Week 9 Renal system 1 Flashcards Preview

Year 2 clinical pathology > Week 9 Renal system 1 > Flashcards

Flashcards in Week 9 Renal system 1 Deck (80)
1

What is the functions of the kidney?

Eliminating metabolic waste products

Regulating fluid and electrolyte balance

Influencing acid-base balance

Production of some hormones

2

What hormones are produced by the kidney?

Renin: fluid balance

Erythropoietin: stimulates red cell production

3

What are the different presentations of renal disease?

Acute renal failure

Nephrotic syndrome

Acute nephritis (nephritic syndrome)

Chronic renal failure

Haematuria

Proteinuria

4

What are the 5 ways of diagnosing a patient?

Renal physician
Radiologist
Biochemist
Urologist
Pathologist

5

Where are the glomerulus in the kidney found?

Glomerulus are coiled capillary that are found in the bowmans space

6

What structures in the kidney allow filteration of the blood?

Podocyte foot processes, endothelial cells and basement membrane allow filtration

7

What are the immunological mechanisms of glomerular damage?

Circulating immune complexes deposit in glomerulus

Circulating antigens deposit in glomerulus

AutoAntibodies to basement membrane or other components of glomerulus

8

What is the consequence of immunoligical mechanisms that cause glomerular damage.

Lead to Complement activation
Neutrophil activation
Reactive oxygen species
Clotting factors

9

What are the non-immunological mechanisms of damaging glomerur?

Injury to endothelium of vessels e.g. hypertension
Altered basement membrane due to hyperglycaemia in diabetes

Abnormal basement membrane or podocytes due to inherited disease

Deposition of abnormal proteins in the kidney e.g. amyloid

10

What are the ischaemic mechanisms for causing tubular damage?

Hypotension --> septic shock can cause this

Damage to vessels within kidney

Glomerular damage

11

Why does glomerular damage cause damage to the tubular?

If anything damage the glomerular will damage the tubule because disruption to blood supply in the glomerular will reduce blood supply to the tubule and get necrosis and death

12

What are the toxic mechanisms of tubular damage?

Direct toxins
Hypersensitivity reactions e.g. to drugs

Deposition of crystals in tubules

Deposition of abnormal proteins in the tubules

13

What does damage to renal tubules correlate with?

The degree of damage to renal tubules correlates well with renal function
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14

What are the mechanisms of vascular damage of the kidney?

Thrombotic microangiopathy

Vasculitis

Hypertension

Diabetes

Atheroma e.g. Renal artery stenosis

15

How does vasculitis cause vascular damage to the kidney?

Most common cause

Acute or chronic inflammation of blood vessel walls
obliteration of lumen by inflammation
various different types affecting different sizes of vessel
adults and children can be affected
e.g. Wegener’s granulomato

16

What is the thrombotic microangiopathy mechanism for vascular damage?

Not very common

Thrombi in capillaries and small arterioles
Due to damage endothelium
Causes of endothelial damage include bacterial toxins, some drugs, abnormalities in complement or clotting systems
e.g. Haemolytic uraemic syndrome

17

How do you name glomerular disease?

Glomerular disease name can be based on the actual disease that has a idiopathic cause sometimes

Or can be based on the appearance (when secondary to a known cause)

18

What is the cause of nephrotic syndrome?

Always due to damage to glomerulus

19

What is the consequence of nephrotic syndrome?

Oedema --> can be chronic
Proteinuria (>3g in 24h)
Hypoalbuminaemia
+/- hypertension
+/- hyperlipidaemia

20

What are the complications of nephrotic syndrome?

Infection
Thrombosis

21

What are the common causes of nephrotic syndrome in adults seen on renal biopsy?

Membranous nephropathy (most common)


Focal segmental glomerulosclerosis (FSGS)


Minimal change disease


Other causes: diabetes, lupus nephritis, amyloid

22

What is the profile of membranous nephropathy?

