A 28-year-old woman has had difficulty concentrating at work for the past month. She is constantly getting up and walking around to visit co-workers. She complains that the work area is too hot. She seems nervous and often spills her coffee. She has been eating more but has lost 5 kg in the past 2 months. On physical examination her temperature is 37.5°C, pulse 101/minute, respiratory rate 22/minute, and blood pressure 145/85 mm Hg.

Which of the following laboratory findings is most likely to be present in this woman?

A 29-year-old primigravida who received no prenatal care has marked vaginal bleeding after the onset of labor at 38 weeks gestation. Cesarean section is performed and a lacerated low-lying placenta is removed. She remains hypotensive for 6 hours and requires transfusion of 12 packed RBC units. Postpartum, she becomes unable to breast-feed the infant. She does not have a resumption of normal menstrual cycles. She becomes more sluggish and tired. Laboratory findings include hyponatremia, hyperkalemia, and hypoglycemia.

Which of the following pathologic lesions is she most likely to have had following delivery?

A 49-year-old woman has had increasing cold intolerance, weight gain of 4 kg, and sluggishness over the past two years. A physical examination reveals dry, coarse skin and alopecia of the scalp. Her thyroid is not palpably enlarged. Her serum TSH is 11.7 mU/L with thyroxine of 2.1 micrograms/dL. A year ago, anti-thyroglobulin and anti-microsomal autoantibodies were detected at high titer.

Which of the following thyroid diseases is she most likely to have?

A 48-year-old woman has experienced constant back pain exacerbated by movement over the past month. She reports increasing weakness over the past 3 months. On physical examination her blood pressure is 165/110 mm Hg. She is overweight, with a BMI of 28. A radiograph of the spine reveals a compressed fracture at T10. Laboratory findings include a serum glucose of 155 mg/dL.

Which of the following pathologic lesions is most likely to explain her findings?

An 35-year-old woman has had insomnia for the past 4 months, as well as episodes of diarrhea with up to 4 loose stools per day. On physical examination, she exhibits bilateral proptosis. Her outstretched hands have a fine tremor. On palpation of her neck, the thyroid gland does not appear to be enlarged and no masses are palpable. Laboratory studies show a serum TSH of 8.8 microU/mL in association with a serum total thyroxine of 15.1 microgram/dL.

Which of the following is the most likely diagnosis?

A 50-year-old man has episodic headaches for 3 months. On physical examination his blood pressure is 185/110 mm Hg, with no other remarkable findings. Laboratory studies show sodium 145 mmol/L, potassium 4.3 mmol/L, chloride 103 mmol/L, C02 26 mmol/L, glucose 91 mg/dL, and creatinine 1.3 mg/dL. An abdominal CT scan shows a 7 cm left adrenal mass. During surgery, as the left adrenal gland is removed, there a marked rise in blood pressure.

Which of the following laboratory test findings most likely explains his findings?

A 56-year-old woman has had diffuse, dull, constant abdominal pain for the past 2 months. On physical examination no abnormal findings are noted. An abdominal CT scan shows a 3 cm right adrenal mass. The right adrenal is excised and on microscopic examination the mass is composed of cells resembling adrenal cortex.

Which of the following features is the most reliable indicator that this mass is malignant?

A 33-year-old previously healthy man has lateral visual field deficits, but his residual vision is 20/20. His facial features have changed over the past year. His shoe size has increased. A head CT scan reveals enlargement of the sella turcica.

Which of the following hormones is most likely being secreted in excessive amounts in this man?

A 38-year-old woman has had a feeling of fullness in her neck for the past year. She is otherwise asymptomatic. Her physician's assistant palpates a symmetrically enlarged but nontender thyroid gland. She has no difficulty swallowing. There is no palpable lymphadenopathy. She is afebrile. Her serum TSH is 3.5 mU/L with total thyroxine of 8.2 micrograms/dL. Thyroid peroxidase antibody is not detected. Two years later, her thyroid has not appreciably changed in size.

Which of the following conditions is she most likely to have?