A 25-year-old woman, gravida 1 para 1, is evaluated for fatigue, palpitation, excessive sweating, and tremor that began 2 weeks ago. Two months before the current visit, she delivered a male child at 39 weeks gestation by an uncomplicated vaginal delivery. The patient has been breastfeeding her infant. She reports no chronic medical conditions. Blood pressure is 140/70 mm Hg and pulse is 110/min. Examination of the thyroid gland shows mild, nontender, diffuse enlargement without an audible bruit. Bilateral lid lag is noted without proptosis or eye redness. A fine tremor of her outstretched hands is present. Deep tendon reflexes are brisk and symmetrical. Laboratory results are as follows: In addition to propranolol, which of the following is the best therapy for this patient at this time?

Question

A 25-year-old woman, gravida 1 para 1, is evaluated for fatigue, palpitation, excessive sweating, and tremor that began 2 weeks ago.  Two months before the current visit, she delivered a male child at 39 weeks gestation by an uncomplicated vaginal delivery.  The patient has been breastfeeding her infant.  She reports no chronic medical conditions.  Blood pressure is 140/70 mm Hg and pulse is 110/min.  Examination of the thyroid gland shows mild, nontender, diffuse enlargement without an audible bruit.  Bilateral lid lag is noted without proptosis or eye redness.  A fine tremor of her outstretched hands is present.  Deep tendon reflexes are brisk and symmetrical.  Laboratory results are as follows:  In addition to propranolol, which of the following is the best therapy for this patient at this time?

Quizplus · Accepted Answer

11ec25c8_d309_bbc6_bc81_d99b435109a9_MD0003_00 This patient has hyperthyroidism, presenting with sweating, tremor, and tachycardia, associated with elevated free thyroid hormone (ie, T4, T3) levels and a suppressed TSH. In light of her recent childbirth, positive thyroid peroxidase antibody assay (marker for autoimmune thyroid disease), and negative thyrotropin receptor antibody assay (marker for Graves disease), this likely represents postpartum thyroiditis. Postpartum thyroiditis is similar to silent (sporadic) thyroiditis but by convention occurs <12 months after parturition. It is characterized by lymphocytic infiltration of the thyroid gland and disruption of thyroid follicles. Therefore, it causes hyperthyroidism due to release of preformed thyroid hormone. Radioiodine uptake (which measures uptake and organification of iodine) is low due to the suppressed metabolic activity of the gland but is not always needed for diagnosis and is frequently deferred in patients who are breastfeeding. silent (sporadic) thyroiditis Hyperthyroidism in postpartum thyroiditis is self-limited and typically resolves within a few months; a beta blocker (eg, propranolol) should be prescribed to attenuate hyperadrenergic symptoms, but specific treatment is not typically necessary. However, many patients subsequently experience a transient hypothyroid phase due to depletion of thyroid hormone and therefore warrant serial laboratory tests (ie, TSH, thyroid hormone levels) until they return to a euthyroid state. transient hypothyroid phase (Choice A) Prednisone or nonsteroidal anti-inflammatory drugs are used for treatment of subacute (de Quervain/granulomatous) thyroiditis, a postviral syndrome characterized by granulomatous inflammation of the thyroid. Like postpartum thyroiditis, subacute thyroiditis can cause hyperthyroidism due to release of preformed hormone. However, patients typically have neck pain and a tender goiter. (Choice B) Thionamides (eg, methimazole, propylthiouracil) inhibit synthesis of thyroid hormone. Hyperthyroidism in postpartum thyroiditis is due to release of preformed hormone, and so these agents are ineffective. (Choices D and E) Unlike the self-limited hyperthyroidism in postpartum thyroiditis, Graves disease causes persistent, progressive hyperthyroidism that often requires definitive management with radioiodine ablation or thyroidectomy. However, this patient has a negative assay for thyrotropin receptor antibodies and no specific examination findings of Graves disease (eg, proptosis, pretibial myxedema); lid lag is a nonspecific sign related to increased sympathetic activity that may be seen in hyperthyroidism of any cause. Educational objective: Postpartum thyroiditis is an autoimmune disorder characterized by lymphocytic inflammation of the thyroid and disruption of thyroid follicles occurring <12 months after parturition. It can cause a self-limited hyperthyroid phase due to release of preformed thyroid hormone. Management includes a beta blocker to attenuate adrenergic symptoms, but specific antithyroid therapy is not usually needed.

A 25-Year-Old Woman, Gravida 1 Para 1, Is Evaluated for Fatigue