What is measured in thyroid function tests?
TSH
T3
T4
What is the ratio of T3 and T4 produced by the thyroid?
T4:T3 is 20:1
T3 is produced by peripheral conversion of T4
Free T4 makes up …….% of total T4, with the rest being bound to thyroid binding globulin.
1%
What clinical features are found in Grave’s disease?
Exophthalmos
Pretibial myxoedema
What will the TFTs be in hypothyroidism?
TSH high
T4 low
(if T4 is normal and TSH is raised, this suggests subclinical hypothyroidism)
What will the TFTs be in secondary hypothyroidism (pathology of pituitary or hypothalamus)?
TSH normal/low
T4 low
What will the TFTs be in Grave’s disease?
TSH low
T3 and T4 high
Why are LFTs ordered?
2. Distinguish between hepatocellular injury and cholestasis
Which blood tests are included in LFTs?
ALT AST ALP GGT Bilirubin Albumin Prothrombin time (PT)
What are the causes of an isolated rise in ALP?
If a patient has dark urine and normal stools, what does this suggest about the cause of jaundice?
Hepatic jaundice
If a patient has dark urine and pale stools, what does this suggest about the cause of jaundice?
Post hepatic jaundice (obstructive)
What can cause LOW albumin levels?
If ALT>AST what does this sugguest?
Chronic liver disease
NAFLD
Drug/ viral hepatitis
If AST> ALT what does this suggest?
Alcoholic hepatitis
Cirrhosis
Cancer
What are common causes of ACUTE hepatocellular injury?
What are common causes of CHRONIC hepatocellular injury?
What are LESS common causes of CHRONIC hepatocellular injury?
What does a typical liver screen involve?
What blood tests will be done if a patient is confused (confusion screen)?
What clinical observations may suggest anaemia due to active bleeding?
Hypotension
Tachycardia
What lab tests should be done to investigate anaemia?
What blood tests should be done to investigate hyponatraemia?
What lab tests are done in a myeloma screen?