Idiopathic
Primary glomerular disorder of unknown cause
Usually adults 30-60, M>F
20-30% progress to end stage renal failure

23

What is focal segmental glomerulosclerosis?

A pattern of kidney damage with various possible causes (idiopathic, genetic, heroin use, HIV. Most are idiopathic)
M>F

24

In minimal change disease is the biopsy abnormal and in which gender is it more common in?

Biopsy is normal on light microscopy
M=F

25

What is the common cause of nephrotic syndrome in children seen on renal biopsy?

Minimal change disease (most common)
No abnormality seen on light microscopy
Majority of children have excellent prognosis

Focal segmental glomerulosclerosis (FSGS)
rare

Other causes are rare

26

What are the presentations of acute nephritis?

Oedema
Haematuria
Proteinuria
Hypertension
Acute renal failure

27

What are the common causes of acute nephritis?

Post-infective glomerulonephritis
IgA nephropathy
Vasculitis
Lupus
Other forms of primary glomerulonephritis

28

How does post infective glomerulonephritis occur?

Typically occurs a few weeks after Streptococcal throat infection
The antibodies against strept cross react with the kidney and cause renal failure
Most recover completely

29

How common is IgA nephropathy?

Most common primary glomerular disease worldwide
Teenagers and young adults with haematuria
20-50% progress to renal failure over 20 years

30

How does vasculitis cause acute nephritis and what is its presentation?

Inflammation to the blood vessel that damage the glomerulus

Presentation--> Fever, generally unwell, may have rash, myalgia, arthralgia

31

In who do you see lupus causing acute nephritis?

Young women

32

What are the common cause of acute nephritis in children?

Post-infective glomerulonephritis
IgA nephropathy
Henoch-Schonlein purpura

33

What is Henoch-Schonlein purpura?

Specific type of IgA nephropathy, M>F

Typically young boys/teenagers with arthralgia, abdo pain, rash, haematuria, acute renal failure

Most recover completely

34

What is haemolytic uraemic syndrome?

Typically children with E. Coli 0157 enteritis
Acute nephritis + haemolysis + thrombocytopaenia

35

What is the diagnosis and prognosis of acute renal failure?

Diagnosis – anuria/oliguria + raised creatinine and urea

Many patients will recover and have good renal function if they had healthy kidneys previously

Short term dialysis may be needed in some patients

36

What are the caues of acute renal failure?

Pre-renal: reduced blood flow to kidney
Severe dehydration
Hypotension e.g. Bleeding, septic shock, left ventricular failure

Post-renal: obstructed urinary tract
Tumours of urinary tract
Tumours in pelvis
Bladder stones
Prostatic enlargement

Renal: damage to kidney

37

When is biopsy helpful to identify acute renal failure?

When the cause is damage to the kidney

Not useful in pre or post renal causes

38

What do all biopsies show in acute renal failure?

All biopsies will show “ATN” – acute tubular necrosis/ injury/damage/acute kidney injury (ATI/ATD/AKI)

39

What is the main cause of acute renal failure in adults?

Vasculitis --> rash fever, muscle pain

Acute interstitial nephritis/tubulointerstitial nephritis (tubular damage with inflammation, most commonly caused by drug reactions)

40

What is the common cause of renal failure in children?

Henoch-Schonlein purpura
Haemolytic uraemic syndrome
Acute interstitial nephritis

41

What is the most common cause of acute renal failure?

Pre renal --> reduced blood flow to kidney

42

What are the complications of acute renal failure?

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

43

What is the treatment of acute renal failure?

Short term dialysis may be needed
Treat the underlying cause

44

Define chronic renal failure?

Permanently reduced GFR – reduced number of nephrons

45

What are the 5 stages 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

46

What is the common cause of chronic renal failure in adults?

Diabetes (commonest)
Glomerulonephritis
Reflux nephropathy

47

What is reflux nephropathy?

