Glomerulonephritis (2) Flashcards
Supportive treatment of glomerulonephritis
Supportive:
- lifestyle modification
- salt and water restriction
- control BP
- nutrition -> not to give too much potassium/phosphate (as it comes out mostly in urine, so if oliguria then potassium build up)
- prevention of thromboembolism -> risk of clots increase when low plasma protein (as anticoagulants are proteins - lost with proteinuria)
- treat infections
- electrolytes and acid balance
- renal replacement therapy
Definitive treatment of glomerulonephritis
Definitive treatment - to treat the underlying cause of glomerulonephritis
- treat the underlying cause -> infection, cancer etc.
- immunosuppression -> steroids, alkylating agents etc.
- plasmapheresis -> plasma and abnormal antibodies in it are replaces
- renal transplant -> if all the other treatment fails and kidney cannot be saved
Answer:
C. IgA vasculitis (HSP)
This is because it happens 2 days after the sore throat (post-strep would happen 2-3 weeks post infection)
Henoch Schonlein Purpura: presents with abdominal pain, and blood in the urine, rash
Other investigations: biopsy to confirm diagnosis and how bad it has become
Henoch-Schonlein Purpura
- another name
- how common is it
- population profile
Henoch- Schonlein Purpura
- aka IgA nephropathy
- the commonest cause of primary glomerulonephritis
- 20-30 years old / children following an infection
Henoch Schonlein Purpura
- what happens (pathophysiology)
Henoch-Schonlein purpura (HSP)
- IgA mediated small vessel vasculitis
- abnormal IgA deposition in the glomerulus
Features/ presentation of Henoch-Schonlein Purpura
Features
- palpable purpuric rash (with localized oedema) over buttocks and extensor surfaces of arms and legs
- abdominal pain
- polyarthritis
- features of IgA nephropathy may occur e.g. haematuria, renal failure, proteinuria
Management and prognosis of Henoch-Scholein** purpura
Treatment
- analgesia for arthralgia
- treatment of nephropathy is generally supportive.
- inconsistent evidence for the use of steroids and immunosuppressants
Prognosis
- usually excellent, HSP is a self-limiting condition, especially in children without renal involvement
- around 1/3rd of patients have a relapse
Answer
1. Diagnosis: Nephrotic syndrome -> minimal change glomerulonephritis
*we do not biopsy children - 90% will have minimal change
* treat with the steroids
- Possible complications are: pulmonary embolism, cellulitis, cerebral sinus thrombosis, peritonitis
* cellulitis and peritonitis (as immunoglobulins are lost as proteins in the urine -> prone to infection)
*not pulmonary oedema -> it depends on hydrostatic pressure; here it is lost (pt has low BP, less likely to get pulmonary oedema)-> so cannot force fluid into the lungs
What’s the commonest cause of nephrotic syndrome in the child?
Minimal change glomerulonephritis
- the underlying cause of glomerulonephritis in a child - unless proven otherwise
What’s the prevalence of minimal change disease?
Minimal change disease
- nearly always presents as nephrotic syndrome
- 75% of cases in children
- 25% in adults.
Possible causes of Minimal Change glomerulonephritis
The majority of cases are idiopathic, but in around 10-20% a cause is found:
- drugs: NSAIDs, rifampicin
- Hodgkin’s lymphoma, thymoma
- infectious mononucleosis
Pathophysiology of minimal change glomerulonephritis
Pathophysiology of minimal change glomerulonephritis
It is immuno- mediated but we do not know what in immune system causes it (according to the lecture)
PassMedicine notes:
- T-cell and cytokine mediated damage to the glomerular basement membrane → polyanion loss
- the resultant reduction of electrostatic charge → increased glomerular permeability to serum albumin
Features of minimal change glomerulonephritis
Features
- nephrotic syndrome
- normotension - hypertension is rare
- highly selective proteinuria*
- renal biopsy: electron microscopy shows fusion of podocytes
* only albumin and transferrin will leak through (due to their size)
Treatment of minimal change glomerulonephritis
Management
- majority of cases (80%) are steroid responsive
- cyclophosphamide is the next step for steroid resistant cases
Prognosis is overall good, although relapse is common. Roughly:
- 1/3 have just one episode
- 1/3 have infrequent relapses
- 1/3 have frequent relapses which stop before adulthood
Answer:
B. Lupus nephritis -> clue is in the Hx (e.g. Reynolds), discoid lupus - hair loss, bloods are low
*lupus affects lots of body system: joint pain, rashes, blood problems, psychiatric problems
Other investigation: look for ANA (90% of pt with lupus but not really lupus specific); look for dsDNA -> more positive for lupus
*also do kidney biopsy
Treatment for Lupus nephritis
Immunosuppression
- steroids
- cyclophosphamide
- Rituximab
- hydroxychloroquine)
Answer
- Diagnosis: Acute Post Strep glomerulonephritis (as 2 weeks after infections)
- Tests: suggestive of post strep
- glomerulonephritis -> serum complement & anti Dnase (anti - streptolysin anti-body -> as compotents of strep wall)
*some antigens in kidney look at streptococcus wall -> molecular mimicry
What’s the most likely diagnosis?
a) post strep glomerulonephritis
b) Lupus nephritis
c) IgA nephropathy
d) microscopic polyangitis
e) Good Pasture’s disease
Answer:
Good Pasture’s -> because it is positive for an anti-glomerular basement membrane antibody
X-ray: pulmonary haemorrhage
Goodpasture’s disease
- what is this (2 main features)
Pulmonary haemorrhage + rapidly progressive glomerulonephritis
What antibody causes Goodpasture’s syndrome? (pathophysiology)
Good Pasture’s syndrome
- caused by anti-glomerular basement membrane (anti-GBM) antibodies against type IV collagen
- this breaks basement membrane -> blood get into it and irritates it
*a lot of ‘crescents’ in the Bowman’s capsule forms -> nephron is gone
Goodpasture’s syndrome
- gender prevalence
- age distribution
- genetic association
Goodpasture’s syndrome
- more common in men (sex ratio 2:1)
- (peaks in 20-30 and 60-70 age bracket)
- associated with HLA DR2
Investigations for Goodpasture syndrome
Investigations
- renal biopsy: linear IgG deposits along basement membrane
- raised transfer factor secondary to pulmonary haemorrhages
Management of Goodpasture’s syndrome
Management
- plasma exchange (plasmapheresis)
- steroids
- cyclophosphamide -> alkylating agent -> immunosuppressant
What ocular abnormality is it connected with?
Diagnosis: Alport’s syndrome
Ocular abnormality: anterior lenticonus (protrusion of the lens surface into anterior chamber)
Alport’s syndrome
- gene
- defects (pathophysiology)
Alport’s syndrome
- 85% inherited in an X-linked dominant pattern
- 15% autosomal recessive
- defect in the gene coding for type IV collagen
Result: abnormal glomerular-basement membrane (GBM)
What features may be seen in Alport’s syndrome?
Alport’s syndrome usually presents in childhood. The following features may be seen:
- microscopic haematuria
- progressive renal failure
- bilateral sensorineural deafness
- lenticonus: protrusion of the lens surface into the anterior chamber
- retinitis pigmentosa
- renal biopsy: splitting of lamina densa seen on electron microscopy
What may happen with renal transplant in a patient with Alport’s syndrome?
Alport’s patient -> may fail renal transplant
- this may be caused by the presence of anti-GBM antibodies leading to a Goodpasture’s syndrome like picture
