Chapter 20.1: Glomerulonephropathies Flashcards
Nephritic Syndrome
Process and Sx

Nephritic Syndrome
Glomerular diseases presenting with nephritic syndrome are often characterized by ________________ => nephritis, damaging the filtration barrier to __________
- Features: _______, ___________ (<3.5 grams/day), ______, ____; usually sicker/less sick than nephrotic
Glomerular diseases presenting with nephritic syndrome are often characterized by inflammation in the glomeruli => nephritis, damaging the filtration barrier to RBC and proteins.
- Features: Hematuria, mild proteinuria (<3.5 grams/day), azotemia, HTN; usually sicker than nephrotic
Major causes of Nephritic Syndrome
- Acute/Diffuse proliferative (post-streptococcal) glomerulonephritis
- RPGN
- Berger’s IgA nephropathy
- Alport Syndrome
Acute (Diffuse) Proliferative Glomerulonephritis is a _______ syndrome and is a __________ hypersensitivity reaction.
Nephritic
Type 3 (Immune complex)
Acute (Diffuse) Proliferative Glomerulonephritis is what, that typically occurs when, in who?
- Inflammation of the glomeruli after group A B-hemolytic strep infection in children and young adults, but may occur after infection with many other organisms. Usually FTER,
- Impetigo (skin)
- Pharyngitis (strep)
Strep can lead to rheumatic fever and post-strep GN.
Can patients develop both?
No.
- Certain strep bacteria are nephritogenic strains, which are specific types of M protein virulence factor.
- Subtype: lancefield group A.
What is the pathology of Acute (Diffuse) Proliferative Glomerulonephritis?
Group A B-Hemolytic Strep causes?
How do lesions form?
- 1-4 weeks AFTER Group A B-hemolytic strep => causes diffuse proliferation of glomerular cells and influx of leukocytes in all glomeruli
- Lesions formed when:
- [IgG/M Ab] against [step pyogenic exotoxin B (SpeB)] antigen =>
- in-situ formation of immune-complexes in the subepithelium (with many neutrophils).
- => inflammatory reaction, which involves + compliment (C3) and attracts PMNs, which damage podocytes
- Leads to hypocomplementemia, because it degrades the body of compliment proteins.
In acute proliferative glomerulonephritis, in-situ immune complexes that form in _________ spaces will do what?
- Subepithelial
- => inflammation => + compliment & attract PMNS =>
Acute (Diffuse) Proliferative Glomerulonephritis
- Light microscopy:
- Electron microscopy:
- IF:
- Light Microscopy: Hypercellular & enlarged glomeruli (d/t proliferation of endothelial/mesangial cells) and many leukocytes (d/t inflammation)
- Not specific
- Electron Microscopy: Subepithelial humps of immune complexes
- DIAGNOSTIC of POST-STREP GN
- Immuno-Fluorescence: “starry sky”; granular deposits of IgG, IgM and C3 in mesangium and along GBM

Acute (Diffuse) Proliferative Glomerulonephritis is most common in who?
Children (6-10); more atypical and aggressive in adults
How is acute proliferative GN different in children and adults
- More atypical and aggressive in adults => causes sudden HTN, edema, high BUN
- Recovery
- 95% recovery in children; 60% recovery in adults
- Takes adults longer to heal
- More progress to chronic glomerulonephritis or RPGN type 2(10%)
Acute/diffuse proliferative GN is most likely to occur in children (6-10) ___________ after a strep throat/skin infection (impetigo) due to ab to ________.
- 1-4 weeks (thus, pt will have no sx)
- SpeB (streptococcal pyogenic exotoxin B)
- How does Acute Proliferative (Poststreptococcal) Glomerulonephritis typically present (signs/sx’s and findings)?
- Urine?
- 1-4 weeks AFTER infection, child (6-10 YO) will have fatigue + fever + nasuea + oliguria + hematuria and sx of nephritic syndrome
- Urine: red cell casts, dysmorphic RBCs
*
Blood tests of patient with acute proliferative (post-strep) glomerulonephritis will have what findings?
- + ASO titers for Strep (Antistreptolyosin O Ab), anti-DNaseB
- low compliment levels
What is the outcome of children with Acute (Diffuse) Proliferative Glomerulonephritis d/t strep?
- 95% recover w/ conservative therapy (water and salt restriction) (<1% progress to RPGN Type II)
- Acute proliferative GN does not have to occur d/t strep => Acute proliferative glomerulonephritis (post-infectious and non-streptococcal) can occur d/t what else?
- 1. Bacteria
- 2. Viral
- 3. Parasites (toxoplasmosis and malaria)
How do the immune deposits found in postinfectious GN due to staphylococcal infection differ from that of strep?
- immune deposits have IgA, not IgG
- NOTE: Distractor! if there is a current complaint of sore throat and dry cough it is what can we exclude
PSGN: happens 1-4 weeks after an untreated case
Rapidly Progressive Glomerulonephritis (RPGN) is a _______ syndrome and a __________ hypersensitivity reaction.
Nephritic
Type 2 (immune complex)
What is Rapidly Progressive Glomerulonephritis (RPGN)?
- A severe form of glomerulonephritis where inflammation can lead to renal failure in weeks - months
- Caused by:
-
Cell-mediated immune response and MO cause BM to tear
- RBC, inflammatory mediatorys (=> inflammation) plasma proteins, fibrin, monocyte/MO & parietal epithelial cells leak out into Bowmans space =>
-
Parietal epithelial cells, MO/monocytes, fibrin & thrombin** => formation of **crescents in Bowmans space (causing normally thin epithlial layer to thicken and necrosis.
*
-
Cell-mediated immune response and MO cause BM to tear
What makes up crescents in RPGN?
How do we view them?
- Proliferation of parietal epithelial cells that line Bowman’s capsule, monocytes, MO, and fibrin
- PAS stain on LM
What occurs due to the damage induced in RPGN?
- Rapid obliteration of urinary space => rapid and progressive loss of renal function,
- Severe oligaria
- Tears in BM => cause RBCs to squeeze throuhh and NTR urinary space => hematuria
- Renal failure in weeks to months
What symptoms can we see in a patient that we suspect has RPGN before conducting a renal biopsy?
1. Nephritic urine (RBC in urine)
2. Fatigue and anorexia
3. Acute renal failure

