Diseases of the urinary tract 1 (Kidneys and Urinary Tract Pathology) Flashcards
What is the function of the Kidney?
- eliminate waste products
- regulate fluid-electrolyte balance.
- acid-base balance
- produce hormones e.g. Renin and Erythropoietin
What hormones does the kidney produce?
Renin (fluid balance)
Erythropoietin (RBC production)
How many people develop acute / chronic renal disease in the UK per year?
26,000 = acute RD 5,500 = Chronic RD
How do patients with acute renal disease present
1) Acute renal failure:
- rapid rise in CREATININE and UREA.
- generally unwell
How do patients with nephrotic syndrome present?
Nephrotic Syndrome:
- Oedema
- Proteinuria (mostly albumin)
- Hypoalbuminaemia
How do patients with acute nephritis (nephritic syndrome) present?
Acute Nephritis / Nephritic syndrome :
1) Oedema
2) Proteinuria
3) Haematuria
4) Renal Failure
How can immulogical processes cause damage to the glomerular basement membrane?
1) Circulating immune complexes and antigens deposit in glomerulus.
2) Antibodies bind to basement membrane / glomerulus.
3) COMPLEMENT activation, NEUTROPHIL activation, CLOTTING factors then DAMAGE Glomerulus.
What non-immunological processes can cause damage to the glomerulus?
1) Injury to endothelium of vessel.
2) Hyperglucaemia in diabetes can damage basement membrane
3) Genetics can give rise to abnormalities
4) Deposition of abnormal proteins
What are the Ischaemic mechanisms of tubular damage?
ISCHAEMIC:
1) Hypotension,
2) Damage to vessels within kidney
3) Glomerular damage
Can all REDUCE BLOOD supply to tubules causing damage.
What are the toxic mechanisms of tubular damage?
1) direct toxins
2) Hypersensitivity reactions (e.g. to drugs)
3) deposition of crystals in tubules
4) Deposition of abnormal proteins in the tubules.
Can all cause direct tubular damage
What is the effect of thrombotic microangiopathy on the vasculature of the kidney?
1) Thrombi in capillaries and small arterioles
2) occur due to endothelial damage
cause vascular damage
e.g. Haemolytic uraemic syndrome
How does vasculitis cause vascular damage in the kidneys?
- Inflammation of the blood vessel walls,
- obliteration of lumen by inflammation.
e.g. Wegener’s granulomatosis
What are the key features of Nephrotic Syndrome?
- Always due to damaged glomerulus.
- Oedema + Proteinuria (>3g in 24hrs) + Hypoalbuminaemia
What are the common causes of acute nephritis?
- IgA Nephropathy
- Vasculitis
- Lupus
- Haemolytic-uraemic syndrome (children)
What is Haemolytic Uraemic Syndrome?
1) ACUTE NEPHRITIS +
2) HAEMOLYSIS (rupture of RBCs) +
3) THROMBOCYTOPAENIA (decrease platelets)
What are the causes of Acute Renal Failure?
Pre-Renal : Reduced blood flow to the kidney caused by:
- dehyrdration
- hypotension
Renal : Damage to kidney caused by:
- Vasculitis
- Nephritis
Post Renal: Obstructed urinary tact caused by:
- tumour
- stones
- prostatic enlargement
What are the consequences of renal failure?
- cardiac failure (fluid overload)
- Arrythmias (electrolyte imbalance)
- Jaundice (hepatic venous congestion)
What are the characteristics of chronic renal failure?
-Permanently reduced GFR due to the reduced number of nephrons.
What are the common causes of chronic renal failure?
- Diabetes
- Glomerulonephritis
- Reflux nephropathy (reflux of urine causing infection and scarring of kidney)
What are the effects / consequences of Chronic renal failure?
1) Reduced excretion of water and electrolytes leads to OEDEMA and HYPERTENSION.
2) Reduced excretion of toxins
3) Reduced production of erythropoietin leads to ANAEMIA.
4) RENAL BONE disease.
What is isolated haematuria?
Haematuria (with or without proteinuria) with Normal renal function.
What are the causes of isolated haematuria?
- IgA Nephropathy
- thin basement membrane (genetic)
- hereditary nephropathy.
What is Isolated proteinuria?
Proteinuria (less than nephrotic range, so less than 3g in 24hrs)
No renal failure, haematuria or oedema.
What is Pyelonephritis?
Pyelonephritis is infection of the kidney caused by haematogenous spread of infection or via the ureter.
What are the features of acute pyelonephritis?
Acute pyelonephritis:
- usually spreads from urinary tract.
- usually diabetics
- can from abscesses
- more common in women
What are the features of chronic pyelonephritis?
- associated with relfux of urine into kidney leading to infection and scarring.
- chronic renal failure can occur
Describe the causes and features of renal artery stenosis?
Atheroma causes ischaemia of kidney.
Causing reduced renal function.
Describe the association between vasculitis and the kidney.
1) Vasculitis is inflammation of blood vessels.
2) it can cause obliteration of the glomerular vessel lumens thereby destroying the glomerulus.
3) can cause hypoxia of the tubules.
4) can cause rashes and muscle pain
Describe the association between hypertension and the kidney
1) Hypertension damages renal vessels and causes thickening of the vessel wall and reduction of the lumen.
2) leads to HYPOXIA and LOSS of TUBULES»_space;»loss of renal function.
3) Reduced blood flow in the kidney activates RAAS»_space;> increased hypertension.
Describe the association between diabetes and the kidney
1) Hyperglycaemia damages the basement membrane of glomerulus.
2) BM becomes thicker and nodules form.
3) reduced renal function
describe the association between myeloma and the kidney
1) Myeloma is tumour of plasma cells producing immunoglobulins.
2) excess immunoGs deposit in the tubules.
3) tubules get damaged & inflammed.
4) fibrosis of kidney
5) loss of tubules»_space;>loss of renal function.
What causes injury to the endothelium of vessels?
1) Vasculitis
2) Hypertension
3) Clotting
4) diabetes
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