CP31 - Renal System 1 Flashcards
what are some of the function of kidney?
- eliminating metabolic waste products
- regulating fluid and electrolyte balance
- influencing acid-base balance (Renin - fluid balance, erythropoietin - stimulate RBC production)
what are some symptoms for acute renal failure?
rapid rise in creatinine and urea, generally unwell
what are some symptoms for nephrotic syndrome
oedema, proteinuria (mostly albumin), hypoalbuminaemia
what are some symptoms for acute nephritis (nephritic syndrome )
oedema, proteinuria, haematuria, renal failure
what is the course of blood through the renal system and back to central circulation?
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
what is glomerulus
capillary bed - network of blood capillary
what are the 2 main mechanisms for glomerular damage?
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
what are some of the mechanism for tubular damage?
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
what can cause vascular damage in the kidney
hypertension DM atheroma thrombotic mircoangiopathy - thrombi in capillary and small arterioles vasculitis - inflammation of the vessels
what causes nephrotic syndrome?
always due to damages to glomerulus
what are some examples which cause nephrotic syndrome?
membranous nephropathy (most common)
focal segmenetal glomerulosclerosis (FSGS) -
minimal change disease
DM, lupus nephritis, amyloid
what causes nephrotic syndrome in children?
minimal change disease (most common)
focal segemental glomerulosclerosis
what are some common causes for acute nephritis (nephritic syndrome) in adult?
post-infective glomerulonephritis - occur a few weeks after Streptococcal throat infection
IgA nephropathy
Vasculitis
Lupus
what are some common causes for acute nephritis (nephritic syndrome) in children?
Post-infective glomerulonephritis
IgA nephropathy
Henoch-Schonlein purpura - specific type iGA nephropathy
- haemolytic-uraemic syndrome - E.Coli 0157
what are some of the clinical presentation for acute renal failure?
diagnosis - anuria/oliguria + raised creatinine and urea
what are the 3 main causes of acute renal failure?
pre-renal - reduced blood flow to kidney (most common) - severe d
renal - damage to the renal tissue
post-renal - obstructed urinary tract
what will the biopsy of acute renal failure show?
ATN - acute tubular necrosis/ ATI/ATD/AKI
what are some of the most common causes for acute renal failure in adult?
vasculitis
acute interstitial nephritis (tubular damage with inflammation, most commonly caused by drug reactions)
what are some of the most common causes for acute renal failure in children?
Henoch-Schonlein purpura
Haemolytic uraemic syndrome
Acute interstitial nephritis
what are some of the complications fro acute renal failure?
Cardiac failure (fluid overload) Arrythmias (electrolyte imbalance) GI bleeding Jaundice (hepatic venous congestion) Infection, especially lung and urinary tract
what is chronic renal failure?
premanently reduced GFR - reduced number of nephrons
what are the different staging of chronic renal failure
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
what are some of the causes for chronic renal failure in adults/
Diabetes (commonest)
Glomerulonephritis
Reflux nephropathy -
Chronic reflux of urine up the ureter leading to repeated infections and scarring of the kidney
what are some of the causes for chronic renal failure in children
Developmental abnormalities/malformations
Reflux nephropathy
Glomerulonephritis
what can chronic renal failure do?
Reduced excretion of water and electrolytes: oedema, hypertension
Reduced excretion of toxic metabolites
Reduced production of erythropoietin: anaemia
Renal bone disease
what are the likely cause of Haematuria +/- proteinuria with normal renal function
likely renal causes -
IgA nephropathy
Thin basement membrane disease (inherited)
Alport type hereditary nephropathy
what are some likely causes for isolated proteinuria
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
what is pyelonephritis?
infection of the kidney
what are the 2 main of pyelonephritis?
acute and chronic
what can cause acute pyelonephritis?
- more common in women
- instrumentation of urinary tract
- DM
- structural abnormalities of urinary tract
what is the complication for acute pyelonephritis?
abscess forming in the kidney
what can cause chronic pyelonephritis
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
what are some complication for chronic pyelonephritis?
scarring of kidney, chronic renal failure
what are the 2 routes which can transmit.
haematogenous spread, ascending route from bladder
what can cause renal artery stenosis
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
how can vasculitis affect the kidney?
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
how can hypertension affect the kidney?
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
how can diabetes affect the kidney?
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
how can myeloma affect the kidney?
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
