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Free STEP3 Exam Braindumps (page: 27)

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A 54-year-old man presents with a 3-cm right thyroid nodule that was found incidentally by the patient while shaving. He denies any pain or discomfort. He denies any history of thyroid disease, any family history of thyroid disease, and any history of head/neck irradiation. He notes a 10-lb weight loss over the past 6 months. His examination is only remarkable for the firm right thyroid nodule. The remainder of the thyroid is not palpable. There is no adenopathy. Heart rate is 90/minute and regular. The skin is warm and moist, and a fine tremor is present when he holds his hands out. TSH level is <.02 U/mL.

Which of the following is the most appropriate next step?

  1. thyroid ultrasound
  2. antithyroid peroxidase antibodies
  3. thyroid-stimulating immunoglobulins
  4. fine needle aspiration of the nodule
  5. thyroid nuclear scan

Answer(s): E

Explanation:

The very low TSH suggests that the patient is hyperthyroid, most likely because of an autonomously functioning thyroid adenoma or hot nodule. In general, these nodules are more than 3 cm in diameter in order to be associated with hyperthyroidism. They are associated with a very low rate of malignancy and do not require fine needle aspiration. The diagnosis would be confirmed by the finding of uptake in the area of the nodule on scan with suppression of uptake in the rest of the thyroid.



A 19-year-old woman who is 2 months postpartum complains of palpitations, heat intolerance, tremulousness, weight loss, and fatigue. Her thyroid is prominent and firm but nontender. Serum TSH level was undetectable. A nuclear medicine radioactive iodine uptake is performed and shows no uptake of iodine in the neck.

Which of the following is the most appropriate next step?

  1. administer radioactive iodine
  2. initiate glucocorticoid therapy
  3. initiate levothyroxine therapy
  4. initiate propranolol therapy
  5. initiate methimazole therapy

Answer(s): D

Explanation:

The patient has the clinical features of hyperthyroidism due to postpartum thyroiditis. This is caused by an autoimmune process with leakage of stored thyroid hormone from the gland. The hyperthyroidism is self- limited and is not associated with new synthesis of thyroid hormone. Therefore, methimazole is not indicated. The thyroid is not painful, as it is in subacute (de Quervain) thyroiditis, so glucocorticoids are not indicated. The radioactive iodine uptake is low, so radioactive iodine treatment is not indicated. Symptom control with propranolol is the only therapy needed during this phase of the illness.



A 60-year-old man with a history of severe chronic obstructive pulmonary disease (COPD), which is steroid dependent, is admitted to the ICU with pulmonary infiltrates and a sepsis syndrome. His hospital course is complicated by acute renal insufficiency and respiratory failure. Therapy includes glucocorticoids and dopamine. He has no history of thyroid disease. Several weeks into his hospital course, the following laboratory studies are performed:

Based on these laboratory studies, which of the following is the most appropriate next step?

  1. initiate levothyroxine therapy
  2. discontinue glucocorticoid therapy
  3. initiate methimazole therapy
  4. order MRI of the pituitary
  5. supportive treatment only

Answer(s): E

Explanation:

The patient exhibits the typical features of the nonthyroidal illness syndrome. The total thyroxine level is low, but TBG is also low (based on the elevated T3 resin uptake), so that the free thyroid index is still in the normal range. The low TBG is related to the patient's nutritional deficiency. The low T3 and TSH levels are related to his illness and the use of both glucocorticoids and dopamine, which decrease TSH. The reverse T3 level is high because of the blockade of T4 to T3 conversion caused by the illness. This finding excludes hypopituitarism as an underlying cause. There is no specific therapy for this problem other than treating the underlying illness.



A28-year-old woman presents for evaluation of primary infertility. She has had fewer than four periods per year since menarche at age 14, facial hirsutism, acne, and weight gain. On examination, she has a BP 150/100. Her body mass index (BMI) is 40. Acanthosis nigricans is noted along the posterior surface of her neck.

Which of the following laboratory studies is most likely to be abnormal in this patient?

  1. TSH
  2. prolactin
  3. glucose tolerance test
  4. growth hormone
  5. cosyntropin (Cortrosyn) stimulation test

Answer(s): C

Explanation:

The patient has the typical features of PCOS associated with insulin resistance and the metabolic syndrome. The presence of hyperandrogenism and oligomenorrhea, without other known causes (such as congenital adrenal hyperplasia), makes the diagnosis of PCOS. The hirsutism and acne are the result of the hyperandrogenism associated with PCOS. Thyroid disorders and hyperprolactinemia can contribute to menstrual disturbances but would not be expected to cause the signs of androgen excess or A. nigricans. A cosyntropin stimulation test would be used for the diagnosis of adrenal insufficiency. Growth hormone levels may be elevated in acromegaly or in some pituitary tumors. Women with PCOS have a high risk of glucose intolerance, diabetes, dyslipidemia, and hypertension. Individuals with insulin resistance syndromes typically exhibit hypertriglyceridemia with low HDLlevels. The key to management of PCOS is weight loss. Even modest weight loss (1020 lbs) can result in significant improvement in metabolic and physiologic parameters, such as blood pressure and insulin resistance, and improved fertility.






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