Week 3: Common Lab Tests Flashcards
high C reactive protein (CRP) levels in the blood are a non-specific marker for…
inflammation
Electrolytes are minerals dissolved in the blood as …
salts
T or F
Electrolytes can only be found in blood
F
They can also be found in the tissues of the body.
What functions do electrolytes serve in the body?
moving nutrients and waste products into and out of cells, maintaining the body’s acid/base (pH) balance, and maintaining the body’s fluid balance.
high creatine kinase (CK) levels in the blood usually indicate…
muscle damage
Enzymes found in the blood can be markers of … damage or disease.
tissue
T or F
An individual’s pathology result may be outside the reference range without necessarily being indicative of a health issue requiring treatment.
T
When we are measuring kidney function, we are measuring the ability of the kidney to filter blood through the … A key measurement of kidney function therefore is the ….
glomerulus
GFR (Glomerular Filtration Rate)
T or F
Reduced kidney function is always considered chronic
F
Reduced kidney function can be an acute problem (Acute Kidney Injury – AKI) or a chronic problem (Chronic Kidney Disease – CKD) and this needs to be interpreted from the blood tests.
To estimate the rate of glomerular filtration (eGFR), blood is tested for the presence of a waste product from muscle tissue called …
creatinine.
Why is creatinine used to measure glomerular filtration rate?
- because it is produced as a breakdown product from muscle at a reliably consistent rate.
- The kidneys generally filter out between 90-95% of creatinine from the body.
T or F
Each method of estimating renal function uses the serum concentration of creatinine as a variable.
T
T or F
Tests to estimate renal function are interchangeable as they all use creatinine as a variable.
F
Acute Kidney Injury (AKI) is defined as an abrupt decrease in kidney function which encompasses both … and …
injury (structural damage) and impairment (loss of function).
ACE inhibitors are more likely to precipitate an AKI if a person is …
dehydrated
When it comes to drug causes of AKI, of significant concern is the so-called TRIPLE WHAMMY, which includes what drug classes?
The term triple whammy refers to the concurrent use of an ACE inhibitor or ARB, with a loop diuretic such as furosemide, and an NSAID (ACEi/ARB + Diuretic + NSAID)
Cardiac biomarkers used to diagnose a heart attack or heart failure can include:
Cardiac Troponin (Troponin I or Troponin T)
Creatine Kinase (CK)
Creatine Kinase-MB (CK-MB)
B-Type Natriuretic Peptide (BNP) and N-terminal-proBNP (NT-proBNP)
T or F
Cardiac biomarkers can not only be used to diagnose an MI but also indicate the level of damage.
T
Heart attack symptoms in males can include:
- sudden cold sweat
- chest pain or pressure
- shortness of breath
- nausea
- discomfort or tingling in the back, shoulder, arms, neck or jaw
What additional symptoms are more common in females?
- lightheadedness, dizziness
- chest pressure without pain
- vomiting
- a feeling of heartburn/indigestion
- extreme fatigue
- discomfort or tingling in one or both arms
*Note crossover symptoms between genders do occur
Creatine kinase is an enzyme that is found in many tissues of the body. The three isoenzyme forms include:
CK-MM (found in the heart and skeletal muscle, which makes up most of the CK in the blood)
CK-MB (found mostly in heart muscle)
CK-BB (found mostly in the brain)
antipsychotic medications have been associated with a life-threatening condition called …., which can also lead to raised CK levels.
neuroleptic malignant syndrome (NMS)
T or F
CK elevations are likely to occur following absence seizures or simple and complex partial seifibrates, antiretrovirals, ARBs, immunosuppressants and hydroxychloroquine. zures.
F
unlikely
Elevations in CK levels are common after generalised …-… seizures.
tonic-clonic
List some medication categories that have the potential to impact CK levels.
Statins, fibrates, antiretrovirals, ARBs, immunosuppressants and hydroxychloroquine.
T or F
elevated CK levels are common in patients experiencing alcohol withdrawal syndrome and the more severe the withdrawal the higher the CK levels.
T
Cardiac troponin (cTn) is a complex of what three proteins?
troponin C (TnC), troponin I (TnI), and troponin T (TnT)
T or F
Cardiac troponins are normally found in high concentrations in the blood.
