Introduction to understunding Blood Science Results Flashcards
What is Histology?
Taking tissue samples, biopsies
What is Haematology?
diseases of the blood coagulation and blood transfusions
What is Clinical chemistry?
Chemicals in the blood urine etc
What can the analyses of samples be used for?
diagnosing disease screening for disease prognosis progression/remission of disease monitoring therapy therapeutic drug monitoring side effects of these drugs
What types of samples can be analysed in Clinical Chemistry?
Serum whole blood urine faeces sweat cerebrospinal fluid post-mortem samples miscellaneous fluids
What is measured in the fluid samples?
- Ions
- Metabolites
- waste breakdown, urea creatinine
- markers of cell damage
- enzymes (an d function)
- plasma protein
- Antibodies
- hormones
- drugs
- vitamins
- metals
What is analysed in a renal function test?
- sodium
- potassium
- urae
- creatinine
What is analysed in a liver function test ?
- total protein
- albumin
- biliubrin
- alkaline phosphatase
- alanine transaminase
What is analysed in a bone profile?
- total protein
- albumin
- calcium
- phosphate
- alkaline phosphatase
What is analysed in a thyroid function test?
- TSH (thyroid stimulating hormone)
- Free T4 (thyroxine)
What is analysed in a lipid profile ?
- total cholesterol
- HDL-cholesterol
- triglycerides
What are key things to remember about a reference range?
- some poeple can be outside this cane and be healthy- look at past tests and vice versa
- 2.5% of people are outside the reference range normally
What is creatine and what is its range pattern in the body
- waste product, amount shows how well the kidney is functioning
- varies with age and sex
- more muscle mass= ore creatinine
What are the effects of pregnancy on clinical chemistry tests?
- TSH, Thyroid stimulating hormone
- free T4, thyroxine
- free T3, triiodothyronine
change at different points in pregnancy
these gradually decrease throughout the pregnancy
Describe the control of the thyroid hormones?
- negative feedback system
What is a “normal” pattern of thyroid results
- Thyroidstimulating hormone: TSH normal is between 0.27-4.20 mU/L
- free T4 (thyroxine) normal is between 12-22 pmol/L
What is a hypothyroid pattern in a thyroid test?
- high thyroidstimulating hormone: TSH ( normal is between 0.27-4.20 mU/L)
- low free T4 (thyroxine) (normal is between 12-22 pmol/L)
What is a hyperthyroid pattern in a thyroid test?
- Low thyroidstimulating hormone: TSH ( normal is between 0.27-4.20 mU/L)
- high free T4 (thyroxine) (normal is between 12-22 pmol/L)
What can ALP- (Alkaline phosphate ) results indicate?
can be elevated in both
- liver disease
- bone disease
Potential diagnosis for: 72 yr male presenting with chest pain and a high potassium
- risk of MI
Potential diagnosis for: 54 yr female, presents in A/E feeling unwell showing signs of confusion with a low sodium level and low cortisol
- Addisonian crisis likely
acute adrenal insufficieny
Potential diagnosis for: 68yr male presents with back pain with calcium and creatinine
- risk of MI
- possible myeloma
Potential diagnosis for: 82 yr male presents with N&V in A&E with unremarkable breathing and doesn’t smell ketotic high glucose and creatinine
- hyperosmola non-ketotic coma (HONK)
- also risk of death
Potential diagnosis for: 35 yr male with abdominal discomfort and history of excess alcohol intake with high triglyceride
- risk of pancreatitis
Potential diagnosis for: 54 yr female presents with feeling unwell and tired with a low but within range TSH and a high free T4
- potential pituituary failure
Why would you treat lipid disorders which are often asymptomatic?
- to reduce the atherosclerotic process and reduce the incidences of clinical vascular disease
- to prevent pancreatitis which is associated with a grossly increased serum triglyceride
What are modifiable risk factors for cardiovascular disease?
- Smoking
- Obesity
- Sedentary lifestyle
- Excess alcohol intake
- Diabetes
- Hypertension
- high cholesterol to abnormal blood lipids
What is the site of action of statins and what is the resultant effect?
- Acts as an HMGCoA reductase Inhibitor
- prevents HMG-CoA from forming to Mevalonate, one of the pre-cursors to cholesterol
- reduces endogenous cholesterol production
What are the modifiable risk factors of Angina?
- Treatment of hypertension
- Cessation of smoking
- Weight reduction
- Control of diabetes
- Regular physical activity
- Cholesterol reduction: Initiation of statin therapy
What constitutes a significant change in cholesterol values after a course of treatment is taken?
- the Result Change Value (RCV) of the serum cholesterol needs to be 16%
What constitutes a significant change in Prostate-specific antigen (PSA) values after a course of treatment is taken?
- the Result Change Value (RCV) of the serum PSA needs to be 56%
How does lactic acidosis occur?
- usually due to tissue hypoperfusion
- leads to increased anaerobic metabolism in cells
- there is additional H+lactate- added
- H+ combines with HCO3- leaving the Na+ in serum to bind with lactate-
can also be caused by - hypokalemia, cardiac failure, sepsis, cardiopulmonary arrest
What extracellular ions are there for maintaining acid-base balance?
- Bicarbonate-, Na+
- Albumin-, Na+
What intracellular ions are there for maintaining acid-base balance?
- Haemoglobin-, K+
- Muscle protein-, K+
What is the troponin pattern after an MI?
- troponin is raised 6h after the MI
- troponin is elevated within 2-3 hrs after onset of chest pain
- peaks at 18-24 hr
- remains elevated for up to 14 days, half-life ~2 hours
When would a troponin test be requested?
- Monday after weekend chest pain
- atypical symptoms
- ECG changes none, non-specific
What could be a differential diagnosis for raised troponin?
- Heart failure
- CKD
- Pulmonary embolism
- Pericarditis acute
- Trauma - cardiac
- Cocaine
- Assay interference: autoantibodies
What could be a differential diagnosis for a raised BNP ( B type natriuretic peptide)?
- Heart: CAD, MI, AF, myocarditis
- Lung: Embolism, COAD
- Stroke
- Sepsis
- Kidney disease
- Anaemia severe
- Assay interference: autoantibodies
