PSGN

Question 1

You are seeing a 4 year old boy with his mother in clinic. He presented with a 24 hour history of generalised swelling (including periorbital adds sacral swelling) and lethargy. He has recently had a one-week history of an upper respiratory tract infection. His past medical history is unremarkable. His immunisations are up to date.

Answer 1

Impression
Given recent URTI and now generalised swelling (anasarca), am concerned about post-streptococcal glomerulonephritis. The other key differential in this population demographic is minimal change disease

I would want to consider and rule out other causes of generalised swelling including
- Liver: liver failure (infective cause)
- Renal: other causes of nephrotic syndrome (IgA nephropathy, focal segmental GN, membranous GN, minimal change disease, Alport’s syndrome and other secondary causes; diabetes, vasculitis, etc (less likely))
- Cardiac: acyanotic congenital heart disease (VSD, atrioventricular SD, PDA, etc, rheumatic heart fever.

Secnodary causes of nephrotic
- HSP
- SLE

Would also want to rule out nephritic syndrome as a potential cause.

Goals
- conduct targeted Hx/Ex/Ix
- manage appropriately, involve paeds nephrology early, manage complications appropriately

Question 2

PSGN - History

Answer 2

History
- characterise recent illness: pharyngitis? how long for, sx, treatment, sick contacts, full recovery? period of time between illness and current presentation?
- nephrotic: oedema, frothy urine, how rapidly progressing? Blood in urine (nephritic)
- risks: hx of atopy, indigenous background
- PMHx, immunosuppression, autoimmune disease, family history of nephrotic/renal disease. any cardiac/liver/other renal disease
- immunisations history
- Paeds hx

Question 3

PSGN - Examination

Answer 3

Examination
- generals + vitals
- systemic inspection for degree of oedema
- cardioresp (fluid on lungs, other complications - resp distress)
- skin: for evidence of pustules/sores/lesions
- Fundoscopy for any HTN changes as evidence of end-organ damage

Question 4

PSGN - Investigations

Answer 4

Investigations
- Bedside: UA (proteinuria 3+ diagnostic), uACR
- Bloods: UEC (renal function, creatinine), LFTs (hypoalbuminaemia), BNP, FBC, CRP/ESR, glomerulonephritis serology/screen - in particular ASOT titre (anti streptomycin O antibodies), hepatitis viral serology, CMP
- Imaging: renal tract US to evaluate for evidence of chronic renal disease
- Other: if diagnostic uncertainty then renal biopsy

Question 5

PSGN - Management

Answer 5

Management
Depends on underlying cause;
- Call paeds nephrology for consult and TOC

Supportive
- daily weights + UA (for a year or 2)
- strict fluid restriction
- salt restriction
- notify PHU

Definitive
Minimal change
- involve paeds nephrology
- corticosteroid therapy: induction dose 60mg/m^2/day pred PO, weaning every 4 weeks 90% will respond to initial therapy within 4 wks
- paeds nephrology referral
- daily urine testing to check for protein for entire year to check for relapse
- regular review, parent education
- IV conc albumin if severe oedema (under guidance of senior colleagues) +/- diuretics
- consider antibiotics if ongoing oedema- prophylactic penicillin until
- consider ACEi and statins (can get hyperlipidaemia)

PSGN
- Is supportive treatment as 95% will improve on their own, very rarely progresses to RPGN and renal failure (1%)
- typically occurs 2-4 weeks post GAS infection
-?hospitalisation if severe HTN associated
- if Indigenous: promote regular washing to reduce spread of bacteria