Here’s another USMLE® Step 2 CK Question of the Day! Today’s case involves a 45-year-old woman with altered mental status, nausea, vomiting, and diarrhea. Medical history is remarkable for long-standing Graves disease and gastroesophageal reflux disease. IV propranolol is initiated. Which additional medications should also be administered to this patient?
A 45-year-old woman presents to the emergency department due to agitation and altered mentation. The patient was in her usual state until a few hours ago when she started having severe nausea, vomiting, and diarrhea. Medical history is remarkable for long-standing Graves disease and gastroesophageal reflux disease. Last week, the patient had an upper respiratory infection that resolved without treatment. The patient has been partially compliant in taking her medications, which include omeprazole and propylthiouracil. Temperature is 40°C (104.0°F), pulse is 150/min and irregular, and blood pressure is 150/100 mmHg. On physical examination, the patient is stuporous and her skin is moist. Laboratory tests show elevated liver enzymes, mild hyperglycemia, and leukocytosis. IV propranolol is initiated.
Which of the following additional medications should also be administered to this patient?
A. Hydrocortisone
B. Heparin
C. Ceftriaxone
D. Aspirin
E. Dantrolene
Scroll down for the correct answer!
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The correct answer to today’s USMLE® Step 2 CK Question is…
A. Hydrocortisone
Before we get to the Main Explanation, let’s see why the answer wasn’t B, C, D, or E. Skip to the bottom if you want to see the correct answer right away!
Incorrect answer explanations
Today’s incorrect answers are…
B. Heparin
Incorrect: Heparin is an anticoagulant used in conditions such as venous thromboembolism, deep vein thrombosis, pulmonary embolism, myocardial infarction, stroke, or transient ischemic attack. Although some of this patient’s symptoms could be explained by myocardial infarction, the presence of very high fever, diarrhea, and a long history of Graves disease favors another diagnosis.
C. Ceftriaxone
Incorrect: Ceftriaxone is used to treat bacterial infections caused by gram-negative or gram-positive bacteria. This patient had a viral upper respiratory infection which has since resolved, and her current presentation favors another diagnosis.
D. Aspirin
Incorrect: Aspirin should be given to patients with suspected myocardial infarction. However, this patient’s presentation is more consistent with a thyroid storm. Although antipyretic medications can bring down the patient’s fever, aspirin can increase serum free T4 and T3 concentrations by interfering with their protein binding, and therefore, acetaminophen should be used instead for fever reduction.
E. Dantrolene
Incorrect: Dantrolene is a ryanodine receptor antagonist used in patients with malignant hyperthermia, a life-threatening condition caused after administration of inhaled anesthetics or succinylcholine. The condition causes hyperthermia and severe muscle contractions. This patient did not receive any of the aforementioned medications.medications.
Main Explanation
This patient is presenting with acute onset of nausea, vomiting, diarrhea, arrhythmia, and very high fever. In the light of the known noncompliance with medications and long-standing Graves disease, the most likely diagnosis is a thyroid storm.
Thyroid storm is a rare, life–threatening condition typified by severe clinical manifestations of thyrotoxicosis. The condition is caused by longstanding untreated/undertreated hyperthyroidism (e.g., Graves disease, toxic multinodular goiter, toxic adenoma). It may be precipitated by an acute stress event such as surgery, trauma, infection, iodine overload, or labor. Patients may present with agitation, anxiety, delirium, psychosis, stupor, coma, tachycardia, and congestive heart failure. Hypotension, cardiac arrhythmia, and death from cardiovascular collapse may also occur.
Laboratory findings include overt primary hyperthyroidism: low TSH and high free T4 and/or T3 concentrations. Testing may also reveal mild hyperglycemia, mild hypercalcemia, abnormal liver function tests, leukocytosis, or leukopenia. Treatment includes beta-blockers, antithyroid drugs, iodine solution, and glucocorticoids, as described in the table below.below.
Major Takeaway
Thyroid storm is a life–threatening condition characterized by overt thyrotoxicosis in the setting of longstanding untreated/undertreated hyperthyroidism. It can be precipitated by an acute stress event such as trauma or infection. Patients usually present with altered mental status and cardiovascular instability. Treatment includes beta-blockers, antithyroid drugs, iodine solution, and glucocorticoids.
References
Nayak B, Burman K. Thyrotoxicosis and thyroid storm. Endocrinol Metab Clin North Am 2006; 35:663.
Chiha M, Samarasinghe S, Kabaker AS. Thyroid storm: an updated review. J Intensive Care Med 2015; 30:131.
Ross DS, Burch HB, Cooper DS, et al. 2016 American Thyroid Association Guidelines for Diagnosis and Management of Hyperthyroidism and Other Causes of Thyrotoxicosis. Thyroid 2016; 26:1343.
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