Wednesday, March 4, 2015

Study group discussion: Diabetes

I've noticed one thing with my "swedish" medical book.... It always give glucose values in ( mmmol/l ) and not ( mg/dl )

fP-Glucose > 7,0 mmol/l
How much mg/dl is that ?

The conversion factor is   mg/dl= 18 x mmol/l
So 7mmol/l is 126mg/dl
I'm actually majoring in pharmacology :) we had a lot of those ^^

HbA1c < 52 mmol/l = 6 %
For diabetes type 1
Hemoglobin A1c level should be held at 6%
And it's written here HbA1c level should be held < 52 mmol/mol
equals to 6%

*a conversion table was posted on the group by someone which sorted this dilemma*

That might be possible but for the diagnosis it is >6.5

You don't use A1c for diagnosis. It is used only for evaluating control over the last few months!

But now if it's >6.5 he is diagnosed diabetic.

Umm but.. Why would you use such a test when there are better screening tests?

Ummm its part of one of the criteria for diagnosis!! Though getting fasting samples and all are easy but you have to make the patient fast right!! In this one benefit would be take the samples anytime!

Oh yep.. Makes sense!

A diabetic patient is undergoing contrast angiography for some reason. He was asked to stop his oral hypoglycemic, metformin before the procedure. Why?

Lactic acidosis.
Renal failure will worsen it.

Correct! You are concerned about lactic acidosis. Even slight renal failure due to the dye will precipitate lactic acidosis!

A diabetic patient controlled on Insulin develops fainting episodes. On investigations, he was found to have an elevated creatinine. What is the mechanism for the hypoglycemia?

Insulin excreted renally?

Yes, the half life of insulin is increased in renal failure!

A nurse presents with hypoglycemia. Her insulin levels are up but C peptide levels are low. Diagnosis?

Taking exogenous insulin.

Alright. You confront the patient and goes into counselling.

Now the same patient comes with hypoglycemia but this time her insulin and C peptide levels, both are elevated!
What happened this time?

Using sulphonylureas
Oral diabetic drugs - Glipizide, glimipiride, glyburide

Correct! How will you prove it?

proInsulin levels? Just guessing don't know that!!

U/A

What's u/a?

U/A is shortening for urine analysis

Correct! Urine for Sulfonylureas

If the urine test came negative, what could it be?

Insulinoma

And he scores again!

Wonderful questions!!

That'll be all for today!

Thank you for the great questions IkaN.

Never thought questions would be this much fun!

*After which someone else asked us a few review questions based on what he had studied! *

Chlorpropamide

Ok one more!! How would you access severity of diabetic ketoacidosis?

*since no one could guess, we were given hints!*

Let me put in this way.. Which electrolyte would you Check in serum to access severity of DKA?

If you had to check just 1.

Bicarbonate.

Yes!!!

Why bicarbonate?

Because it is acidosis

Yes, you are right!!

Low bicarbonate would lead to what? This one entity is very important in DKA management!  If this is corrected patient is well and good!! Some difference in the cations and anions!! What's that called?

Anion gap

Yes, it is!! Finally!!

This anion gap is very important.

What the normal value?

10 to 15

Does this gap increase or decrease?

Increases.

ABG would tell is about acid base imbalance.

How does neuropathy occur in diabetes? What's the mechanism?

Occlusion of small venules?

Damage to autonomic NS..?

Microvascular occlusion?

Yes, nerves themselves have a supply of blood vessels. Diabetes damages these small blood vessels, thus decreases supply to nerves!!

You all were correct!!

I've read somewhere that sorbitol deposits also damage nerves?

Lens! It causes cataract.

Alright guys!! That's it!! I can't remember any more!!

Any mnemonics?

Here are all the study links!

http://medicowesome.blogspot.ae/2015/01/oral-hypoglycemic-drugs-and-weight.html

http://medicowesome.blogspot.com/2015/02/study-group-discussion-pharmacological_15.html

http://medicowesome.blogspot.ae/2015/02/study-group-discussion-metformin-and.html

http://medicowesome.blogspot.ae/2015/02/study-group-discussion-cardiac.html

http://medicowesome.blogspot.ae/2015/02/study-group-discussion-type-3-diabetes.html