Diabetes Flashcards
Which type of diabetes is more common?
Type 2
What is the function of insulin?
- Stimulates GLUT4 to transport glucose
- Inhibits LPL from converting fatty acids to acetyl-CoA
What is the difference between Type 1 and Type 2 Diabetes?
Type 1:
Severe insulin deficiency secondary to destruction of beta cells of the pancreas
Type 2:
Disease of insulin resistance and relative insulin deficiency from beta cell dysfunction
What are the risk factors for diabetes?
Type 1:
1. Family history
2. Being younger at diagnosis
Type 2:
1. Having a close family member with DM2
2. High blood pressure, cholesterol
3. Being overweight
How is the heritability of DM1 compared to DM2?
Type 1
Variable heritability - if identical twin gets DM1, twin has less than 100% chance of getting DM1 but higher than general population
Type 2
1. If parent has DM2 - child has 40% lifetime risk of developing DM2
2. If identical twin has DM2 - twin has 70-80% risk of developing DM2
3. Environmental factors play a role - diet, physical activity
What is the
a) age of onset
b) onset
c) body habitus
d) insulin production
e) C-peptide
f) family history of diabetes
g) ketosis prone
in DM1 compared to DM2?
a) DM1 - childhood/young adult
DM2 - middle age/elderly, but incidence increasing in teens
b) DM1 - acute, presents with DKA
DM2 - gradual
c) DM1 - lean
DM2 - overweight
d) DM1 - absent
DM2 - present
e) DM1 - absent/low
DM2 - present/increased
f) DM1 - not common
DM2 - common
g) DM1 - usually
DM2 - usually not
What are the clinical features of acute diabetes?
- DKA
- Abdominal pain, nausea, vomiting
- Dehydration
- High glucose concentrations
- Increased ketones
- Low arterial/venous pH
What are the clinical features of insidious diabetes?
- Polyuria
- Polydipsia
- Polyphagia
Pee more, drink more, eat more
How is DM2 screened?
Screen every 3 yrs in patients who are > 40 yo or earlier/more frequently in high risk patients
How is diabetes defined?
- Fasting plasma glucose > 7 mmol/L
- HbA1c in adults > 6.5%
- OGTT > 11.1 mmol/L
- Random blood glucose > 11.1 mmol/L
If a patient has symptoms of diabetes, a single test is sufficient. If not, repeat test again on a different day.
How do we test for gestational diabetes?
50 g OGTT, if result inconclusive 75 g OGTT
Who to screen for gestational diabetes?
All pregnant women between GA 24-28 wk
What are the reference ranges for
a) Impaired fasting glucose
b) 2 hour OGTT (75g)
c) HbA1c
in “pre-diabetes”
a) 6.1-6.9 mmol/L
b) 7.8-11 mmol/L
c) 6-6.4%
What is the lab’s role in the diagnosis and management of diabetes?
Diagnosis
1. Fasting plasma glucose
2. Random glucose
3. OGTT
4. A1c
Management
1. POC glucometer
2. Albumin to creatinine ratio
3. B-hydroxybutyrate
4. Cholesterol panel
How to measure blood glucose?
- POC
- personal devices and hospital POC meters
- use capillary whole blood sample
- glucose oxidase/glucose dehydrogenase - Plasma/Serum/Whole blood
Glucose oxidase
Hexokinase
Glucose dehydrogenase
What are the disadvantages of measuring fasting plasma glucose?
- Patient has to fast for 8 hours
- Less sensitive than OGTT
- A large amount of variability exists
- Intraindividual CVs 4.6-8.3%
- Interindividual CVs 7.5-12.5%
What are the cautions when measuring glucose?
- Plasma/serum glucose is 10-15% higher than whole blood glucose due to higher water content
- Need to analyze sample promptly
- Cell metabolize glucose at 0.4 mm/L/hr