Hypoglycaemia Flashcards
What is the definition of hypoglycaemia
Defined as a blood glucose of below 4mM
What are the signs of hypoglycaemia
a phase of sweating, tachycardia and agitation due to activation of the sympathetic nervous system and release of adrenaline and glucagon.
What are the symptoms of hypoglycaemia on the brain
moodiness, faintness, numbness in arms and hand, blurred vision etc may lead to coma.
what is the critical concentration of blood glucose
2.5mM, this is where the loss of consciousness occurs. rapid restoration of blood glucose is vital.
What is alcohol-induced hypoglycaemia
Develops several hours after alcohol ingestion, occurs when glycogen stores are depleted, consumption of alcohol puts additional stress on gluconeogenesis and it may be decreased by liver damage.
How does alcohol result in hypoglycaemia
The breakdown of alcohol gives NADH which is the product of many reactions in the glycolytic pathway however due to its high quantities the equilibrium of the reactions will shift to the LHS e.g.
lactate + NAD pyruvate + NADH + H
What are the long term consequences of alcohol consumption
high levels of NADH inhibits fatty acid oxidation instead fatty acid synthesis takes place and TAG’s accumulate in the liver causing a condition known as fatty liver.
hepatomegaly: leads to accumulation of protein which causes enlargement of the liver.
What are some side problems with chronic alcoholics
Deficient in intake of macronutrients e.g. vitamins, folate and minerals. 50% of alcoholics with liver disease will have a thiamine deficiency. this is due to ethanol interfering with GI absorption and hepatic dysfunction which hinders storage and activation of thiamine pyrophosphate
What is the role of thiamine
It is a cofactor for many enzymes and it has a very short half-life of 10-20 days so a deficiency can arise quickly.
What do glycogen storage diseases affect, how many types are there?
Glycogen storage diseases affect the enzymes in the stages of glycogen synthesis and breakdown. They are very rare and there are 5 types.
What enzyme does each type of glycogen storage disease effect
type 0: glycogen synthase type 1: G6Pase type 3: debranching enzyme type 4: branching enzyme type 5: glycogen phosphorylase
Outline type 1 GSD
Von Gierke’s disease affects mainly the liver and kidneys caused by a deficiency in G6Phosphotase which leads to an excess of G6P and leads to storage of excess of glycogen and liver enlargement.
Outline type 2 GSD
Pompe’s disease, a deficiency of a-1,4 glucosidase activity in the lysosomes. can be one of the most devastating, causing death by cardiorespiratory failure
Outline type 3 GSD
Cori’s disease, an amylo 1,6 glucosidase deficiency unable to break down glycogen resulting in hypoglycaemia. Symptoms disappear at puberty
Outline type 4 GSD
Andersen’s disease, one of the most severe. liver in the glycogen is unbranched that have low solubility and don’t live beyond 4 years
