Nephritic & Nephrotic Syndrome Flashcards
What are the 3 layers of the Glomerular Filtration Barrier?
Endothelial Cell layer - fenestrated
GBM - Type 4 collagen & laminin with embedded mesangial cells (smooth muscle)
Podocytes (Podocin & nephrin proteins)
Define Nephritic vs Nephrotic Syndrome?
Nephritic = High haematuria & intravascular overload
Nephrotic = High proteinuria & intravascular depletion
What would Nephrotic syndrome look like?
OEdema in face, legs, ascites and pleural effusions
~Raised BP
Frothy Urine
~Pale but mostly well
What causes Nephrotic Syndrome?
85% are Minimal Change Disease
15% are termed “Steroid REsistant nephrotic syndrome” which includes:
- Congenital NPHS1 or 2
- Acquired FSGS (Focal segmental glomerular sclerosis)
How do we confirm minimal change disease?
U&Es + Creatinine = Renal function should be normal
BP = Generally Normal
Urine Dipstix = high Protein & maybe haematuria
Trial Prednisalone
Why don’t we biopsy in most nephrotic syndromes?
Most it’s almost always minimal change disease so we just trial treatment
Nephrotic Syndrome is treated with 8wks of prednisolone. what are the major SEs?
Commonest: GI due to high acid Behaviour (irritable/moody/don't sleep) HTN Weight Gain
Uncommon:
Glucose intolerance
Adrenal crisis
Growth problems with recurrent courses
Describe the outcome of MCD?
95% go into remission in 2-4wks
80% will relapse
How do you treat Steroid Resistant Nephrotic Syndromes e.g. FSGS?
Second line immunosuppression
Try to list 8 major causes of childhood haematuria?
UTI
Trauma
Stones
Glomerulonephritis due to:
- Post-infective GN
- IgA nephropathy / HSP
- Membranoproliferative GN
- SLE
- ANCA +ve vasculitis e.g. GPA
What’s the classic presentation of Nephritic Syndrome?
- Haematuria (frank or microscopic)
- Proteinuria
Reduced GFR:
–> Oligura
–> Fluid overload (JVP/oedema)
–> HTN
–> High creatinine
Often comes post-infection, particularly throat
What’s the most common nephritic syndrome in kids vs adults?
Kids - Post-infective Glomerulonephritsi
Adults – IgA Nephropathy
What causes Post-infective Glomerulonephritis?
Group A strep
Throat infections 7-10days later
skin 2-4wks later
Nephrogenic strep antigens bind to sites in glomeruli & form immune complexes which are deposited there
This triggers Alternative Complement activation & Adaptive immune response leading to the nephritis
How can you diagnose Post-infective Glomerulonephritis?
A bacterial culture & throat swab for Strep A
+ve ASO Titre
Low C3 (used up)
Normal Renal US
ANA (SLE) + ANCA (GPA) to rule out autoimmune
So child with nephritic syndrome presents a week after having a throat infection.
Tests show Strep A culture, +ve ASO titre, low C3
Renal US, ANA & ANCA were all -ve
How would you treat the kid?
Diagnosis of Post-infective GN
Abx
Diuretic for fluid overload
Support renal function (e.g. restrict fluid, restrict Na, ACEI etc)
It will be self-limiting