F
These proteins are ordinarily found in cardiac muscle, but not normally found in high concentrations in the blood.
T or F
cardiac ischaemia is always caused by myocardial infarction.
F
often but not always
The major use of troponin assays is to either diagnose or exclude what?
acute myocardial infarction.
T or F
Chest pain is a non-specific symptom
T
What am I?
This biomarker is an enzyme that indicates non-specific muscle damage. It can more than double in people who have had a heart attack but can also be elevated due to other conditions that cause muscle damage.
CK
What am I?
This peptide biomarker is not diagnostic for a heart attack. Rather, it is released as the body’s natural response to heart failure, such as stretching of the heart muscle wall. Increased levels of this biomarker indicate an increased risk of cardiac problems in a person experiencing symptoms of chest pain.
BNP and NTproBNP
What am I?
The most useful cardiac biomarker for diagnosing myocardial infarctions (heart attacks), as it is very specific for the heart.. This biomarker is three different types of proteins joined together, which become cleaved when released from heart muscle. These proteins are useful measures of myocardial damage. These biomarkers stay in the bloodstream days after other biomarkers return to normal levels.
Cardiac troponin
What am I?
cardiac specific subtype of a generalised enzyme biomarker for muscle damage. This marker tends to rise 4 to 6 hours after a heart attack but returns to normal after a day or two, which limits its utility.
CK-MBA
T or F
A biomarker alone is enough to diagnose an MI
F
B-type Natriuretic Peptide (BNP) and N-terminal-proBNP (NT-proBNP) belong to a family of protein hormones called ….
natriuretic peptides.
Natriuretic peptides are released when the heart muscle (ventricular wall of the heart) is …
stretched.
Stretching of the ventricular wall of the heart often occurs in patients who are … overloaded and who have reduced ….
fluid
cardiac output.
T or F
BNP reduces the production of adrenaline and testosterone
F
adrenaline and aldosterone
T or F
The actions of BNP on the kidneys leads to the excretion of more potassium
F
salt and water
T or F
BNP acts on blood vessels causing them to dilate
T
Angiotensin promotes … and … retention, vasoconstriction/vasodilation, … outflow, cardiac hypotrophy/hypertrophy and fibrosis.
fluid and sodium
vasoconstriction
sympathetic
hypertrophy
What drug class does valsartan belong to?
Angiotensin II receptor blocker (ARB)
What drug class does sacubitril belong to?
neprilysin inhibitor
Natriuretic peptides are metabolised by the enzyme …
neprilysin.
T or F
Most of the body’s potassium is found intracellularly
T
T or F
Minor changes in serum potassium concentration can have significant consequences.
T
T or F
Both hypokalaemia (low K+) and hyperkalaemia (high K+) are serious conditions but can’t be fatal.
F
They can be fatal
What am I? (hypokalaemia or hyperkalaemia)
I can cause peaked T waves, wider QRS complex (ECG changes) and may result in bradycardia, asystole, and sudden cardiac death?
Hyperkalaemia
What am I? (hypokalaemia or hyperkalaemia)
I can cause significant QT prolongation (ECG changes) with a subsequent risk or torsades des pointes, ventricular fibrillation, and sudden cardiac death.
Hypokalaemia
Why is decreased dietary intake NOT the major cause of hypokalaemia?
the kidney can lower potassium excretion in the presence of potassium depletion, hence decreased intake alone rarely causes significant hypokalaemia.
T or F
Thiazide diuretics cause hypokalaemia more frequently than loop diuretics
T
What two overarching mechanisms can cause a rise in serum potassium (hyperkalaemia)?
- Increased potassium release from cells
- Reduced urinary potassium excretion
Aside from certain medications other factors that may contribute to the risk of a person developing hyperkalaemia include:
Increasing age, metabolic acidosis, poorly controlled diabetes mellitus, increased potassium intake via supplements, dehydration, chronic kidney disease, hyperaldosteronism
What causes hyperkalaemia or pseudohyperkalamia?
where the appearance of hyperkalaemia based on high serum concentrations is due to the movement of potassium out of the cells during or after a drug specimen has been drawn.
