Glomerular Disease: Nephritic Syndrome

Question 1

Define nephritis syndrome

Answer 1

Clinical presentation

Symptoms = high bp, mild oedema, urine dip with blood and protein

Question 2

Define glomerulonephritis

Answer 2

Pathological diagnosis made post kidney biopsy

Question 3

Define rapidly progressive GN

Answer 3

GN Patients diagnosed with rapid fall in renal function for the worst

Question 4

Clinical presentation

Answer 4

• red casts on urine microscopy
• proteinuria (may be milder - 1-1.5g/day)
• hypertension, oedema, AKI as disease progresses
• glomerular inflammation

Question 5

Urine dip

Answer 5

• blood and protein
• only a clue
• is positive = send for cytology (red cell casts) and culture (rule out infection)
• send for microscopy commonly but red cell casts often missed

Question 6

Hallmark of glomerulonephritis

Answer 6

• red cell casts

- indicates inflammation in glomerulus

Question 7

Forms of GN

Answer 7

AUTOIMMUNE
- SLE
- vasculitis
- IgA nephropathy
- cryoglobulinemia
INFECTIONS
- hep C, hep B, HIV
- post streptococcal
- subacute bacterial endocarditis
MALIGNANCIES
- lymphoma
- multiple myeloma

Question 8

Mechanism of glomerular inflammation

Answer 8

• immunoglobulin mediated
• = deposition of antibodies (IgA, anti GBM, immunecomplexes)
• = activation of complement
• release of chemokines
• recruitment of leukocytes (neutrophils, macrophages, lymphocytes)
• = further release of chemokines and cytokines
• = inflammation, necrosis, crescent formation

Question 9

Early vs. Late Phases

Answer 9

• no damage, red cell casts on urine microscopy
• then infiltration of more cells
• then formation of crescent and necrosis
• later 3 = hypertension, oedema, renal impairment

Question 10

Investigations

Answer 10

• urine microscopy = red cell casts
• urine PCR 24 hour urine test
• FBC
• clotting
• U&E
• LFTs
• microbiology blood culture
• renal US
• CXR

Question 11

Nephritis Screen (GN SCREEN) investigations to find cause

Answer 11

• complements C3/C4
• anti-streptolysin O titres
• immunoglobulins IgG,M,A
• ANA, anti ds-DNA
• serum electrophoresis
• hepatitis C, hep B, HIV
• ANCA
• GBM antibody
• cryoglobulins

Question 12

What does it mean if on GN screen ANCA are present?

Answer 12

• likely vasculitis
• biopsy will show crescentic necrotising GN
• = ANCA associated vascultis

Question 13

ANCA associated vasculitis

Answer 13

• anti neutrophil cytoplasmic antibodies
• if proteinase 3 (PR3) antigen = cytoplasmic type
• if myeloperoxidase (MPO) antigen = perinuclear type
• disease associations = drug induced, small vessel -> churg-strauss, wegeners (cANCA), microscopic polyangiitis (pANCA)
• false positive ANCA with infections (endocarditis)

Question 14

Common causes of complements apart from GN

Answer 14

• low c3 and c4 with renal disease
• SLE
• mesangiocapillary GN associated with hep C
• cryoglobulinaemia
• positive strep GN
• infective endocarditis
• foreign bodies (shunt nephritis)
• cholesterol emboli