Causes of RPGN are distinguished based on what?
IMMUNOFLUORESCNCE
What do we see on LM, EM in a patient with RPGN?
- Light microscopy: Crescents & MO/leukocyte infiltration
- Electron microscopy: wrinkling/tearing of GBM and RBC can often be seen scooting into urinary space
Causes of RPGN are distinguished based on immunofluorescence.
How do we do so?
- RPGN Type 1: Linear IF
- RPGN Type 2: Granular IF
- RPGN Type 3: Negative IF
RPGN Type 1 (______)
RPGN Type 2 (______)
RPGN Type 3 (______)
RPGN Type 1 (anti-GBM)
RPGN Type 2 (Immune complex)
RPGN Type 3 (Pausi-immune)
Type I RPGN (anti-GMB Ab) disease is characterized by what kind of deposits?
Why this pattern?
-
Linear deposits of anti-GM antibodies (IgG and C3) in the GBM of kidney and lung.
- Linear bc binds to intrinsic Ag along ENTIRE length of GBM
- RPGN Type I (Anti-GBM Antibody) occurs when…
- anti-GBM antibodies against GBM antigens deposit in the BM
_______ is an example of a disorder than can cause RPGN Type I (anti-GBM Ab).
Goodpastures
Goodpastures syndrome can cause RPGM Type 1 (anti-GBM Abs).
What antigen will the anti-GBM Abs attack?
- [non-collagen portion of a-3 chain of type 4 collagen] in the GBM and alveoli
RPGN Type 1 that occurs in Goodpastures syndrome causes what symptoms?
- Hemoptysis due to pulmonary hemorrhage
- Hematuria
- Nephritic syndrome
Which HLA subtype is associated an increased liklihood of getting RPGN (i.e., Goodpasture Syndrome)?
HLA-DRB1
What is used in the treatment for Type I RPGN (anti-GBM Ab disease)?
How effective?
- Plasmapheresis + immunosupressive therapy
- Can reverse pulmonary hemoorhage and renal failure
- Type 2 RPGN (immune complex mediated) disease is characterized what pattern of IF?
- Where do the immune complexes deposit?
Subendothelial Granular due to deposition of immune complex
& cell proliferation
Major causes of Type II (immune complex) RPGN?
Occurs due to the progression of
- Post-infection GN (post-strep acute proliferative GN)
- SLE
- IgA Nephropathy
RPGN Type 2 (Immune complex) is a type ____ hypersensitivity reaction.
ignore until further notice.
3
Can Type II RPGN be treated by plasmapheresis?
No; treat underlying disease
Type 3 RPGN disease is characterized by what kind of deposits?
- NO [anti-GBM Ab & immune complexes] because of a pausi-immune response.
Presence of what in the serum is virtually diagnostic of Type III (Pauci-Immune) RPGN?
p/c-ANCA (anti-neutrophil cytoplasmic Ab)
Type III (Pauci-Immune) RPGN may occur due to underlying disorders?
-
Vasculitis syndromes, such as
- Wegener (c-ANCA)
- Microscopic Polyangiitis and Churg Strauss (pANCA)
In RPGN what is commonly seen in prominent amounts between the cellular layers in crescents?
Fibrin
Rapidly progressive glomerulonephritis can evolve into _________ or lead to what?
- Chronic glomerulosclerosis**
- Renal failure in weeks => months
In nephrotic syndrome, what barrier is lost?
Barrier to proteins (podocytes/epithlielial cells); RBC filtration barrier (endothelium) is intact.
- Most causes of nephrotic syndrome are related to damage of what?
- Podocytes (epithelial cells) => protein loss only
- Endothelial cells (RBC barrier) are intact
Does inflammation occur in nephrotic syndromes?
NO
What causes nephrotic syndrome, resulting in proteinuria?
And if indicated, what are they due to?
-
Primary
- Minimal change disease: cytokines
- Focal segmental glomerulosclerosis (FSGS): podocyte damage
-
Membranous nephropathy: immune complexes
- Diabetic: glucose
-
Systemic causes
- Membranoproliferative glomerulonephritis
Nephrotic syndrome in US kids less than 17YO is due to what?
To primary lesion of the kidney
What primary lesion is most common in children?
Minimal change disease (75% of cases in children)
How does the cause of nephrotic syndrome in children <17 yo differ from adults?
- Children = almost always caused by a lesion primary to the kidney
- Adults = often associated with a systemic disease
What are the 3 most common primary glomerular lesions responsible for the development of nephrotic syndrome?
Which is most common in children and which in adults?
- Minimal change disease = most common in children (75%)
- Membranous glomerulopathy = most common in older adults
- Focal segmental glomerulosclerosis = occurs at all ages
What are the most frequent systemic causes of nephrotic syndrome?
- - Diabetes
- - Amyloidosis
- - SLE
- Drugs
- Infections
- Malignant dz (carcinoma, lymphoma)
How should we treat nephrotic syndrome in children?
- Nephrotic syndrome in children is minimal change disease** until proven otherwise; **don’t biopsy – tx with steroids and see if condition improves because MCD responds to steroids.
In one word, what is the cause of
- 1. Minimal Change Disease
- 2. Focal Segmental Glomerulosclerosis
- 3. Membranous Nephropathy
- Minimal Change Disease
* Cytokines
- Minimal Change Disease
- Focal Segmental Glomerulosclerosis
* Podocyte damage
- Focal Segmental Glomerulosclerosis
- Membranous Nephropathy
* Immune complexes
- Membranous Nephropathy
What does the term “nephrotic range proteinuria” refer to?
Loss of 3 grams or more/day in the urine
- ___________ is the 2nd most common cause of nephrotic syndrome in adults (30%)
Membranous Glomerulopathy (nephropathy)
FSGS (35%) is most common.
What is membranous nephropathy?
- Chronic immune-complex mediated disease that causes diffuse thickening of the glomerular BM (without hypercellarity) due to deposits of IgG on subepithelial side of the BM.
Most causes of membranous glomerulopathy are primary/secondary
Primary (75% of cases)
Primary membranous glomerulopathy is now considered an autoimmune disease and linked to which HLA allele?
HLA-DQA1
Primary membranous glomerulopathy is a diffuse thickening of the glomerular BM (without hypercellarity). How does this happen?
-
IMMUNE COMPLEXES:
- autoAB to phospholipase A2 receptor (PLA2R) antigens (or neutral endopeptidase in secondary) on the podocytes => form subepithelial immune complex deposits (primarily IgG4)
-
=> Leukocyte infiltration and activate compliment =>
- MAC causes capillary wall to become leaky => proteins leave
- Damage to podocytes and mesengial cells => effacement
- Overtime, podocytes lay extra BM => thickening of BM (but no hypercellularity) between immune complexes=> creating a spike and dome appearance

