Question

Case Study – Diabetes Mellitus Mohinder, a 28 year old male, had been diagnosed with diabetes mellitus when he was 12 years old. He started experiencing polydipsia, polyuria and polyphagia and his parents noticed that he was very lethargic and seemed continuously fatigued. They would occasionally detect the sweet, “fruity” smell of acetone on his breath. Their PA informed them that this was a sign of ketoacidosis associated with the diabetes. At the time, high fasting glucose levels and islet cell antibodies (ICA) had been detected in his blood. His doctors had him carry out a regimen to control his fluctuations in blood glucose which included diet, exercise and administration of exogenous insulin. At first he was administering insulin 1-3 times a day as indicated by measuring the glucose concentrations in small blood samples obtained from pricking his finger. When he was 22, he got a small battery-powered infusion pump that continuously infused insulin subcutaneously. Now he is considering an experimental treatment that involves implantation of beta-cells derived from donated pancreases. These cells implant in the liver and produce insulin in response to blood glucose levels.

1. Is Mohinder suffering from Type I or Type II diabetes mellitus? How can you tell?

2. What are polydipsia, polyuria and polyphagia? Why are these symptoms of diabetes?

3. What is ketoacidosis? Why is it a consequence of diabetes mellitus?

3. What do the ICA suggest about the etiology of his condition?

4. Why is an insulin infusion pump superior to periodic insulin injections? Why would donated beta-cells be superior to the infusion pump if they can be successfully implanted? (Think about the negative feedback loops for control of blood glucose as you answer this question. How do the concepts of sensitivity, gain and lag time relate to this question?)

5. What are the drawbacks to donated pancreas cells? How might embryonic stem cells be used to avoid these problems?

Answer 1

Question no 1)

Mohinder is suffering from type I diabetes because

• His blood is having antibody against the islets of pancreatic that tells that he is having a autoimmune disorders that destructs the pancreas
• He is on insulin that is no tablets can control type 1 diabetes
• He was having symptoms at childhood so it is type 1

Question no 2)

Polyphagia is the hunger to take more food and this occurs in diabetes as the serum glucose level is high but the cells are not getting enough glucose for metabolism due to lack of insulin

Polyuria is the excess excretion of urine and thus occur because of osmotic diuresis as when glucose is excess the glucose is excreted through the urine so water is also excreted more

Polydypsia is the excess thirst and this occurs as a result of excess output of urine

Question no 3)

Ketoacidosis is the production of ketones that is keto avoids in body as a byproduct of fat metabolism.

In diabetes the glucose amount in blood is high but it cannot be taken into muscle without the help of insulin so to provide energy to muscles our body break down the fat molecules and produce Energy. The byproduct of this reaction is ketones . This results in ketoacidosis.

Question no 4)

ICA suggest that since he is having antibody agains ICA. It might be auto immune disorders that affect the cells of pancreas and this might have brought about destruction of pancreatic cells and tissues leading to type 1 diabetes