Question

Based on “Morgan: A case of Diabetes” by Lisa Rubin and Clyde Freeman Herreid (National Center for Case Study Teaching in Science)

The Patient:

Morgan Water is a 27-year old Native American that lives on a reservation in Oklahoma. Nearly ¼ of Morgan’s tribe has diabetes but she has no direct family history of diabetes, heart disease, or other serious conditions. She is however obese (BMI = 32) and leads a sedentary lifestyle. Morgan has been suffering from an increasing persistence of symptoms including unusual thirst, dizziness, blurred vision, and numbness in her right foot. The symptoms have been developing over several months but as she is planning her wedding she attributed them to nerves. She is finally persuaded to see her family doctor. Her non-fasting blood glucose level was elevated so the doctor has her return the next morning for a fasting blood sample so they could more accurately measure her blood glucose and insulin. Her blood results are below:

Test	Morgan’s values	Normal range	Pre-Diabetic range	Diabetic range
Plasma glucose, mg/dl	260	70 -139	140 - 199	≥ 200
Fasting glucose, mg/dl	140	≤ 99	100 - 125	≥ 126
A1C, %	7.6	~ 5	5.7 – 6.4	≥ 6.5
Fasting Insulin, mIU/ml	34	2 - 10	10 - 20	≥ 20

Question 1:

Based on her history and blood results, what do you think is the most likely diagnosis for Morgan?

A. Type I Diabetes Mellitus

B. Type II Diabetes Mellitus

C. Pre-Diabetes

D. Cardiovascular Disease

Question 2:

What is the cause of Morgan’s disease?

A. It is an auto-immune disorder that destroys the β-cells of her pancreas so she produces less

insulin than normal.

B. She has a genetic mutation that results in less insulin receptor being produced than normal.

C. She has developed insulin resistance, where her insulin receptors do not recognize the insulin her

body produces, likely due to her obesity.

D. There is no known cause, it can happen spontaneously.

Morgan is worried that she will have to spend the rest of her life giving herself injections but her doctor does not prescribe insulin injections.

Question 3:

Why would injections of insulin not help Morgan if she has hyperglycemia?

A. Her body is already producing excess insulin but not responding to it.

B. Her problem is with her insulin receptors responding to insulin.

C. Excess insulin will only exacerbate her insulin resistance.

D. All of the above.

Question 4:

Given Morgan’s metabolic state, which of the following pathways would you expect to be active in Morgan’s cells (select all that apply)?

A. Glycolysis

B. Gluconeogenesis

C. β-oxidation

D. Amino acid degradation

E. Protein synthesis