nephrotic syndrome Flashcards
nephrotic vs nephritic syndrome
nephrotic: hypoalb (<25g/L), proteinuria (>200 Pr:Cr), oedema, hyperchol (>250dg/dL)
nephritic: haematuria, mild-mod proteinuria, HTN, oliguria, and red cell casts
two causes of benign, isolated proteinuria
- transient proteinuria: dehydration/exercise/illness/seizures/adrenergic meds –> just collect a morning rested sample
- orthostatic/postural proteinuria: tall adolescent males. glomerular.
idiopathic nephrotic syndrome: what main histologies?
85% minimal change disease (3+)
10-15% FSGS (6+)
define steroid dependent NS
2 consecutive relapses occurring while weaning to alternate day steroids or within 2 weeks of steroid discontinuation
histology of minimal change vs FSGS
MCD: podocyte effacement by electron microscopy
FSGS: segmental sclerosis of affected glomeruli, with the segment often adherent to Bowman’s capsule by synechiae
causes of non-idiopathic nephrotic syndrome
Infectious: MPGN e.g. HBV/HCV, HIV, toxo, post-infectious
Immune-mediated: lupus, IgA, HSP
Drugs: NSAIDs, bisphosphonates, lithium, rifampicin, sulfasalazine
Haem: sickle cell, thrombotic microangiopathy
Malignancy
name some features not consistent with nephrotic syndrome
Age <1 year or >12 years
Systemic symptoms – fever, rash, joint pains (SLE)
Persistent HTN – can have mild HTN first 1-2 days
workup in NS if suspicious of glomerulonephritis
C3/C4 - low in MPGN, SLE
ANA, anti-dsDNA -
ASOT and anti-DNase B for PSGN
ANCA - ANCA vasculitides e.g. Wegners
IgA, IgG, IgM for nephropathies
Infectious serology e.g. HIV, HCV, HBV
complications of nephrotic syndrome
Infection (leading cause mortality) – due to loss Ig, impaired opsonization/lymphocyte function - can present as peritonitis!
Thrombosis
Hypothyroidism – low TBG
Hypertriglyceridemia
Poor growth/nutrition/hypovolemia
…and AKI
idiopathic NS FSGS rule of 1/3
i. 1/3 improve
ii. 1/3 persistent heavy proteinuria
iii. 1/3 ESRF by 5 years
what percentage of NS will be steroid resistant at first presentation?
10-20%
5 major genetic causes of congenital nephrotic syndrome
NPHS1 = Finnish variant, encodes nephrin
NPHS2 = familial FSGS, encodes podocin
WT1 = Denys Drash
LAMB2 = Pierson, encodes laminin beta 2
NPHS 3 = encodes PLCE1
most common bacterial cause of SBP in NS
strep pneumoniae (hence the pen V)
define frequently relapseing NS
≥2 relapses within 6 months of initial response or ≥4 in any 12 month period
Rx we can give for SRNS
ciclosporin (FRNS), cyclophosphamide, tacro, ritux, levamisole
