has a history of thyrotoxicosis-related illnesses, and there are triggers such as trauma, surgery, infection, and mental stimulation.
Clinical manifestations
Symptoms
There may be high fever, panic palpitations, emaciation, nausea, vomiting, diarrhea, irritability, and anxiety.
Signs
In congestive heart failure, chest auscultation may reveal wet rales (like the sound of bursting water bubbles) at the bottom of both lungs, and edema of the feet and legs.
Laboratory Tests
Thyroid function tests
In general, if thyroid crisis is suspected, thyroid function tests, especially serum free triiodothyronine (FT3), free thyroxine (FT4), and thyrotropin (TSH) levels, should be performed immediately.
A decrease in TSH and an increase in FT3 and FT4 may be seen.
Blood Tests
There may be an increase in leukocytes and an elevated percentage of neutrophils, which may indicate the presence of infection.
Electrolytes
Electrolyte tests are needed to determine whether electrolyte disorders are present.
Thyroid Color Doppler
This test can be used to determine whether hyperthyroidism is due to simple thyrotoxicosis or thyrotoxicosis due to inflammatory destruction of the thyroid gland.
Electrocardiogram
An electrocardiogram usually shows sinus tachycardia and may also show signs of atrial fibrillation.
Treatment
Treatment aims: to control the progression of the disease, relieve symptoms and reduce complications.
Treatment principle: Eliminate the causative factors, reduce thyrotoxicosis as soon as possible, and relieve clinical symptoms.
Elimination of triggers
If there is infection, anti-infection treatment should be carried out actively, and effective antibiotics should be used in time for bacterial infection.
If there are traumas or surgical incisions, do a good job of cleaning and disinfecting the wound to reduce the pain of trauma.
Those caused by mental stimulation need active psychological intervention.
Supportive and symptomatic treatment
Monitor vital signs, monitor the patient’s respiration, blood pressure, temperature, heart rate and other vital signs.
Correct electrolyte and acid-base balance.
Administer oxygen.
Medication
Antithyroid drugs
The drug of choice is propylthiouracil, which reduces the conversion of thyroxine to triiodothyronine.
Also methimazole can be used, which inhibits the organicization of iodine and avoids the coupling of iodine to thyroid tyrosine, which can reduce the synthesis of thyroid hormones.
It is important to note that common adverse effects of antithyroid medications include pruritus, urticaria, arthralgia, and in severe cases, granulocyte deficiency, toxic liver disease, and vasculitis.
Inorganic Iodides
Oral inorganic iodides include Lugol’s Iodine Solution (Lugol’s Iodine Solution) and Saturated Solution of Potassium Iodide (SSKI). Routes of administration for inorganic iodides include oral, sublingual, rectal, or transnasogastric tubes, and the choice needs to be made under medical supervision.
It is important to note that these medications may promote thyroxine synthesis and exacerbate hyperthyroidism instead, so they should be gradually discontinued after the thyroid crisis is controlled [4].
Glucocorticoids
Commonly used, such as hydrocortisone and dexamethasone, can inhibit the synthesis of thyroid hormones and the conversion of peripheral T4 to T3.
It is important to note that this class of drugs should not be used in large quantities for long periods of time, and they need to be tapered until discontinued.
During the application of glucocorticoids, potential adverse effects such as hyperglycemia, peptic ulcer and infection should be closely monitored and prevented.
Beta-blockers
Commonly used including propranolol, etc.
Helps to reduce the response of the tissues around the body to thyroid hormones, thus reducing the symptoms of hyperthyroidism. And it can lower the heart rate.
However, it is important to note that this medication should not be used in patients with heart block, bronchial asthma, etc. You can switch to calcium channel blockers, such as diltiazem and other drugs, to control the heart rate.
Antipyretic drugs
If the temperature remains high after physical cooling, acetaminophen can be given for treatment, and salicylic acid drugs, such as sodium salicylate, are contraindicated.
Dialysis and plasma exchange
If symptoms do not improve within 24 to 48 hours after treatment with antithyroid medications, inorganic iodide, glucocorticoids, or beta-blockers, as well as removal of triggers and treatment of complications, plasmapheresis should be considered for patients with thyroid crisis.
Plasma exchange can rapidly lower the body’s thyroid hormone levels and relieve the symptoms of thyrotoxicosis.
A combination of plasma exchange therapy and continuous hemodialysis filtration is recommended for patients with thyrotoxic crisis who have multiple organ failure.
Prognosis
Cure
Overall prognosis
Untreated
If thyroid crisis is not treated promptly and effectively, patients may develop complications such as hepatocellular damage, gastrointestinal bleeding, and may even die from multiple organ failure.
After treatment
Thyroid crisis is a rather dangerous emergency, but if timely and effective treatment is provided and hyperthyroidism is effectively controlled, the prognosis is generally good.
Prognostic factors
Early diagnosis and treatment
Timely detection and treatment of thyroid crisis can prevent symptoms from worsening and complications from occurring. Failure to seek prompt medical attention and effective treatment can result in death.
Effective control of triggers
If severe mental stimulation, major surgery or severe physical trauma is not effectively controlled after the onset of thyroid crisis, thyroid crisis will be difficult to control and may result in death.
Daily
Daily Management
Dietary management
Avoid iodine-containing foods, including various kinds of seafood such as kelp and nori.
For a balanced diet, consume more fresh vegetables and fruits, and increase the amount of high-quality proteins such as milk, eggs, lean meat (beef, etc.) and soybean products.
Life management
At the time of seasonal change, pay attention to prevent cold and keep warm, avoid cold and respiratory tract infection.
When laboring and working, be cautious and careful to avoid accidents and prevent trauma.
Psychological support
It is important to maintain a cheerful mood and exercise your emotional stress capacity in general to avoid drastic stress reactions in the body due to emotional stimulation.
Others
Patients should actively treat hyperthyroidism to effectively control the function of the thyroid gland. Take medication in strict accordance with the doctor’s instructions and avoid stopping, reducing or changing medication without authorization.
Disease monitoring
Monitor weight changes. If sudden weight loss is detected, consult a doctor promptly.
Monitor body temperature, if you find that the body temperature is suddenly high, you should consult a doctor.
If you are going to have an operation in the near future, or if you are going to be pregnant or give birth, tell your doctor that you have a history of hyperthyroidism so that you can take precautions in advance.
Follow-up review
It is recommended that patients follow the doctor’s instructions for regular follow-up after discharge from the hospital, in order to understand the changes in the condition and to detect the recurrence of thyroid crisis at an early stage.
Prevention
Maintain a reasonable diet.
Maintain emotional stability and avoid suffering from great mental stimulation.
Strictly follow the doctor’s instructions to take the medication for hyperthyroidism, do not reduce or stop the medication without authorization.
Patients with hyperthyroidism need to be careful when choosing radioactive iodine therapy and surgical treatment, closely monitor the level of thyroid hormones and the patient’s general condition, and be vigilant against triggering thyroid crisis.