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Question 8#

A 36-year-old woman presents with delirium and congestive heart failure. Her husband indicates that she has been losing weight and becoming more anxious and irritable over the past 3 months. Over the past several weeks she has developed dyspnea and peripheral edema. She has previously been healthy and takes no medications. Her husband says that she drinks alcohol moderately and has never used illicit drugs. On physical examination, she is awake, anxious, and confused. Her temperature is 38°C and her heart rate is 142 and regular. She has jugular venous distension to 16 cm above the sternal angle as well as bibasilar rales. In addition, she has a diffuse goiter with a soft bruit over each lobe, as well as a stare expression and exophthalmos. CXR shows pulmonary edema and cardiomegaly. Her EKG reveals sinus tachycardia but is otherwise unremarkable. What is the best approach to management of this patient?

A. Admit to the general medicine ward, obtain serum-free T₄ and TSH, order a radioiodine uptake and scan, and begin furosemide 40 mg IV daily
B. Order free T₄ and TSH, start the patient on propranolol 20 mg po tid and lasix 40 mg po bid, obtain a radioiodine uptake and scan, and follow closely as an outpatient
C. Obtain free T₄ , TSH, and thyroid-stimulating immunoglobulin levels, begin methimazole 10 mg po tid, and follow closely as an outpatient
D. Admit to the general medicine ward, obtain blood and urine cultures and an echocardiogram, and begin treatment with broad-spectrum antibiotics and furosemide
E. Admit the patient to the intensive care unit, order free T₄ and TSH, and begin high-dose propranolol, propylthiouracil, potassium iodide, corticosteroids, furosemide, and acetaminophen

Correct Answer is E

Comment:

This patient has thyroid storm, a medical emergency. The presence of fever, severe tachycardia, congestive heart failure, and CNS changes (delirium, psychosis, seizure, or coma) help separate thyroid storm from uncomplicated hyperthyroidism. Other factors that point toward storm or impending storm include atrial fibrillation, abdominal symptoms, jaundice, and the absence of a precipitating event. Even with treatment, the mortality of thyroid storm can be 10% to 20%, so admission to an intensive care unit for close monitoring is mandatory. Propranolol, generally contraindicated in decompensated congestive heart failure, improves the high-output CHF and, in high doses, helps block conversion of T₄ to the active hormone T₃ . Propylthiouracil blocks the uptake and organification of iodide by the thyroid gland, and oral iodides prevent the release of preformed T₄ and T₃ from the thyroid gland. Relative adrenal insufficiency is often present, so corticosteroids are administered routinely in thyroid storm. Patients with mild to moderate hyperthyroidism are usually evaluated and treated as an outpatient. Impending or threatened thyroid storm can be managed on the general medicine ward or in the ICU as clinically indicated, but overt thyroid storm (as in this patient) requires ICU care. If an outpatient has a diffuse goiter and if the cause of hyperthyroidism is unclear, radioiodine uptake can be measured to distinguish Graves disease (normal or increased RAI uptake) from painless thyroiditis (low RAI uptake). In thyroid storm, however, immediate treatment takes precedence over measuring the 24-hour radioiodide uptake. Furthermore, thyroiditis rarely, if ever, causes thyroid storm. Thyroid-stimulating immunoglobulin assays are rarely needed to diagnose Graves disease. Methimazole is often used in mild to moderate hyperthyroidism because of ease of dosing, but propylthiouracil blocks T₄ to T₃ conversion and should be used in thyroid storm. Although the febrile, tachycardic patient with hyperthyroidism can appear septic, other features of this case strongly suggest that thyroid storm, not infection, is the cause of her illness. Antibiotics without proper management of her hyperthyroidism would probably prove fatal.