Thyroid Hormone Toxicity Workup
- Author: Lisandro Irizarry, MD, MPH, FAAEM; Chief Editor: Asim Tarabar, MD more...
Laboratory Studies
- Most asymptomatic patients do not require diagnostic testing, especially very early after exposure.
- The following tests are indicated in symptomatic patients:
- Complete blood count
- Electrolytes (eg, calcium, magnesium, phosphorous)
- Urinalysis
- Serum acetaminophen level (in patients with intentional exposures and suicidal ideations)
- Arterial blood gas (ABG)
- T3, T4, and T3 resin uptake (RU) levels may be sent 2-6 hours postingestion; however, remember the following:
- These levels offer no aid in the acute phase of clinical management.
- These levels are of no value in determining prognosis.
Other Tests
- ECG is indicated to evaluate symptomatic patients for myocardial ischemia, myocardial infarction, and cardiac dysrhythmias (eg, atrial fibrillation, SVT).
Procedures
- Lumbar puncture (LP) should be considered in patients with hyperthermia and change of mental status to rule out CNS infection.
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