Diabetes and Endocrine Disease Flashcards
Which cells of the pancreas produce insulin?
Beta cells (in the Islets of Langerhans)
What is C peptide?
A by-product of insulin production used as a measure of endogenous insulin.
What metabolic processes in the liver are promoted by glucagon? (2)
Glycogenolysis and gluconeogenesis
Name three conditions that Graves’ disease is associated with.
Type 1 diabetes
Vitiligo
Alopecia areata
What is candidal balanitis?
A fungal infection of the male genitalia caused by Candida yeast.
What is balanitis circinata?
A skin condition associated with reactive arthritis which presents with ring-shaped dermatitis on the glans penis.
What is Balanitis Xerotica Albicans?
Lichen sclerosis affecting the male genitals.
What are the criteria for diagnosis of diabetes mellitus in a symptomatic patient? (3)
-HbA1c of 48 mmol/mol (6.5%) or more (diagnostic for type 2 only)
OR
-Fasting Glucose Test greater than or equal to 7
OR
-Random Glucose Test greater than or equal to 11.1
How do the criteria for diagnosis of diabetes mellitus change in an asymptomatic patient?
Same criteria as given for symptomatic patients, but must be met on 2 separate occasions.
[WHO suggests this is on a ‘subsequent day’. In practice a HbA1C is often used to confirm diagnosis.]
When should you not use HbA1c results for diagnosing diabetes? (6)
-In children or young people less than 18 years of age
-Pregnant women/women 2 months postpartum.
-Patient with symptoms of diabetes for < 2 months.
-Acutely ill patients.
-Patients taking medication that may cause hyperglycaemia
-People with acute pancreatic damage (including pancreatic surgery), end-stage renal disease (ESRD), or HIV infection)
What are the hallmark symptoms of type 2 diabetes mellitus? (5)
-Tiredness
-Polydipsia/polyuria
-Increased hunger
-Unintentional weight loss
-Blurred vision
What is acanthosis nigricans?
Areas of dark skin (e.g in armpits/neck) sometimes seen in asymptomatic T2DM patients due to insulin resistance.
What is type 1 diabetes mellitus?
A condition in which the body doesn’t make enough insulin, due to a type IV hypersensitivity response where a person’s own T cells attack beta cells in the pancreas, destroying them.
What is type 2 diabetes mellitus?
A condition in which the body still makes insulin, but the tissues don’t respond well to it (reason not fully understood but to do with insulin resistance). Beta cell hypertrophy and hyperplasia initially cause increased insulin production, however this is not sustainable and beta cells eventually decrease, causing decreased insulin and increased blood glucose.
What are the roles of insulin and glucagon respectively?
-Insulin = lowers blood glucose levels by aiding transportation of it from the blood into cells
-Glucagon = increases blood glucose levels by causing generation of new glucose molecules by the liver and breakdown of glycogen into glucose to allow it to be moved into the blood
What causes polyuria in diabetes?
Hyperglycaemia in diabetes leads to glucose ‘leaking’ into the urine when blood is filtered through the kidneys; because glucose is osmotically active, water tends to follow it, resulting in an increase in urination.
What is diabetic ketoacidosis (DKA)?
A severe lack of insulin in the body means cells can’t use glucose for energy, so begin to use fat instead; this process leads to release of ketones, which can build up and make the blood acidic.
What are the classical symptoms of diabetic ketoacidosis (DKA)? (6)
-Polyuria/polydipsia
-Nausea and vomiting
-Weight loss
-Acetone smelling breath
-Dehydration (and subsequent hypotension)
-Altered consciousness
How is diabetic ketoacidosis (DKA) treated? (3)
-IV fluids (for dehydration)
-Insulin (to lower blood glucose)
-Electrolyte replacement (i.e potassium) as required
Which cells of the pancreas produce glucagon?
Alpha cells (in the Islets of Langerhans)
What is hyperosmolar hyperglycaemia syndrome (HHS)?
A state of illness and dehydration which occurs gradually over several days in people with type 2 diabetes, due to very high blood glucose levels (often >40mmol/L) resulting in a subsequent increased plasma osmolarity (and therefore decreased water in cells as it is all moving to the serum).
[Hyperglycaemia with profound dehydration and an absence of ketosis.]
What are the classical symptoms of hyperosmolar hyperglycaemia syndrome (HHS)? (4)
-Polydipsia/polyuria
-Nausea
-Dry skin
-Disorientation and, in later stages, drowsiness and loss of consciousness
What is involved in a fasting glucose test?
Patient doesn’t eat or drink (except water) for 8 hours, and then has blood glucose levels measured.
What is involved in a non-fasting or random glucose test?
Serum glucose is measured at any time, without the need for fasting or preparation for the test.
What is involved in an oral glucose tolerance test?
Patient fasts for at least 8 hours and venous fasting glucose is taken, then 150g of glucose is given and venous plasma glucose is measured two hours later.
What is an HbA1c test?
A test which looks at proportion of haemoglobin in the blood with glucose stuck to it, to measure average blood sugar over the last few months.
What are the classical symptoms of mild hypoglycaemia? (3)
Weakness
Hunger
Shaking
What are the classical symptoms of severe hypoglycaemia? (2)
Loss of consciousness
Seizures
What is checked at an Annual Diabetic Review? (6)
-Foot examination (for neuropathy and ulcers)
-Urine (raised ACR can be sign of early diabetic nephropathy)
-Cholesterol and BP (for managing CVD risk)
-Height and weight (BMI)
-Blood sugars and HbA1c (to assess diabetic control)
-Eye tests (to screen for diabetic retinopathy)
What is the first line medical therapy for type 2 diabetes?
Metformin - a biguanide which has the dual effect of increasing insulin sensitivity and decreasing hepatic gluconeogenesis.
What is the most common side effect of metformin, and how can it be reduced?
Gastrointestinal disturbance - taking metformin with meals or using modified release preparations can reduce GI side effects.