Hyper- and Hypoglycaemia

Question 1

How is diabetes mellitus diagnosed?

Answer 1

Either typical symptoms plus one of: fasting glucose >7, OGTT >11.1, random glucose >11.1, HbA1c >48
Or two of these tests in the absence of symptoms

Question 2

What is impaired glucose tolerance?

Answer 2

Random blood glucose or OGTT result <11.1 but >7.8

Question 3

What is impaired fasting glucose?

Answer 3

Fasting glucose >6.1 but <7.0

Question 4

What are the criteria for hyperosmolar hyperglycaemic state?

Answer 4

pH >7.3, osmolarity >320mOsm, blood glucose >30mM

Question 5

What are the clinical features of hyperosmolar hyperglycaemic state?

Answer 5

Acutely unwell with confusion and dehydration of up to 20% of body weight

Question 6

What are the causes of hyperglycaemia?

Answer 6

Corticotrophic, somatotrophic (e.g. gigantism, acromegaly), catecholamingeric, insulin resistance or deficiency

Question 7

How is hyperosmolar hyperglycaemic state managed?

Answer 7

Fluid replacement with 0.9% saline - 3-6l over 12h depending on weight and extent of dehydration (aiming to reduce glucose no more than 5mM/h and sodium by no more than 10mM/24h). Monitor with serial U&Es and glucose readings. Insulin can be used if glucose stops falling with fluids alone (0.05u/kg/hr fixed dose)

Question 8

What are the criteria for diabetic ketoacidosis?

Answer 8

pH <7.3, plasma glucose >11mM, blood ketones >3mM, urine ketones at least 2+

Question 9

What are the clinical features of diabetic ketoacidosis?

Answer 9

Rapid-onset collapse, confusion, shock - may be associated Kussmaul breathing, abdominal pain, nausea, vomiting

Question 10

Give at least 3 precipitants of diabetic ketoacidosis

Answer 10

Infection, surgery, missed insulin dose, trauma

Question 11

How much of their bodyweight can patients with DKA lose in water?

Answer 11

10%

Question 12

How is DKA managed?

Answer 12

IV access, blood gas inc ketones and glucose, IV fluids (0.9% saline), insulin (if hypokalaemic replace potassium first) 0.1u/kg/hr fixed dose regimen, maintain background basal insulin, catheterisation to monitor urine output

Question 13

State three causes of hyperinsulinaemic hypoglycaemia

Answer 13

Iatrogenic insulin, sulphonylurea excess, insulinoma

Question 14

State three causes of hypoinsulinaemic hypoglycaemia with ketones

Answer 14

Alcohol binge with no food, pituitary insufficiency, Addison’s disease, liver failure, fasting, anorexia nervosa

Question 15

State two causes of hypoinsulinaemic hypoglycaemia with no ketones

Answer 15

Tumours causing a paraneoplastic syndrome, fibrosarcomata, fibromata

Question 16

State two causes of hypoinsulinaemic hypoglycaemia with ketones in neonates

Answer 16

Prematurity, intrauterine growth restriction

Question 17

State a cause of hypoinsulinaemic hypoglycaemia with no ketones in neonates

Answer 17

Inherited metabolic disorder