blood investigations

Question 1

bloods full blood count

Answer 1

Hb can look for any signs of anemia
mean corpuscle volume- looking for macrocytosis (heamolytic anaemia, vitamin def)
microcytosis- iron def or thalessemia

Question 2

whta re you looking for in requesting a total cholesterol for investigations with heart failure

Answer 2

LDL greater than 3 mmol
high density lipoprotein less than 1 mM
target cholesterol is less than 0.8

Question 3

what are you looking for in the HbA1c

Answer 3

looking for increased percentage of glycoylated hb

you are looking for a good diabetic control of less than 6.5 %

Question 4

what are the glucose levels in the blood that are you looking for to diagnose diabetes?

Answer 4

random greater than 11.1

fasting greater than 7.0

Question 5

brain naturetic peptide

Answer 5

hormone released by the ventricular myocytes during increased stress and strain.
It has a high negative predictive value but it has a low specificity
modest rises heart strain (PE cor pulmonale)
other diseases like in renal failure

Question 6

amylase or lipase

Answer 6

amylase 200-600 U/L caused by pancreatitis
but can be caused by pancreatic pathology: pancreatic trauma, carcinoma
intrabdominal pathology: perforated peptic ulcer, acute appendicitis, acute cholecystitis, ectopic pregnancy, pelvic inflammatory disease, mesentaric ischemia, leaking AAA
decreased amylase clearance due to renal failure or macroamylasaemia
diabetic ketoacidosis, head injury
however if the amylase levels are greater than 1000 or elevated lipase greater than 300 diagnostic of acute pancreatitis

Question 7

elevated aspartate aminotransferase (AST) and alaline aminotransferase (ALT)

Answer 7

suggests a liver pathology as these are damage hepatocytes

Question 8

raised ALP (alkaline phosphatase) and bilirubin and gamma glutamic transferase (GGT)

Answer 8

suggests a pathology in the biliary tree.
however GGT raised in isolation looks like alcohol excess
raised ALP can happen in bone pathology (or a placenta)

Question 9

albumin correlation with pancreatitis

Answer 9

prognosis indicator

Question 10

So a patient comes in with a high TSH and symptoms of hypothyroidism what test could you order to rule out Hashimotos?

Answer 10

antithyroid peroxidase antibodies elevation

Question 11

Your patient presents with the classical signs of hypercalcemia (bones, moans, groans) what investigations are you going to undertake (blood)?

Answer 11

alkaline phosphate
parathyroid hormone
phosphate
As these can help differentiate the cause of the hypercalcemia

Question 12

If the patient’s hypercalemia is due to bones mets what you expect in the bloods?

Answer 12

high alk phos because increased activity in the bone (increased turnover)
PTH would be low (as this is not a parathyroid issue)
phosphate would be high because there is increased degradation of the bones

Question 13

If the underlying cause of the patient’s hypercalcemia is myeloma what would you expect on blood investigation?

Answer 13

ALP would be normal *blast inhibition
parathyroid hormone low
phosphate will be high (due to paraprotein so it is more of a pseudophosphatemia)?

Question 14

what if you patient with hypercalemia has hyperparathyroidism?
Test results?

Answer 14

normal to high ALP increased Pth increased bone turnover
normal to high PTH
low phosphate

Question 15

if hypercalcemia is due to vit D overdose what should you be looking for?

Answer 15

ALP low
PTH low
phosphate high

Question 16

normal creatinine?

Answer 16

70-150 microM/L

Question 17

what is the normal urea?

Answer 17

2.5-6.7 mmol/L

Question 18

in the context of oligouria what does an elevated urea mean? what does an elevated creatinine mean?

Answer 18

urea solo- renal hypoperfusion

creatinine plus urea- acute kidney injury

Question 19

if you suspected the prostate hyperplasia was causing urinary obstruction what would you do?

Answer 19

arrange for a PSA (prostate specific antigen) at a later date, because it will be raised during the acute episode.

Question 20

What parts of the clotting cascade does warfarin interfere with?

Answer 20

Vitamin K competitive antagonist

II, VII, IX, X, protein C and protein S