Question

A 25-year-old woman with type 1 diabetes comes to the emergency department complaining of thirst, frequent urination, and weakness. She feels “lightheaded” when she stands. Because of nausea and vomiting after a meal in a restaurant the previous day, she stopped eating and taking her insulin. On examination, she is dehydrated and hypotensive. Her breathing is rapid and deep. 1. Which of the following is likely to be lower than normal? a. Urinary urea levels b. Plasma levels of glucagon c. Plasma levels of free fatty acids d. Blood partial pressure of carbon dioxide e. Plasma acetoacetate levels 2. Which of the following will increase after insulin administration? a. Plasma triglyceride levels b. Plasma K+ levels c. Lipoprotein lipase activity d. Adipose tissue lipase activity e. Plasma phosphate levels For each question, please first clearly indicate which option (a, b, c, d or e) is correct and which one is wrong and then explain briefly your reasoning for each answer. For instance, you must write: "a" is a correct answer because .... "b" is a wrong answer because..... "c" is wrong because ..... :d" is wrong because ...... etc.b

Answer 1

1) answer is c) plasma levels of glucagon.

Glucagon is a hormone released by alpha cells of endocrine pancreas in response to low blood sugar. In this case, women is diabetic which is caused by beta cell destruction or inability to use insulin due to receptor modulation, as glucose uptake is reduced due to insulin activity, more than enough sugar is present which has inhibitory effect on production of glucagon and it's levels decrease.

Option A is incorrect as urea levels will be increased due to decrease in renal perfusion and dehydration in case of diabetes type 1.

Option c is incorrect as plasma fatty free acids will be increased, as there is increased insulin and insulin is antilipolytic hormone but in diabetes insulin dysfunction occurs and in diabetic ketoacidosis fats are broken down to utilise energy which produces ketone bodies.

Option d is incorrect as levels of carbon dioxide will increase due to hypoventilation.

Option e is incorrect as fats are broken down due to which ketone bodies are increased. Acetate is one among them.

2) option c and d is correct.

Adipose tissue lipase breaks down fatty acids increases their metabolisms, after insulin infusion, lipase activity increases which results into reduced levels of fatty acids and molecules after metabolism is carried by lipoproteins.

Option a is incorrect as insulin administration causes decreased levels of triglycerides due to their increased metabolism and decreased synthesis.

Option b is incorrect as potassium levels are decreased after insulin administration as insulin results into increased intracellular transport of potassium along with glucose transport thus reducing potassium levels, excess infusion can cause hypokalemia.

Option e is incorrect as the increased anabolic activity results into formation of phosphate bonds, which causes depletion of phosphate levels and thus their levels is reduced.