The Case of the Cold and Constipated Car Mechanic
Endocrine System Clinical Case Study
Linda Johnson, a 40 year-old car mechanic, reported to her family physician a three-month
history of gradually progressive constipation. She told her physician that prior to three
months ago, her bowel movements were normal and occurred once every day. Currently
she was having only one bowel a movement every three days. Linda also told her physician
that she felt cold all the time; when her family members were comfortable in a room with
the thermostat set at 70°, she felt cold unless it was turned up to 74°.
Past medical history: negative
Physical Examination:
Weight: 160 pounds (increase of 20 pounds from one year ago).
Height: 5 feet, 2 inches
Temperature: 96.8° Fahrenheit. Respirations: 12. Pulse: 46. Blood Pressure 110/85.
Skin: Dry without any obvious rash.
Head: Thinner than normal and very dry.
Neck: Thyroid gland mildly enlarged and nontender.
Neurologic exam: Deep tendon reflexes such as the ankle jerks showed slight "hang-up" -the relaxation phase seemed prolonged.
QUESTIONS
Answer the questions below to demonstrate your knowledge.
1. What historical questions would you want to know regarding the patient's mood, energy
level, hand pain, and voice? What answers would you anticipate to these questions?
2. What is Linda's probable diagnosis? What historical and physical exam data support this
diagnosis?
3. What do you think the patient's basal metabolic rate is: high, normal, or low? What
historical or physical exam data supports your answer? What is the basal metabolic rate in
most obese individuals?
4. Laboratory Results
The laboratory data revealed the following:
Thyroid Stimulating Hormone (TSH)=8 mU/L (normal=0.4-5 mU/L)
Thyroxine (T4)=50 nmol/L (normal-64-154 nmol/L)
Which of the above laboratory values rule out the pituitary as a cause of Linda's problems?
5. Explain the patient's lab values in terms of a positive or negative feedback mechanism.