Chemical Pathology - Hypoglycaemia Flashcards
What is the cut-off for hypoglycaemia?
Glucose <4mmol/L
What are hyperinsulinaemic causes of hypoglycaemia?
- Insulin overdose
- Sulfonylureas
- Insulinomas
What are hypoinsulinaemic causes of hypoglycaemia, with positive ketones?
- Alcohol binge with no food
- Pituitary insufficiency
- Addison’s
- Liver failure
What are hypoinsulinaemic causes of hypoglycaemia, with negative ketones?
Non-pancreatic neplasms:
- Fibrosarcomata
- Fibromata
What are the general investigations for hypoglycaemia?
- Insulin
- C-peptide
- Ketones
What are non-islet tumours causing hypoglycaemia, and their investigative findings?
- Tumours that cause paraneoplastic syndrome, secreting IGF-2 which binds to IGF-1 + insulin receptors
- Decreased glucose
- Decreased insulin
- Decreased C-peptide
- Decreased FFA
- Decreased Ketones
What is endogenous insulin secretion?
- When insulin + C-peptide levels are both high
- Insulin:C-peptide = 1:1
What is exogenous insulin secretion?
When insulin levels are high but C-peptide levels are low
- Insulin:C-peptide = >1:1
What is the general treatment for a hypoglycaemic patient who is alert + orientated?
PO carbohydrates
- Rapid acting = juice + sweets
- Longer acting = sandwiches
What is the general treatment for a hypoglycaemic patient who is drowsy/confused, but their swallow is intact?
Buccal glucose:
= Glucogel
What is the general treatment for a hypoglycaemic patient who is unconscious/concerned about swallow?
- IV 100ml 20% dextrose
What is the general treatment for hypoglycaemia that is insulin-induced/refractory/deteriorating/difficult IV access?
- IM/SC 1mg glucagon
Must have adequate glycogen stores NOT:
- Starving
- Liver failure
- Anorexia nervosa
What are some general causes of hypoinsulinaemic hypoglycaemia in an adult?
- Fasting
- Strenuous exercise
- Critical illness
- Endo deficiency (hypopit, adrenal failure)
- Liver failure
- Anorexia nervosa
HIGH FFAs + HIGH KETONES
What are soem general causes of hypoinsulinaemic hypoglycaemia in a neonate?
Ketones + FFAs:
- Premature
- IUGR
- Co-morbidity
NO KETONES + FFAs:
- Inherited metabolic disorder
