A 22-year-old female presents with complaints of heat intolerance, sweating and palpitations. She also reports menstrual irregularities, increased appetite and diarrhea. Her pulse is 102/min and regular, blood pressure is 116/80 mm Hg, temperature is 37.2° C (99° F), and respirations are 14/min. Physical examination reveals a diffusely enlarged, nontender thyroid gland. TSH level is 0.05 mU/L. Free T4 and T3 levels are elevated. Radioactive iodine uptake at 24 hours is 50 percent. Thyroid stimulating immunoglobulins are present. She is started on propylthiouracil 300 mg daily in three divided doses. After two weeks, she returns and complains of a sore throat. Her pulse is 98/min and regular, temperature is 38.6° C (101.5° F), blood pressure is 115/76 mm Hg, and respirations are 15/min. The soft palate, pharynx, and tonsils are red and swollen. What is the most appropriate next step in the management of this patient?

Question

A 22-year-old female presents with complaints of heat intolerance, sweating and palpitations.  She also reports menstrual irregularities, increased appetite and diarrhea.  Her pulse is 102/min and regular, blood pressure is 116/80 mm Hg, temperature is 37.2° C (99° F), and respirations are 14/min.  Physical examination reveals a diffusely enlarged, nontender thyroid gland.  TSH level is 0.05 mU/L.  Free T4 and T3 levels are elevated.  Radioactive iodine uptake at 24 hours is 50 percent.  Thyroid stimulating immunoglobulins are present.  She is started on propylthiouracil 300 mg daily in three divided doses.  After two weeks, she returns and complains of a sore throat.  Her pulse is 98/min and regular, temperature is 38.6° C (101.5° F), blood pressure is 115/76 mm Hg, and respirations are 15/min.  The soft palate, pharynx, and tonsils are red and swollen.  What is the most appropriate next step in the management of this patient?

Quizplus · Accepted Answer

The antithyroid drugs propylthiouracil (PTU) and methimazole (MMI) are associated with a number of minor, as well as potentially life-threatening, side effects. Agranulocytosis is the most feared side effect, and is seen in approximately 0.3% of patients treated with antithyroid drugs. It is caused by immune destruction of granulocytes, and most cases occur within 90 days of treatment. Routine monitoring of the granulocyte count is not cost effective and not advocated. Current recommendations state that once the patient complains of fever and sore throat, the antithyroid drug should be discontinued promptly and the WBC count measured. A total WBC count less than 1,000/cubic mm warrants permanent discontinuation of the drug. If the total WBC count is more than 1,500 per cubic mm, antithyroid drug toxicity is unlikely to be the cause of the sore throat and fever. (Choice A) Propranolol can be used for symptomatic relief of thyrotoxic symptoms; however, the most important next step is to discontinue PTU and check the WBC count. (Choice B) Increasing the propylthiouracil dosage would be lethal in this case. (Choice D, E and F) The treatment of antithyroid drug-induced agranulocytosis includes discontinuation of the offending drug and intravenous administration of broad spectrum antibiotics (especially for Pseudomonas). Granulocyte colony stimulating factors may be useful in increasing the WBC count. Throat culture, oral penicillin and acetaminophen can be done/given as part of the evaluation/management (along with CBC with differential count) of this patient; however, these steps are not going to reverse this patient's underlying problem, and are therefore not the appropriate next steps. next Educational Objective: Fever and sore throat in any patient taking antithyroid drugs suggests agranulocytosis. Antithyroid drugs should be stopped and WBC count checked. Routine WBC count measurement in patients taking antithyroid drugs is not cost effective.

A 22-Year-Old Female Presents with Complaints of Heat Intolerance, Sweating