Book recommended: Medical Physiology by Jaypee

1. Clinical Scenario-
Parathyroid Gland
DANISH HASSAN
LECTURER, UNIVERSITY OF SARGODHA

2. Case # 01
 A 43-year-old male is admitted to the emergency
room for severe pain in his left flank, radiating to
the groin. The pain is intermittent and initiated
after running a marathon on a hot summer day.
The patient is asked for a urine specimen and
blood is detected in the urine. He is hydrated and
additional diagnostic procedures are done.
Laboratory values show an increased plasma
calcium of 12 mg/dL, and increased plasma
intact PTH values of 130 pg/mL.

3.  Q: Which of the following findings would be
predictable in this patient?
A. increased plasma phosphate
B. increased serum alkaline phosphatase
C. increased intestinal calcium loss
D. decreased urinary calcium excretion

4.  Q: In the patient described above, the
mechanism underlying the abnormalities
observed is
A. increased calcitonin release
B. decreased hepatic 25-hydroxylase activity
C. increased osteoclast apoptosis
D. increased bone resorption

5. Case # 02
 A 73-year-old woman is admitted to the hospital
following a bout of severe vomiting and
generalized weakness. Initial laboratory values
reveal increased plasma calcium levels. The
referring physician tells you that she has breast
cancer and her bone scan indicates metastasis to
bone.

6.  Q: Which of the following blood laboratory values
would be compatible with this clinical scenario?
A. low PTH and phosphate, and high alkaline
phosphatase
B. high PTH and phosphate, and low alkaline
phosphatase
C. low PTH and phosphate, and low alkaline
phosphatase
D. low PTH and phosphate, and normal alkaline
phosphatase

7.  Q: The most likely cause of hypercalcemia in the
patient described in Question is
A. increased PTH production
B. increased responsiveness of the PTH receptor 1
C. increased PTHrP production
D. increased calcitonin release

8.  Q: Hyperventilation usually leads to muscle
cramping (tetanic contractions). What is the
physiologic concept that explains what happens in
that situation?
A. hypercalcemia secondary to PTH-mediated bone
resorption
B. increased dissociation of protein-bound calcium
C. decreased ionized plasma calcium levels
D. increased renal calcium excretion

9. Case # 03
 A postmenopausal patient is referred for
asymptomatic hypercalcemia and history of
repeated episodes of urolithiasis (kidney stones).
Blood laboratory values reveal increases in intact
PTH, 1,25(OH)2D, and markers of bone resorption.
Neck ultrasound revealed a mass below the right
lobe of the thyroid gland.

10.  Q: What is your most probable diagnosis?
 Q: What is the pathophysiology underling
increases in intact PTH, 1,25(OH)2D, and markers
of bone resorption in the blood of this patient?
 Q: What is the patho-physiology underling the
development of kidney stones in this patient?

11. Case # 04
 A 35-year-old woman undergoes a thyroidectomy
for papillary serous thyroid cancer. The surgeon
suspects that the parathyroid glands have been
removed. Which of the following findings is most
likely to be seen in the patient 1 week
postoperatively?
 A. Coma
 B. Constipation
 C. Esophagitis
 D. Muscle spasms and tetany