Single best answer:
1. A 38-year-old
African-American female presents with dyspnea, fatigue and weight loss.
Laboratory
Studies
Blood urea
nitrogen48 mg/dL
Serum
creatinine4.4 mg/dL
Serum albumin3.9
g/dL
Serum
calcium11.7 mg/dL
Serum
phosphorus5.2 mg/dL
Serum
immunoreactive parathyroid hormone (intact) 2.8 pg/mL (Normal range 10-65 pg/mL)
Serum 25-hydroxy
cholecalciferol 11 pg/mL (Normal range 9-43 pg/mL)
Serum
1,25-dihydroxy cholecalciferol 109 pg/mL
(Normal range 15-60 pg/mL)
24-hour urine
calcium 325 mg
The most likely
cause of hypercalcemia in this patient is:
A. Primary
hyperparathyroidism
B. Familial
hypocalciuric hypercalcemia
C. Sarcoidosis
D. Munchausen’s
syndrome
E. Occult
malignancy
2. A
56-year-old male with end-stage renal disease secondary to polycystic kidney
disease is maintained on hemodialysis. His medications include lisinopril,
erythropoietin, calcitriol, calcium acetate and multivitamin.
Laboratory
Studies
Serum albumin3.5
g/dL
Serum calcium12.1
mg/dL
Serum
phosphorus6.4 mg/dL
Serum
immunoreactive parathyroid hormone
(intact)465 pg/mL (Normal range 10-65 pg/mL)
Which of the
following would NOT be appropriate in the management of this patient:
A. Dietary
phosphate restriction
B. Add paricalcitol
C. Discontinue
calcium acetate and start aluminum hydroxide
D. Discontinue
calcium acetate and start sevalamer
E. Discontinue
calcitriol and start cinacalcet
3. A
17-year-old male presents with severe muscle weakness. He has no past medical
history, denies taking any medications, and his family history is
noncontributory. He is normotensive and physical exam is remarkable only for
mild proximal muscle weakness.
Laboratory
Studies
Serum sodium139
mEq/L
Serum
potassium3.4 mEq/L
Serum chloride108
mEq/L
Serum
bicarbonate28 mEq/L
Blood urea
nitrogen12 mg/dL
Serum
creatinine1.2 mg/dL
Serum calcium9.8
mg/dL
Serum
magnesium1.0 mg/dL
Serum
phosphorus3.2 mg/dL
24-hour urine
140 mg magnesium
24-hour urine
calcium 54 mg
Which of the following
is the most likely cause of his hypomagnesemia:
A. Surreptitious
loop diuretic use
B. Laxative
abuse
C. Surreptitious
vomiting
D. Gitelman
syndrome
E. Conn syndrome
4. All the
following medications can cause hypomagnesemia EXCEPT:
A. Amphotericin
B. Gentamicin
C. Cyclosporine
D. Cisplatin
E. Levofloxacin
5. An
18-year-old woman presents with a 27-lb weight loss over five months. She is
amenorrheic. On examination she is cachectic and has lanugo hair and erosion of
the enamel on her upper incisors. Her height is 64 inches, weight 80 lb, pulse
rate 42 per minute, blood pressure 75/50 mm Hg. Her initial serum electrolytes
are normal. She is admitted to hospital and commenced on a regular diet of 1000
kcal/day, and increased by 200 kcal/day every 2 days. On day 7, she becomes
confused and disorientated with auditory and visual hallucinations.
Which of the
following statements about this patient is likely to be correct:
A. She is at
risk of sudden death
B. Her current
condition is caused by inade quate caloric replacement
C. The corrected
QT interval on her electrocar diogram is shorter than normal
D. Her current
condition may be corrected with insulin
E. Her total
body phosphorus stores are normal
