EMQ on Enzymes, chemistry Flashcards
Which one is increased in a patient with Paget’s disease of the bone?
C. ALP
Pagets is a bone turnover disease, and there is both increased osteoblast and osteoclast activity
Sabre/bowed tibia - weak bones with a high risk of fracture
Treatment is a bisphosphonate - make bone with calcium and phosphate - make it with calcium and bisphosphonate lasts longer and removes pain from pagets.
Which one is increased in a patient with osteomalacia?
c. ALP
Osteomalacia is caused by a lack of vitamin D. This results in secondary hyperparathyroidism, which in turn attempts to stimulate bone formation.
ALP is high due to high bone turnover
Which one is increased in a patient following an acute myocardial infarction?
D. AST - leaks out of muscle
Also: released from damaged muscles:
Troponins - stay high for a while after the event
CK (MB) - goes up - MB fraction is from the heart. (CK BB is from the brain)
AST - 3 days - 14 days after MI
LDH
Which one is raised in Addison’s disease?
- Potassium
hyperkalaemia and hyponatraemia
Which one of the above is most increased in a patient with jaundice caused by a gallstone?
c. alkaline phosphatase
obstructive jaundice - the alk phos goes up. The liver is arranged in hexagons with a central vein, portal vein and hepatic artery. Clean blood goes into the central vein. Blood is cleaned by interaction with the biliary tree branches.
High alk phosp around the bile duct so goes up when pressure is around that area
Different areas of the zones damage release different enzymes
Which one is most increased in a patient with jaundice caused by viral hepatitis/inflamed hepatocytes?:
B.ALT
ALT when virus is invading and inflaming hepatocytes
Virus affects the central part of the liver hexagon, where there is mainly ALT. So ALT goes up in viral hepatitis
Which one is most increased in a patient with jaundice caused by chronic alcoholic cirrhosis?
d. AST
when cells regenerate in the liver, they don’t form the normal hexagon shape, they instead form like spheres and form nodules. eventually with chronic alcohol consumption, more nodules occur and the liver shrinks.
The route for blood to flow through the portal triad to the central vein in the liver then becomes so messed up when there are loads of nodules, portal hypertension occurs and this leads to varicies. The last cells able to make enzymes make AST.
Which one is most increased in a patient with prostatic carcinoma?
a. Acid phosphatase (PSA)
Which one is raised in primary hyperparathyroidism?
E. Calcium
Which one is low in primary hyperparathyroidism?
- Vitamin D
Vit D is low as it is consumed quickly when there is high PTH as PTH is involved in the vitamin D pathway
Which one rises most in acute renal failure, where the cause is dehydration?
- urea
Normal kidneys, all normal, but urea is high as trying to keep water
Sodium will rise, but urea will rise MORE
Which one rises most in chronic renal failure, caused by a fall in GFR?
- Creatinine
Good marker for GFR
In diabetes once they have a creatinine 200, CKD develops rapidly
Poor urine quality, but Na, K are all normal
Which one is a marker of glucose control over the last three months?
- HbA1c
Name a scan to look at each of the following things:
- Abdominal mets from cancer
- Bony mets
- Primary Neuroendocrine tumours (insulinomas)
- Thyroid scans
- Parathyroid scans
- phaeochromocytomas
- Abdominal mets from cancer - FDG-PET
- Bony mets - Tc bisphosphonate
- Primary Neuroendocrine tumours (insulinomas) - Gallium 68 dotatate
- Thyroid scans - Tc 99 pertechenate
- Parathyroid scans - Sesta MIBI
- phaeochromocytomas - MIBG
What are the indications for dialysis in someone with creatinine of >200?
Indications for dialysis when creatinine is >200
- Hyperkalaemia
- Acidosis (try bicarbonates first)
- Pulmonary oedema
Which one is a marker of glucose control over the last 3 weeks?
- Fructosamine
Be used in obstetrics to improve outcomes. Needed quicker so HbA1c not as useful. Also as pregnancy continues, insulin resistance worsens, so a quicker assessment that is more recent is needed.
Freestyle libre may be the future checking and monitoring blood glucose constantly
