SM 205: Renal Syndromes

Question 1

Types of Casts and what they represent

Answer 1

RBC Casts: Glomerular Hematuria = Nephritic Syndrome

Lipid Casts: Nephrotic Syndrome

Question 2

Components of a Renal Biopsy

Answer 2

1. LM - look for cell proliferation, GBM abnormalities, lesions/necrosis
2. IF/IM - Ig/Complement Staining
3. EM - look for IC deposits, GBM thickening, podocyte foot process abnormalities

Question 3

What are the 5 key findings in Nephrotic Syndrome?

Answer 3

1. Proteinuria > 3g/day
2. Hypoalbuminemia
3. Hyperlipidemia
4. Lipiduria
5. Edema

Question 4

Minimal Change Disease (Type of Renal Syndrome, Population affected, Presentation, Biopsy Findings, Treatment)

Answer 4

Nephrotic
Pop: KIDS
Presentation: sudden-onset edema + other nephrotic features (sometimes following infection)
Biopsy: normal LM, negative IM, EM shows diffuse podocyte foot process effacement
Tx: Steroid responsive!

Question 5

Focal Segmental Glomerulosclerosis (Type, Population, Cause, Presentation, Biopsy, Tx)

Answer 5

Type: Nephrotic
Population: African Americans
Cause: APOL1 mutation, primary, 2/2 HIV/heroin/low kidney mass/obesity
Presentation: HTN, edema, proteinuria +/- hematuria
Biopsy: LM - focal, segmental lesions
IF - nonspecific staining of IgM/c’
EM - podocyte foot process effacement
Tx: HARD, tx secondary cause, or try steroids + chemotherapy

Question 6

Membranous Nephropathy (Type, Population, Cause, Biopsy, Tx)

Answer 6

type: Nephrotic
Population: Caucasian Adults
Cause: Primary, 2/2 Solid cancer tumors, meds (NSAIDS), Infection (HEP B/C), Autoimmune (SLE)
Biopsy: LM - thickened GBM, silver stain has “spikes and holes”
IF - granular IgG
EM - subepithelial immune deposits
Tx: treat secondary cause, RAAS blockade (ACE-i/ARB) if low proteinuria, immune modulation if high proteinuria

Question 7

Clinical Findings of Nephritic Syndromes (4)

Answer 7

1. Hematuria
2. Dysmorphic RBCs +/or RBC Casts
3. Proteinuria (non-nephrotic)
4. Varying degrees of renal insufficiency, HTN, edema

Question 8

Key finding for rapidly progressing glomerulosclerosis

Answer 8

CRESCENTIC GN on biopsy

Question 9

Anti-GBM Disease

Type, Findings, Sx, Labs, Biopsy, Tx

Answer 9

Nephritic
Auto-antibodies bind type IV collagen in GBM (and lungs involved = Goodpasture’s diseasE)
Sx: malaise, weight loss, hemoptysis
Labs: +anti-GBM antibody!!! hematuria, proteinuria, rising Scr
LM - diffuse crescentic GN
IF - LINEAR IgG staining
Tx: Aggressive: Steroids + cyclophosphamide (chemotherapy) + plasmapheresis (take ICs out of blood)

Question 10

Post-Infectious GN

Type, Findings, Sx, Labs, Biopsy, Tx

Answer 10

Nephritic (high ICs)
Onset 10-14 days after Strep pharyngitis/skin infection
Sx: gross hematuria, fever, malaise, HTN
Labs: high SCr, hematuria, proteinuria, LOW C3/C4, maybe +ASO TITER
LM - hypercellularity
IF - “Starry sky”
EM - subendothelial humps
tx: support infection (ABx); steroids if severe kidney involvement

Question 11

Lupus Nephritis

Type, Findings, Sx, Labs, Biopsy, Tx

Answer 11

Nephritic (high ICs)
Usually younger women with known SLE
Sx: malaise, joint pain, face rash, oral ulcers, serositis, edema
Labs: Low C3/C4, +ANA, +dsDNA
Biopsy - 6 classes of differentiation
Tx: supportive, if severe, do high-dose steroids and immune modulating drugs

Question 12

IgA Nephropathy

Type, Findings, Sx, Labs, Biopsy, Tx

Answer 12

Nephritic (high ICs) - most common one
2/2 inflammatory bowel, cirrhosis or primary
Sx: hematuria immediately or 1-2 days after URI/diarrheal illness
Labs: normal C3/C4, variable proteinuria
LM - mesangial proliferation
IF - + IgA
Tx - ACE-i/ARB if mild, Steroids/Immunosuppressive if high risk

Question 13

Membranoproliferative GN

Type, Findings, Sx, Labs, Biopsy, Tx

Answer 13

Nephritic (high ICs) - pattern, not specific disease
Assoc. w/ underlying infection (Hep C)
Sx: Nephritic or Nephrotic features
Labs: High SCr, Low C3
LM - lobular glom, Silver stain “tram-tracks”
IF - C3 + IgG Staining
EM - various IC deposits
Tx: treat Hep C if associated, otherwise poor prognosis

Question 14

Granulomatosis with Polyangiitis (GPA)

Type, Findings, Sx, Labs, Biopsy, Tx

Answer 14

Nephritic (few ICs) - type of vasculitis (AKA Wegener’s disease)
Pulmonary-renal syndrome - older pts
Sx: constitutional (fever, malaise, weight loss), nasal/sinus sx, saddle-nose, purpura, pulmonary infiltrate/hemorrhage
Labs: +c-ANCA (+PR3)
Biopsy: CRESCENTIC GN
tx: high dose steroids + cyclophosphamide

Question 15

Microscopic Polyangiitis (MPA)
(Type, Findings, Sx, Biopsy, Tx)

Answer 15

Nephritic (few ICs) - type of vasculitis
Pulmonary-renal syndrome - older pts
Sx: constitutional, lower resp tract hemoptysis
Labs: +p-anca, (+MPO)
Biopsy: CRESCENTIC GN
Tx: high dose steroids + cyclophosphamide