Generalised swelling

Question 1

List the complications of nephrotic and nephritic syndrome.

Answer 1

NEPHROTIC

• Hypovolaemia
• Ascites
• Pleural effusions
• Peritonitis

NEPHRITIC

• Acute renal failure
• Pulmonary oedema due to heart failure
• Hypertensive encephalopathy

Question 2

What are the 5 main causes of generalised swelling?

Answer 2

1. Nephritis
2. Nephrosis
3. Allergic reactionsincluding urticara, angioedema etc
4. Cardiac failure
5. Malnutrition
6. Other causes of hypoalbuminaemia

Question 3

Causes of haematuria in children?

Answer 3

• Post strep GN
• Polycystic kidneys
• Renal stone
• Renal tumour
• Sickle cell disease
• Renal trauma
• UTI
• Orthostatic proteinuria - after exercising/standing
• Acute renal failure
• Nephrotic syndrome

Question 4

Signs of nephrotic vs nephritic syndrome?

Answer 4

NEPHROTIC

• Proteinuria
• Oedema
• Hypoalbuminaemia
• Hyperlipidaemia

NEPHRITIC

• Haematuria
• Oedema
• Hypertension

Question 5

What is IgA nephropathy?

Answer 5

• Berger’s disease
• most common form of nephropathy worldwide
  
  • abnormal IgA forms
  • IgG targets IgA, creating immune complexes
  • immune complexes travel through the blood
  • IgA-IgG immune complexes deposit in the mesangium = activation of the alternate complement pathway = release of proinflammatory cytokines + macrophages into the kidney
  • = glomerular injury = haematuria
• typically seen in childhood - microscopic or gross haematuria
• develops during infection of mucosal lining eg. GIT or resp infections

Question 6

What is PSGN?

Answer 6

Post strep glomerulonephritis

• IgG/IgM antibodies attack group A beta-haemolytic strep = immune complexes form
• deposits end up in the glomerular basement membrane (GBM)
• inflammatory reaction in the glomerulus
  
  • C3 complement
  • cytokines
  • oxidants
  • proteases
  • = damage to the podocytes
  • = RBCs + proteins are able to filter through
• cola urine, oliguria, proteinuria, peripheral + periorbital oedema
• typically affects children
  
  • 6 weeks after skin infection (impetigo)
  • 1-2 weeks after throat infection (pharyngitis)

Question 7

What is rapidly progressive glomerulonephritis?

Answer 7

crescentic glomerulonephritis

• not a seperate disease - any GN may result in RPGN
• leads to renal failure within weeks-months
• some cases are idiopathic
• type 1 - antiglomerular membrane antibodies (anti-GBM), Goodpasture syndrome
• type 2 - caused by immune complex, eg. PSGN, SLE, IgA nephropathy, henoch-scholein purpura
• type 3 - pauli-immune; no anti-GBM or immune complexes
• proliferation of epithelial cells into a thick crescent moon shape, can undergo sclerosis/scarring
• low GFR, can quickly lead to acute renal failure

Question 8

What is MPGN?

Answer 8

Membranoproliferative glomerulonephritis

• presents as nephrotic syndrome, occasionally nephritic
• type 1 - most common
  
  • 1) circulating immune complexes - due to chronic infection (eg. Hep B)
  • immune complexes travel to glomerulus
  • activation of complement pathway
  • 2) inappropriate activation of the complement pathway = no immune complexes
• thickening of basement membrane, proliferation of mesangial cells
  
  • type 2 - only involves complement deposit
  • IgG auto-antibody - nephritic factor

Question 9

What is membranous glomerulonephropathy?

Answer 9

aka. wire loop nephropathy
* nephrotic syndrome

PRIMARY
Auto-Ab to podocyte Ag (Phospholipase A2)
SECONDARY (more common)
▪ Infections = HBV, Malaria
▪ Autoimmune = SLE
▪ Drugs = NSAIDs, captopril
▪ Inorganic Salts = Gold, Mercury,

Pathogenesis:
→ Ab against podocyte Ag (or planted Ag)
→ Subepithelial Ig deposits
→ Directly activates Complement (C5b-C9 + MAC).
→ Only proteinuria, no inflammation