Chronic reflux of urine up the ureter leading to repeated infections and scarring of the kidney
Commonly for younger patients

48

At what stage of chronic renal failure do you need treatment?

Stage 4 and 5

49

If you are on dialysis what stage are you at?

Automatically stage 5

50

What are the common causes of chronic renal failure in children?

Developmental abnormalities/malformations
Reflux nephropathy
Glomerulonephritis

51

Why is renal biopsy not helpful in establishing chronic renal failure?

Kidney shows severe scarring with loss of glomeruli and tubules

Similar changes are seen in end-stage renal disease due to any cause

52

What are the effects of chronic renal failure? (4)

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

53

What is the common cause if a elderly patient has acute renal failure?

Acute interstitial nephritis due to drug reactions

Myeloma --> tumor of plasma cells which will release large amount of immunoglobins that accumulate in the glomeruls and tubules that cause damage to the kidneys

54

What is the diagnosis if a young male has haematuria and rash?

Henoch-Schonlein purpura

55

What is the possible diagnosis if a teenager/young adult has haematuria?

Post-infective glomerulonephritis
IgA nephropathy

56

What is the likely cause if a adult has renal failure, fever and mylgia?

Vasculitis?

57

What is the diagnosis if a young women has haematuria and facial rash?

Lupus

58

What is the diagnosis if a adult has nephrotic syndrome?

Membranous nephropathy
Mostly idiopathic

59

What is the likely diagnosis if a child has nephrotic syndrome?

Minimal change disease

60

What investigations are needed to identify the cause of isolated haematuria?

Cystoscopy and other urological investigations are likely to be needed

61

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

IgA nephropathy
Thin basement membrane disease
Alport type hereditary nephropathy

62

What is thin basement membrane disease?

Inherited condition causing abnormally thin basement membranes in the glomerulus
If no other renal disease present, kidney function will remain normal

63

What is Alport type hereditary nephropathy?

Inherited abnormalities of collagen type IV cause abnormal basement membrane in the glomerulus, sometimes with eye and ear problems

Renal failure +/- deafness +/- ocular problems

May be autosomal or X-linked

64

What is isolated proteinuria?

Proteinuria less than the nephrotic range, without haematuria, renal failure or oedema

65

What are the causes of isolated proteinuria in adults?

FSGS
Diabetes
Lupus

66

What is the common cause of isolated proteinuria in children?

Henoch-Schonlein purpura
FSGS

67

What is a complication of acute pyelonephritis ?

Abscess formation

68

What is Pyelonephritis ?

Infection of the kidney

69

What is the action of acute pyelonephritis?

Instrumentation of urinary tract

Structural abnormalities of urinary tract

70

In who is acute pyelnophritis common in?

Diabetics
More common in women (ascending infection)

71

What are the two routes of pyelonephritis?

Infection can occur via haematogenous spread

Infection via ascending route from bladder

72

What is chronic pyelonephritis associated with?

most associated with obstruction of urinary tract and reflux of urine up ureter

73

What can chronic pyelonephritis lead to?

Leads to scarring of the kidney and can lead to renal failure

74

What are the complications of chronic pyelonephritis?

Scarring of kidney
-Chronic renal failure

75

What is the cause of renal artery stenosis?

Due to atheroma (most common) or arterial dysplasia

76

What does renal artery stenosis lead to?

Leads to ischaemia of the affected kidney

Activation of renin-angiotensin-aldosterone system leads to hypertension

Loss of renal tissue due to ischaemia leads to reduced renal function

77

How does vasculitis affect the kidney?

Vasculitis is inflammation of blood vessels

Various types occur and affect different sizes of vessels

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

Often affects other vessels around the body causing rash, muscle and joint pains

Patients can also have fever and weight loss due to the inflammation

78

How does hypertesion 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

79

How does diabetes affect the kidney?

Diabetes is the commonest cause of end-stage renal failure in Europe and the USA

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

80

How does 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
Renal impairment due to myeloma is usually irreversible