CP31 - Renal System 1

Question 1

what are some of the function of kidney?

Answer 1

• eliminating metabolic waste products
• regulating fluid and electrolyte balance
• influencing acid-base balance (Renin - fluid balance, erythropoietin - stimulate RBC production)

Question 2

what are some symptoms for acute renal failure?

Answer 2

rapid rise in creatinine and urea, generally unwell

Question 3

what are some symptoms for nephrotic syndrome

Answer 3

oedema, proteinuria (mostly albumin), hypoalbuminaemia

Question 4

what are some symptoms for acute nephritis (nephritic syndrome )

Answer 4

oedema, proteinuria, haematuria, renal failure

Question 5

what is the course of blood through the renal system and back to central circulation?

Answer 5

branches of renal artery - afferent arteriole (going towards glomerulus) - glomerulus in bowmans capsule - efferent arteriole - proximal convoluted tubule (going towards renal medulla) - enter vasa recta - back in cortex in distal convoluted tubule - collecting duct - renal vein

Question 6

what is glomerulus

Answer 6

capillary bed - network of blood capillary

Question 7

what are the 2 main mechanisms for glomerular damage?

Answer 7

damage to base membrane & damage to vessels through immunological and non-immunological causes

DM - altered BM as hyperglycaemia

Inherited disease - abnormal BM

deposition of protein

immune complexes, antigen, antibodies deposit in glomerulus

Question 8

what are some of the mechanism for tubular damage?

Answer 8

2 main mechanisms - toxic and ischaemic

direct toxin
hypersensitivity reactions to drugs
deposition of crystals and abnormal proteins in tubules

reduced blood supply to tubules

glomerular damages

Question 9

what can cause vascular damage in the kidney

Answer 9

hypertension
DM
atheroma 
thrombotic mircoangiopathy  - thrombi in capillary and small arterioles 
vasculitis - inflammation of the vessels

Question 10

what causes nephrotic syndrome?

Answer 10

always due to damages to glomerulus

Question 11

what are some examples which cause nephrotic syndrome?

Answer 11

membranous nephropathy (most common)

focal segmenetal glomerulosclerosis (FSGS) -

minimal change disease

DM, lupus nephritis, amyloid

Question 12

what causes nephrotic syndrome in children?

Answer 12

minimal change disease (most common)

focal segemental glomerulosclerosis

Question 13

what are some common causes for acute nephritis (nephritic syndrome) in adult?

Answer 13

post-infective glomerulonephritis - occur a few weeks after Streptococcal throat infection

IgA nephropathy
Vasculitis
Lupus

Question 14

what are some common causes for acute nephritis (nephritic syndrome) in children?

Answer 14

Post-infective glomerulonephritis
IgA nephropathy
Henoch-Schonlein purpura - specific type iGA nephropathy
- haemolytic-uraemic syndrome - E.Coli 0157

Question 15

what are some of the clinical presentation for acute renal failure?

Answer 15

diagnosis - anuria/oliguria + raised creatinine and urea

Question 16

what are the 3 main causes of acute renal failure?

Answer 16

pre-renal - reduced blood flow to kidney (most common) - severe d

renal - damage to the renal tissue

post-renal - obstructed urinary tract

Question 17

what will the biopsy of acute renal failure show?

Answer 17

ATN - acute tubular necrosis/ ATI/ATD/AKI

Question 18

what are some of the most common causes for acute renal failure in adult?

Answer 18

vasculitis

acute interstitial nephritis (tubular damage with inflammation, most commonly caused by drug reactions)

Question 19

what are some of the most common causes for acute renal failure in children?

Answer 19

Henoch-Schonlein purpura
Haemolytic uraemic syndrome
Acute interstitial nephritis

Question 20

what are some of the complications fro acute renal failure?

Answer 20

Cardiac failure (fluid overload)
Arrythmias (electrolyte imbalance)
GI bleeding
Jaundice (hepatic venous congestion)
Infection, especially lung and urinary tract

Question 21

what is chronic renal failure?

