Blood tests

Question 1

serum

Answer 1

formed when blood is allowed to coagulate in test tube
cant take cell count as is congealed together

removed fibrinogen and fibrin from blood clot

Question 2

plasma

Answer 2

uncoagulated
inhibit coagulation by using additives in collection of blood:

adding EDTA (calcium chelator)
heparin
oxelade
fluoride
inhibits lost of enzyme systems

Question 3

separate blood process

Answer 3

centrifuge
red
white
platelets
plasma/serum on top

2-4 hours

Question 4

blood test categories

Answer 4

clinical biochemistry- looking at plasma/serum
kidney, liver function, immune, blood sugar

haematology:
full blood count

virology:
viral assays measuring rna or dna, serology (antibodies)

immunology:
autoantibody screenings

microbiology:
serology, bacterial RNA, blood cultures

Question 5

serum sodium

Answer 5

hyponatremia:
due to excess water, dilutional hyponatremia
cirrhosis with salt and water retention
sodium loss in urine (addison’s)
thiazide diuretics

Hypernatraemia
deficit of water relative to sodium
dehydration

Question 6

serum potassium

Answer 6

risk of cardiac arrhythmias

hypo:
diuretics
diarrhoea
aldosterone excess
underlying endocrine disorder

hyper:
AKI
certain drugs

Question 7

urea

Answer 7

breakdown of proteins

low:
alcoholics, excess fluids

high:
dehydration,
renal hypoperfusion
AKI or chronic

high urea:creatinine ratio means dehydration

Question 8

creatinine

Answer 8

breakdown product of creatine phosphate (source of atp)
less muscle, less serum creatinine

high:
AKI/ chronic

low:
low protein intake
muscle wasting

Question 9

bilirubin

Answer 9

high:
jaundice
hemolysis
liver disease
biliary obstruction

Question 10

albumin

Answer 10

low:
infection
nephrotic syndrome
severe liver disease
severe malnutrition`

Question 11

ALT

Answer 11

moderately high:
fatty liver
cholangitis
v high:
liver cell injury
acute viral hepatitis

<AST:
alcohol excess, severe fibrosis/cirrhosis, muscle injury`

Question 12

alkaline phosphotase

Answer 12

high:
pregnancy
bone disease
biliary obstruction
primary sclerosing/biliary cholangitis

Question 13

full blood count
haemoglobin

Answer 13

low:
anaemia:
iron deficiency
chronic disease
haemolysis
B12/folate deficiency

high:
polycythaemia (due to COPD):
primary/secondary

Question 14

neutrophilia

Answer 14

high:
bacterial infection

Question 15

lymphocytes

Answer 15

high:
viral infection

Question 16

platelet count

Answer 16

high:
thrombocytosis
chronic inflammation
bone marrow disorder

low:
consumption in spleen
consumption due to disseminated intravascular coagulation
immune mediated
cirrhosis

Question 17

mean cell volume

Answer 17

low:
iron deficiency

high:
B12/folate deficiency
haemolysis
alcohol misuse
liver disease

Question 18

iron and ferratin

Answer 18

low iron:
suggests iron deficiency

only if ferratin also low

ferratin:
high:
infection/inflammation
alcohol misuse

Question 19

diabetes tests

Answer 19

fasting glucose
elevated random glucose
urinalysis for glucose/ketones
HBA1c level
glucose tolerance test

Question 20

HBA1c

Answer 20

high: chronic hyperglycaemia

low:
haemolysis

Question 21

lipid tests

Answer 21

cholesterol LDL HDL

triglycerides VLDL

high:
hyperlipidaemia
hypercholesterolemia
premature myocardial infarction

Question 22

T4 T3 TSH

Answer 22

low:
stimulates pituitary,
increased synthesis

high:
suppresses pituitary, decreases synthesis

low T4 and high TSH:
hypothyroidism

high T4 and low TSH
hyperthyroidism

Question 23

creatine kinase

Answer 23

high:
myositis
muscle injury
rhabdomyolysis
myocardial infarction

Question 24

biomarkers of muscle injury

Answer 24

creatine kinase
myoglobin
troponin
aspartate transaminase