Mixture Flashcards
What is the role of a nephron?
Filtering unit
Which structure is damaged in nephrotic syndrome?
Epithelial foot process
In nephrotic syndrome what 3 problems occur?
Proteinuria
Hypoalbuminaemia
Oedema
How is blood pressure controlled in kidneys?
Renin secretion:
- Salt/water retention
- converts angiotensinogen to angiotensin I
How is urine formed?
Capillary hydrostatic pressure forces water/salts of plasma across to GBM (glomerular basement membrane)
Name 3 factors affecting filtration rate across GBM?
1) molecular weight
2) hudrostatic pressure in afferent arteriole
3) surface charge (GBM = -ve)
Which 3 things should you not find in urine of healthy person?
1) protein
2) glucose
3) amino acids
What is method to adapt urine concentration called?
Where in kidney does this occur?
Counter current mechanism
Medulla
What is the function of proximal convoluted tubule?
Recovers 70% glomerular filtrate
Recovers and generates bicarbonate secretion
What enzyme does acetazolamide inhibit?
What process is dependent on this enzyme?
Carbonic anhydrase
Reabsorption of bicarbonate
What happens at the ascending limb of henle?
Uptake of Na, 2Cl, K, H2O
Where is the site of loop diuretics?
What do they do?
Ascending limb of henle
Reduce Na, K, Cl, H2O
What happens at distal tubule?
Reabsorption of Na with Cl (co-transport mechanism)
Which type of diuretics act in distal tubule?
Thiazide diuretics
What gets reabsorbed in cortical collecting duct?
What controls this?
Na (with H2O and Cl) in exchange for K
Aldosterone
What is spironalactone?
What is the risk with this drug?
Aldosterone antagonist
Hyperkalaemia
Where is the site of urinary concentration?
What hormone acts here to control water reabsorption?
Medullary collecting duct
Anti diuretic hormone (ADH)
How does diabetes insipidus affect ADH?
Failure to secrete ADH
Peripheral resistance to ADH
What is furosemide?
Loop diuretic
What stimulates erythropoietin?
Hypoxia (low O2)
What vitamin is activated by kidneys?
What does it increase absorption of?
Vitamin D
Calcium
What is a secondary problem of decreased vitamin D levels in kidney?
Renal osteodystrophy:
decreased vit D –> decreased Ca –> stimulation of parathyroid hormone –> secondary hyperparathyroidism –> bone disease (renal osteodystrophy)
What is a normal range of kidney function from the following: 50-80mls/min/1.73^2 80-100mls/min/1.73^2 100-120mls/min/1.73^2 120-150mls/min/1.73^2
100-120mls/min/1.73^2
Name two ways to measure kidney function exactly?
1) Inject radioactive tracer - Technetium (Tc^99)
2) Creatinine clearance
What 4 variables are needed to work out eGFR?
1) Age
2) Sex
3) Ethnicity
4) Serum creatinine
What is the difference in time to accquire disease between AKI and CKD?
Can they be recovered?
AKI acquired abruptly
- potential to recover
CKD acquired progressively
- irreversible
What is normal range of pH of blood?
7.35-7.45
What is normal range of PCO2 in arterial blood?
4.5-5.4kPa
What is normal range of HCO3- in blood?
24-30mmol/L
Name 2 intracellular ions?
Potassium
Phosphate
Name 2 extracellular ions?
Sodium
Chloride
What is aldosterone responsible for in electrolyte homestasis?
Reabsorbing Na in exchange for K
What hormone controls calcium?
Parathyroid hormone
What does calcitonin do to calcium?
Enhances renal excretion of Ca so lowers levels
Name 2 risks of hypervolaemia?
1) High BP
2) Oedema
Name a risk of hypovolaemia?
Low BP
What does atrial natriutertic peptide do to renin?
What is its effect on Na excretion?
Inhibits it
Reduces Na excretion into urine
What secretes antiduiretic hormone (ADH)?
Name something that blocks the action of ADH?
Pituitary
Alcohol
Here are 3 types of hameaturia: Dipstick haematuria Microscopic haematuria Macroscopic haematuria How can they be confirmed?
Dipstick haematuria - +ve urinalysis
Microscopic haematuria - RBCs on microscopy
Macroscopic haematuria - blood visible in urine
Which 2 genes are responsible for Autosomal-dominant polycystic kidney disease (ADPKD)?
PKD1 (XX/Y 16) - polycystin 1
PKD2 (XX/Y 4) - Ca ion channel
Advantages of peritoneal dialysis
Increased flexibility
Better mobility
Less fluid restriction
No anti-coagulation
Advantages of haemodialysis
Less responsibility
Shorter treatment times
Small solute clearance is highly efficient
Disadvantages of
peritoneal dialysis
Large responsibility Storage of equipment Hyperglycaemia Protein losses Complications - hernias, peritonitis
Disadvantages of haemodialysis
Circulatory stress
Scheduled treatment
Risk of bleeding
Complications - infection, hypotension
What do Angiotensin AT1 Receptor Blockers (ARBs) treat?
How?
Hypertension
Prevent angiotensin II working
If the site of immunoglobulin deposition is subendothelial what syndrome results?
Nephritic syndrome
If the site of immunoglobulin deposition is subepithelial deposition what syndrome results?
Nephrotic syndrome
4 symptoms of nephritic syndrome?
1) Haematuria
2) Proteinuria
3) High BP
4) Impaired renal function