Answer 21

premanently reduced GFR - reduced number of nephrons

Question 22

what are the different staging of chronic renal failure

Answer 22

Stage 1: Kidney damage with normal or increased GFR (>90 mL/min/1.73 m2)

Stage 2: Mild reduction in GFR (60-89 mL/min/1.73 m2)

Stage 3: Moderate reduction in GFR (30-59 mL/min/1.73 m2)

Stage 4: Severe reduction in GFR (15-29 mL/min/1.73 m2)

Stage 5: Kidney failure (GFR

Question 23

what are some of the causes for chronic renal failure in adults/

Answer 23

Diabetes (commonest)

Glomerulonephritis

Reflux nephropathy -
Chronic reflux of urine up the ureter leading to repeated infections and scarring of the kidney

Question 24

what are some of the causes for chronic renal failure in children

Answer 24

Developmental abnormalities/malformations
Reflux nephropathy
Glomerulonephritis

Question 25

what can chronic renal failure do?

Answer 25

Reduced excretion of water and electrolytes: oedema, hypertension Reduced excretion of toxic metabolites Reduced production of erythropoietin: anaemia Renal bone disease

Question 26

what are the likely cause of Haematuria +/- proteinuria with normal renal function

Answer 26

likely renal causes - IgA nephropathy Thin basement membrane disease (inherited) Alport type hereditary nephropathy

Question 27

what are some likely causes for isolated proteinuria

Answer 27

May be benign e.g. Postural, related to pyrexia or exercise. May be due to renal disease Adults FSGS Diabetes Lupus Children Henoch-Schonlein purpura FSGS

Question 28

what is pyelonephritis?

Answer 28

infection of the kidney

Question 29

what are the 2 main of pyelonephritis?

Answer 29

acute and chronic

Question 30

what can cause acute pyelonephritis?

Answer 30

- more common in women - instrumentation of urinary tract - DM - structural abnormalities of urinary tract

Question 31

what is the complication for acute pyelonephritis?

Answer 31

abscess forming in the kidney

Question 32

what can cause chronic pyelonephritis

Answer 32

most associated with obstruction of urinary tract and reflux of urine up ureter, leads to scarring of the kidney and can lead to renal failure

Question 33

what are some complication for chronic pyelonephritis?

Answer 33

scarring of kidney, chronic renal failure

Question 34

what are the 2 routes which can transmit.

Answer 34

haematogenous spread, ascending route from bladder

Question 35

what can cause renal artery stenosis

Answer 35

atheroma/arterial dysplasia - leads to ischaemia of the kidney, activation of renin-angiotensin-aldosteron system lead to hypertension - reducced renal function as loss of kidney

Question 36

how can vasculitis affect the kidney?

Answer 36

Inflammation can affect the glomerular vessels and lead to clotting with obliteration of capillary lumens and destruction of the glomerulus Inflammation of larger arterioles within the kidney can lead to hypoxia of the tubules

Question 37

how can hypertension affect the kidney?

Answer 37

Hypertension damages renal vessels leading to thickening of the vessel wall and reduction in size of the lumen This produces chronic hypoxia which leads to loss of renal tubules and reduced renal function Reduced blood flow in the kidney leads to activation of the renin-angiotensin-aldosterone system which exacerbates hypertension

Question 38

how can diabetes affect the kidney?

Answer 38

Hyperglycaemia is the main cause of diabetic nephropathy by damaging the basement membrane Basement membrane becomes thicker and the glomerulus produces excess extracellular matrix which forms nodules Diabetes also damages small vessels leading to ischaemia and damage to renal tubules

Question 39

how can myeloma affect the kidney?

Answer 39

Tumour of plasma cells producing immunoglobulins Excess immunoglobulins deposit in kidney tubules Tubules become damaged Inflammation and fibrosis of kidney occurs Loss of renal tubules leads to declining kidney function