Endocrinology Flashcards
(204 cards)
What is the pathophysiology of Type 1 diabetes mellitus (T1DM)?
T1DM is a form of diabetes that develops due to immune-mediated destruction of insulin-producing pancreatic beta cells. Without insulin, the body’s cells ‘starve’.
What age does T1DM typically develop?
Typically in people under the age of 25 years.
How does T1DM present?
Most commonly fatigue, polyuria, polydipsia and weight loss.
Over what time period does T1DM develop over?
Can develop over weeks to months.
Some T1DM patients may present critically with what condition?
Diabetic ketoacidosis.
How is T1DM diagnosed?
Finger-prick glucose monitor.
HbA1c.
What are the diagnostic thresholds for fasting and random blood glucose in symptomatic individuals ?diabetes mellitus?
Fasting glucose ≥ 7.0mmol/L.
Random blood glucose ≥ 11.0mmol/L.
What are the diagnostic thresholds for fasting and random blood glucose in asymptomatic individuals ?diabetes mellitus?
Fasting glucose ≥ 7.0mmol/L.
Random blood glucose ≥ 11.0mmol/L.
Demonstrated on two separate occasions.
What are the diagnostic thresholds for HbA1c in symptomatic individuals ?diabetes mellitus?
HbA1c ≥ 48mmol/mol.
What is HbA1c?
Glycated haemoglobin that reflects average blood glucose levels over the previous two-three months.
How is T1DM managed?
With regular monitoring of blood glucose and lifelong daily subcutaneous insulin injections.
By what route is insulin administered and where?
Subcutaneously typically at the stomach, thighs or buttocks.
What are side effects of subcutaneous insulin use?
Injection bruises (rupturing a small capillary when injecting), injection lumps (repeatedly injecting at the same site too often), weight gain and hypoglycaemic episodes.
What increases the risk of hypoglycaemic episodes during insulin use?
Imbalance of insulin in relation to food consumed and physical activity undertaken (missing a meal, not eating enough carbohydrates, doing lots of exercise, taking more insulin than needed).
Give four types of insulin.
Rapid-acting insulin (before or after meals).
Mixed insulin (mixture of short-acting and long-acting insulin, the number in the name indicates the % that is short-acting).
Intermediate-acting insulin (background insulin taken once or twice a day).
Long-acting insulin (even slower than intermediate and can be taken once per day).
What is typical strength of insulin (units/ml)?
100 units/ml.
What is diabetic ketoacidosis (DKA)?
A life-threatening complications of diabetes that occurs due to insufficient insulin.
How does DKA present?
Abdominal pain, vomiting and reduced consciousness. Patient may also have a high respiratory rate.
What precipitates DKA?
Typically precipitated by an illness or stressor. Can occur due to failure to take insulin (more common in the young and vulnerable e.g. homeless).
What investigations should be ordered/undertaken in a patient with suspected DKA?
Plasma glucose.
ABG.
Capillary or serum ketones.
Urinalysis.
What does plasma glucose reveal in a patient with DKA?
Blood glucose level > 11mmol/L.
What does ABG reveal in a patient with DKA?
Metabolic acidosis.
What does serum ketones reveal in a patient with DKA?
Ketonaemia > 3mmol/L.
What does urinalysis reveal in a patient with DKA?
Positive for glucose (glycosuria) and ketones (ketonuria).