Hypoglycaemia (E&M)

Question 1

Define hypoglycaemia.

Answer 1

Clinical syndrome present when BGC falls below the normal fasting glucose range, generally <3.3mmol/L

Question 2

What is Whipple’s Triad (hypoglycaemia)?

Answer 2

• low BGC
• hypoglycaemic symptoms
• resolution of symptoms after raising BGC to normal

Question 3

What are some causes of hypoglycaemia? (7)

Answer 3

• diabetes - insulin/sulfonylurea use, fasting/missing meals
• drug causes - sulfonylureas and insulin, SGLT-2 inhibitors, DPP-4 inhibitors
• hormone deficiency causes - hypopituitarism, adrenal insufficiency (Addison’s disease), GH deficiency
• insulinoma - excessive secretion of insulin due to pancreatic tumour
• liver failure
• sepsis
• post-prandial hypoglycaemia in malnourished individuals

Question 4

What happens if you administer exogenous insulin (stress test) in insulinoma (hypoglycaemia)?

Answer 4

C-peptide does not fall

Question 5

Which tumours have been reported to secrete IGF-II?

Answer 5

Sarcomas, fibromas, fibrosarcomas and renal cell carcinomas

Question 6

What are the most worrying causes of hypoglycaemia? (2)

Answer 6

• insulinoma
• tumour-related hypoglycaemia

Question 7

What are the three groups of clinical features seen in hypoglycaemia?

Answer 7

• increased sympathetic activity
• increased parasympathetic activity
• neuroglycopenic symptoms

Question 8

What features of increased sympathetic activity are seen in hypoglycaemia? (6)

Answer 8

• sweating
• anxiety
• tachycardia
• tremor
• palpitations
• pallor

Question 9

What features of increased parasympathetic activity are seen in hypoglycaemia? (4)

Answer 9

• hunger
• nausea
• vomiting
• paraesthesia

Question 10

What neuroglycopenic symptoms are seen in hypoglycaemia? (3)

Answer 10

• confusion
• seizures
• agitation

Question 11

What are some risk factors for hypoglycaemia? (4)

Answer 11

• middle age
• female sex
• insulinoma
• exogenous insulin

Question 12

What are the first-line investigations in hypoglycaemia?

Answer 12

• serum glucose
• LFTs
• renal function
• serum insulin and C-peptide

Question 13

What serum glucose levels might we see in hypoglycaemia? (2)

Answer 13

• <3.3mmol/L –> autonomic symptoms
• <2.8mmol/L –> neuroglycopenic symptoms

Question 14

What does raised serum insulin indicate?

Answer 14

Insulinoma

Question 15

What C-peptide levels might we see in hypoglycaemia? (2)

Answer 15

• elevated if endogenous insulin –> insulinoma
• low if exogenous insulin

Question 16

Why do we check serum cortisol in hypoglycaemia?

Answer 16

Looking for adrenal insufficiency

Question 17

When do we check BGC in patients in general?

Answer 17

In any patient presenting with confusion/neurological symptoms

Question 18

How do we manage hypoglycaemia if patient conscious and able to swallow?

Answer 18

Oral glucose 15-20g (liquid, gel or tablet) + fast-acting carbohydrates (glucose tablets, sweets, juice, starchy snack)

Question 19

How do we manage hypoglycaemia if patient unconscious?

Answer 19

1mg IM glucagon (takes hours to work) + IV dextrose (20% glucose - more rapid, or if glucagon does not improve Sx)

Question 20

How do we manage hypoglycaemia with impaired GCS?

Answer 20

IV glucose if there is access e.g. cannula (50ml of 50% glucose IV)

or 1mg IM glucagon

Question 21

How do we manage hypoglycaemia if overdose, toxin or ethanol-related?

Answer 21

Supportive care, psychiatric evaluation and treatment

Question 22

How do we manage hypoglycaemia due to insulinoma? (4)

Answer 22

• surgical excision
• medical therapy
• embolisation
• chemotherapy

Question 23

How do we manage hypoglycaemia due to IGF-II secreting tumour?

Answer 23

Surgical excision + chemo/radiotherapy

Question 24

How do we manage hypoglycaemia due to renal failure/liver failure/sepsis?

Answer 24

Treat underlying disease

Question 25

What are some complications of hypoglycaemia? (2)

Answer 25

• seizure
• coma