Diabetes Flashcards
What cells in the pancreas secrete insulin
beta cells in islets of langerhans
What does insulin do
Lowers blood sugar by:
- causing cells to absorb glucose to use as fuel
- causing muscles + the liver to absorb glucose and store as glycogen
what cells in the pancreas secrete glucagon
alpha cells in islets of langerhans
what does glucagon do
Raises blood sugar by:
- causing stored glycogen in liver to break down into glucose – glycogenolysis
- causing liver to convert protein + fats into glucose – gluconeogenesis
how are ketones produced
liver converts fatty acids to ketones
- occurs when there is insufficient glucose and glycogen stores have been depleted
what is type 1 diabetes
autoimmune destruction of beta cells in the islets of langerhans leading to absolute insulin deficiency
triad of symptoms in T1DM
polyuria
polydipsia
weight loss
antibodies in T1DM
Anti-islet cell Ab
Anti-GAD antibody
what is type 2 diabetes
insulin resistance + impaired insulin production causing hyperglycaemia
modifiable risk factors for T2DM
Obesity
Sedentary lifestyle
High carbohydrate diet
HbA1c diagnostic of diabetes
> 48mmol/L (6.5%)
diagnosis of diabetes using
- random blood glucose
- fasting blood glucose
random - >11.1mmol/L
fasting - >7 mol/L
-Once is enough if symptomatic
-If asymptomatic these results must be seen on 2 occasions for a diagnosis of diabetes
what is pre-diabetes
indication that patient is heading towards diabetes but does not meet full diagnostic criteria
- should be educated on lifestyle modifications to decrease risk of progressing to diabetes
HbA1c range indicative of pre-diabetes
42-47 mmol/L
what test can pick up pre-diabetes
Oral Glucose tolerance test
what is an Oral glucose tolerance test
75g glucose given to a fasting patient, baseline glucose + glucose 2 hours after drink measured
result showing impaired glucose tolerance on OGTT
plasma glucose 7.8-11 after 2 hours
- Body struggles to cope with processing a carbohydrate meal
result showing diabetes on OGTT
glucose >11 after 2 hours
what is a normal fasting glucose level
<6 mmol/L
what is an impaired fasting glucose level
6.1 -6.9 mmol/L
what is a fasting glucose level indicative of diabetes
> 7mmol/L
what is MODY
development of T2DM in patients <25 years old
inheritance of MODY
autosomal dominant
most common genetic defect in MODY
defect HNF-1 alpha gene (MODY 3)
treatment of MODY
responsive to sulfonylureas
What is latent autoimmune diabetes of adulthood (LADA)
Type 1 diabetes presenting in later life
- low c peptide
- antibody positive
- requires insulin
treatment of pre-diabetes
lifestyle
- weight loss
- smoking cessation
- low glycemic diet
1st line tx T2DM
metformin
2nd line tx T2DM
metformin + Sulfonylurea / pioglitazone / DPP4 inhibitor / SGLT-2 inhibitor
3rd line tx T2DM
- metformin + 2 other diabetic drugs (triple therapy) OR
2. metformin + insulin
in a patient on metformin, what HbA1c measurement requires addition of another drug
when HbA1c reaches 58mmol/L
what can cause a higher than expected HbA1c
things that increase RBC life span:
- splenectomy
- Vit B12/folic acid deficiency
- Iron deficiency anaemia
what can cause a lower than expected HbA1c
things that lower RBC life span:
- sickle cell anaemia
- G6PD deficiency
- hereditary spherocytosis
what drug can cause impaired glucose regulation
steroids
