Renal disease

Question 1

how does the kidney regulate the following:

Regulation of blood pressure
Regulation of calcium and bone metabolism
Regulation of haematocrit

Answer 1

Regulation of blood pressure
- Renin

Regulation of calcium and bone metabolism
- 1,25 Dihydroxycholecalciferol

Regulation of haematocrit
- Erythropoietin

Question 2

what is the Basic unit of the kidney?

Answer 2

nephron

Question 3

what creates charge-dependent (anionic) and size-dependent barrier/filter in the glomerulus of the nephron?

Answer 3

podocytes

Question 4

what are the untis in the Nephron and their various roles?

Answer 4

The Proximal Convoluted Tubule

- is always doing the most
- reabsorption n co-transport

Descending loop of henle
- permeable to H20

Ascending loop of henle
- actively resorbs sodium and chloride

DCT
Regulates pH via active transport
Regulates Na K via active transport
Regulates calcium

Collecting Duct
Resorbs water (principal cells, antidiuretic hormone)
Regulates pH (intercalated cells, proton excretion)

Question 5

how would you describe the endothelial cells of the glomerulus?

Answer 5

fenestrated

Question 6

give an example of a condition involving Immune Complex deposition in the Kidney.

what findings would there be?

Answer 6

condition - membranous glomerulonephritis:

IgG would be seen on EM
leads to complement activation so C3 seen too
subendothelial deposits
lack of podocyte foot processes

Primary disease is autoimmune
Antibody against phospholipase A2 type M receptor (PLA2R) in 75% of cases

Question 7

what is the aetiology, presentation and associations of :

Polycystic Kidney Disease

Answer 7

Adults
Autosomal Dominant

Presents in adulthood with hypertension, flank pain and haematuria

PKD1, PKD

Association: Berry aneurysms

Question 8

Cysts on the kidney commonly develop in patients with ___?

Answer 8

end stage renal disease who are on dialysis

Question 9

list some causes of AKI / AK failure

Answer 9

Pre-Renal: Failure of perfusion, dehydration (eg vomiting)

Renal: Acute tubular injury, acute glomerulonephritis, thrombotic microangiopathy

Post-Renal: Obstruction

Question 10

what is the Commonest cause of acute renal failure?

Answer 10

Acute tubular injury

Question 11

what are the causes of Acute tubular injury?

Answer 11

Tubular epithelial cells damaged by:

Ischaemia
Toxins (contrast, haemoglobin, myoglobin, ethylene glycol)
Drugs - NSAIDs

2. Failure of Glomerular Filtration

Question 12

list some causes of Acute Tubulo-Interstitial Nephritis

Answer 12

Immune injury to tubules and interstitium

Due to infection and drugs - DRUGS major cause

Question 13

What are the ivx findings of Acute Tubulo-Interstitial Nephritis?

Answer 13

Heavy interstitial inflammatory infiltrate with tubular injury

Can see eosinophils, granulomas

Question 14

what Presents with oliguria with urine casts containing erythrocytes and leucocytes?

tips: may also have crescents present & Proliferation of cells within Bowman’s space

Answer 14

Acute Glomerulonephritis

Question 15

what iis the aetiology and features of Anti-GBM Disease?

Answer 15

The antibody attacks C-terminal domain of Type IV collagen
antibodies directed against the glomerular basement membrane

Linear deposition of IgG

can cause pulmonary haemorrhage if targets alveolar BM

Question 16

which Immune Complex Associated Glomerulonephritis is Usually ANCA-associated?

Answer 16

Pauci-Immune Crescentic Glomerulonephritis

Question 17

define nephrotic syndrome

Answer 17

Proteinuria (>3.5g/day)
Hypoalbuminemia
Oedema
Hyperlipidaemia

Question 18

list some causes of nephrrotic syndrome

Answer 18

Non-Immune Complex Related:
Minimal Change Disease
Focal Segmental Glomerulosclerosis

Immune Complex Mediated:
Membranous Glomerulonephritis

Systemic Disease:
Diabetes mellitus
Amyloidosis
SLE

Question 19

give some features of Minimal Change Disease

Answer 19

Glomeruli look normal by light microscopy
Effacement of foot processes on electron microscopy

Common cause of nephrotic syndrome in children
Generally responds to immunosuppression

Question 20

how does Diabetic Nephropathy present?

Answer 20

Typically starts as microalbuminuria before progression to proteinuria and nephrotic syndrome

Pattern seen is Nodular Glomerulosclerosis

Question 21

What are the Commonest forms off amyloid in kidneys?

Answer 21

AA, derived from serum amyloid associated protein (SAA), an acute phase protein; patients tend to have a chronic inflammatory state

AL, derived from immunoglobin light chains; 80% of patients have multiple myeloma

Question 22

ivx for amyloid?

Answer 22

Congo red stain – pink in normal light

Polarised light – apple green birefrringence

Question 23

list some causes of a thin Basement Membrane?

how would it present?
name 1 eg condition?

Answer 23

Hereditary defect in Type IV collagen synthesis
Basement membrane <250nm thickness
Haematuria is only consequence in most cases

presentation - microscopic haematuria

Alport’s Syndrome
X-linked dominant mutations affecting ⍺5 subunit
Forms exist in which mutation affects ⍺3 or ⍺4 subunit
Typically progressive, renal failure in middle age
Often have deafness, ocular disease

Question 24

how does IgA Nephropathy present?

Answer 24

microscopic haematuria

Can be seen with small-vessel vasculitis (Henoch-Schönlein Purpura)

30% develop end stage renal failure

Question 25

list the causes of CKD in order with the most common first ?

Answer 25

Diabetes – 27.5%
Glomerulonephritis – 14.1%
Polycystic Kidney Disease – 7.4%
Pyelonephritis – 6.5%
Hypertension – 6.8%

Question 26

on histology, global glomerulosclerosis is noted. what is this indicative of?

Answer 26

Hypertensive Nephropathy

Question 27

which antibodies are present in SLE?

Answer 27

Anti-nuclear and Anti-dsDNA antibodies are typical