In our #AMreport @WCHospital, we discussed a case of clinical hyperthyroidism suspicious for post-viral thyroiditis. A patient presented with a 1 week history of  neck tenderness along with tremors, palpitations, anxiety and diaphoresis that was preceded by an upper respiratory tract illness 2 weeks prior. Her clinical exam was consistent with a state of hyperthryoidism (tremors, tachycardia (HR 120), ⇑ deep tendon reflexes) and  neck tenderness with a slightly enlarged thyroid gland. No thyroid bruits, negative Pemberton’s test.  Symptomatic treatment with β-blockade therapy and NSAIDs while arrangements were made for the radioactive uptake and scan were done in the interim.

What is thyroiditis? 

Thyroidits is an inflammation of thyroid glandular cells that can lead to gland dysfunction. There are many causes of thyroiditis included but not limited to

• Hashimoto’s thyroiditis (chronic lymphocytic thyroiditis).
• Drug-induced thyroiditis
• Post-partum thyroiditis
• Acute and subacute thyroiditis
• Radiation-induced thyroidits
• Silent thyroiditis

The treatment centres around symptomatic relief for patients with beta-blocker therapy for those who have are initially hyperthyroid due to transiently elevated thyroxine levels from glandular destruction (Figure 1). Along with analgesic and anti-inflammatory management with NSAIDs.  Additionally other tests such as anti-TPO antibodies can be used for prognostication purposes in patients who may be at risk for developing hypothyroidism as well as for determining disease activity. About 75% of patients with Graves’ Disease will have a positive anti-TPO test.

Graves’ Disease

• The most common cause of hyperthyroidism in adults [1].
• An autoimmune process due to thyroid stimulating immunoglobulins (TSI) antibodies stimulating the thryoid gland in a similar manner that TSH does but causing an increase in the production of thyroid hormones and gland hyperplasia.
• Graves disease can be treated with antithyroid drugs, radioactive iodine (RAI), or surgery (near-total thyroidectomy) [1].
• A 12- 18 month course of antithyroid drugs can result in remission in about 50% of patients
  • Patients must be counseled on adverse reactions, including agranulocytosis and hepatotoxicity with antithyroid medications. 
• Patients with orbitopathy should be counselled on the importance of
  • smoking cessation
  • pros and cons of surgery
  • risks of worsening orbitopathy with RAI therapy, although risk  can be mitigated with concomitant glucocorticoid therapy in consultation with ophthalmology, endocrinologists and surgeons.

Back to the case:

As demonstrated in figure 2, the diagnosis of Graves’ disease was made after the scan and the patient was placed on antithyroid medications and counseled on smoking cessation.

 Take Home points:

1. In patients with clinical hyperthyroidism investigations should entail a RAI uptake and scan once pregnancy has been ruled out along with no breastfeeding.
2. A viral illness can be a trigger for both subacute thyroiditis and Graves’ disease.
3. The management for thyroiditis centers around symptomatic management  with β-blockade therapy and NSAIDs along with consideration for prednisone as an alternative.
4. The management for Graves’ disease centres around symptomatic management and reducing thyroxine burden with antithyroid medications, surgical resection or radioactive iodine administration.
5. Patients with orbitopathy should be counseled on the importance of smoking cessation.

References:

1. Management of Graves Disease: http://jama.jamanetwork.com/article.aspx?articleid=2475467

–B