The … is the largest and heaviest solid organ of the body
liver
The … contains the body’s largest reservoir of phagocytotic (macrophages) cells.
liver
Vitamin … is absorbed and synthesised through the action of bile salts
K
… is a toxic waste product derived from the breakdown of proteins.
Ammonia
T or F
transaminase levels directly correlate to the degree of liver damage.
F
T or F
Fibrate drugs such as fenofibrate are more effective than Statins in treating hypertriglyceridaemia where lifestyle alone has failed
T
Hypertriglyceridaemia is associated with an increased risk of which diseases?
Coronary heart disease and pancreatitis
What is the difference between primary and secondary prevention of LDL-c?
Primary prevention = patient has not had a previous cardiovascular event.
Secondary prevention = patient has experienced a cardiovascular event, and is thus at a greater risk of a subsequent event.
T or F
cholesterol levels are generally higher in the morning and lower in the evening (when cholesterol synthesis peaks)
F
vice versa
T or F
The effect of statins on lowering LDL cholesterol
levels is linear as the dose is increased.
F
not linear
Which statins would you recommend to be dosed at night?
Fluvastatin, pravastatin and simvastatin
Fibrates are associated with an increased risk of myopathy
and rhabdomyolysis when combined with …
statins.
Which fibrate is most likely to increase the risk of myopathy and rhabdomyolysis, and increase statin serum concentrations when combined with statins?
Gemfibrozil
Which medication am I?
I am an add on treatment in patients who have high cholesterol despite the use of a maximum tolerated statin dose.
Ezetimibe
What is the name of the only bile acid binding resin available in Australia?
Colestyramine
Bile acid binding resins should be taken … hour after taking other medications, or … to … hours before taking other medications.
one
4 to 6
T or F
Fish oil is a coagulant
F
It is an anticoagulant
What is the first-line medication for the treatment of raised LDL-c?
statins
What is the first-line medication for the treatment of severely raised TGs.
fibrates
What parts of the kidney in isolation, are capable of performing all functions of the kidney?
The nephron and collecting ducts
T or F
The heart does not exercise influence on arterioles, but the kidneys do.
T
Which parts of the nephron play a role in tubular reabsorption and secretion?
Loop of Henle, distal convoluted duct, proximal convoluted duct and the collecting duct.
T or F
As the age advances, the number of nephrons decreases.
T
What does micturate mean?
to urinate
Most of the bladder lumen is thrown into folds
and these folds give inside of the bladder a wrinkled appearance.
These folds are known as …
rugae.
Only a small part of the bladder, called the …, is smooth.
trigone
When the bladder fills up, the … will flatten.
rugae
T or F
The body is not capable of measuring blood volume.
T
The body can determine blood pressure through the baroreceptors
in the … and ….
aorta
carotid sinuses.
The body can determine blood pressure through the …
in the aorta and carotid sinuses.
baroreceptors
T or F
Increased pressure leads to widespread vasocontriction.
F
vasodilation
The cardiomyocytes in the atria respond to changes in blood pressure by secreting …
ANP
T or F
When blood passes through the glomerulus,
it produces a filtrate.
This filtrate does not contain protein.
T
Filtrate produced by the glomerulus is is captured by what?
The Bowman’s capsule
(referring to the kidneys)
Where does tubular secretion mostly occur?
in the proximal and distal convoluted tubules
What factors determine the generation of filtrate in the Bowman’s space?
Blood hydrostatic
pressure, blood colloid osmotic pressure, and the capillary hydrostatic pressure
What is nocturia?
A desire to urinate at night-time. The individual might have to wake up 1-2 times to void.
Sodium is reabsorbed in all parts of the nephron except…
the thin descending segment
Why does increasing salt in your diet increase you BP?
sodium results in retention of water, leading to expansion of vascular volume. The larger the volume of blood the higher the pressure it exerts. Think about Frank Starling’s law!
T or F
The total
peripheral resistance helps define the function of the heart, whereas cardiac output helps understand the properties of the vasculature.
F
vice versa
T or F
Hypokalemia is more prevalent than hyperkalemia
T
A significant rise in the extracellular potassium concentration causes a sustained …
depolarisation.
T or F
Unless the kidney is grossly damaged proteins and fat do not appear in the urine
T
