Pathophysiology of Type 1 Diabetes

Question 1

The pancreas is a _________-peritoneal organ.

Answer 1

retro (it’s behind the stomach)

Question 2

What fasting labs and oral glucose tolerance tests are diagnostic of diabetes?

Answer 2

Fasting:

• normal: less than 100
• pre-diabetes: 100 - 125
• diabetes: greater than 125

Oral glucose tolerance test:

• normal: less than 140
• pre-diabetes: 140 - 199
• diabetes: greater than 199

Question 3

An HbA1c greater than or equal to _____ is diagnostic of diabetes.

Answer 3

6.5

Question 4

The incidence of type 1 diabetes in the general population is ______, while with a first-degree relative it is _______.

Answer 4

1:300; 1:20

Question 5

The monozygotic twin concordance rate is _______.

Answer 5

between 1:3 and 1:1

Question 6

What three autoimmune disorders are most common in those with type 1 diabetes?

Answer 6

Thyroid disorders, celiac, and Addison’s

Question 7

There are two alleles that are most likely to correlate with or predict type 1 diabetes: ____________. There are many other alleles –most often immune-related –that correlate with diabetes risk.

Answer 7

HLA; insulin production and metabolism

Question 8

What are the four major islet autoantigens that predict diabetes?

Answer 8

• ZnT8
• Islet antigen 2 (IA-2)
• GAA
• Mixed insulin autoantibody (mIAA)

Just note that it’s a little odd that antibodies predict development of T1DM since it is predominantly a T-cell mediated process.

Question 9

What pattern of autoimmune destruction in the pancreas is typical in those with TIDM?

Answer 9

Patchy –like vitiligo

Question 10

What is the accelerator hypothesis?

Answer 10

Based on the observation that the rise in TIDM parallels the rise in obesity, the accelerator hypothesis posits that obesity stresses beta cells and increases likelihood of TIDM.

Question 11

What is LADA?

Answer 11

Latent Autoimmune Diabetes of adulthood… a form of autoimmune diabetes presenting between ages 30 and 70 that has autoantibodies and six months of non-insulin requiring diabetes.

Question 12

True or false: TIIDM is strongly associated with certain HLA isotypes.

Answer 12

False. There is no strong evidence of HLA involvement in TIIDM.

Question 13

Family history is much higher in type ____ diabetes.

Answer 13

2

Question 14

A current trial indicates that giving ______________ can potentially delay TIDM by 10 years.

Answer 14

oral insulin

Question 15

Abatacept blocks ____________.

Answer 15

the CD80/86 receptor needed to activate the T-cell CD28 receptor

Question 16

People typically present with signs and symptoms of diabetes when ________ percent of the beta cells have been destroyed.

Answer 16

80 to 90

Question 17

What HLA is most associated with developing T1DM?

Answer 17

HLA DQB1 0302

Question 18

Decreased duration of ____________ has been shown to increase risk of T1DM.

Answer 18

breastfeeding

Question 19

The country with the highest rate of T1DM is __________.

Answer 19

Finland

Question 20

What molecule mediates beta-oxidation of free fatty acids?

Answer 20

Hormone-sensitive lipase

Question 21

Parenteral insulin has not been shown to ____________.

Answer 21

delay onset of symptoms