How is Membranous Glomerulopathy different from Minimal Change Disease?
- Membranous Glomerulopathy does NOT respond to steroid therapy.
- MCD does.
What appearance does membranous glomeruleropathy create?
- Spike and dome appearance due to thickening of glomerular BM (but no hypercellularity).

If thickening of the BM occured + hypercellularity, what nephropathy would this be?
Membranoproliferative glomerulonephritis
Membranous glomerulonephropathy
- LM
- EM
- Immunoflourescence
- LM: Uniform, diffuse thickening (no hypercellularity) of BM on PAS stain
- EM:
- [Spike and dome pattern]: subepithelial deposits of IgG4 on silver stain
- [Effaced (Flattened) foot processes]
- IF: “Lumpy bumpy” IgG4 granular deposits

What are some of the secondary causes of Membranous Nephropathy?
“TUMOR, HEPATITIS, RHEUMATOID ARTHRITIS”
- 1. Drugs used to tx RA
- 2. Malignancies
- 3. Infections (hepB/C)
- 4. SLE, Autoimmine disorders
Secondary membranous glomerulonephritis is more likely to experience _______.
Hematuria
Describe the proteinuria experienced in membranous glomerulopathy
Non-selective
Recurrence of Membranous Nephropathy is a common feature in which patients?
1. Transplant pts for end-stage renal disease
- Women have spontaneous remissions and more benign outcome
What is the prognosis of membranous glomerulonephropathy in children?
What can MGN result in?
- Good prognosis in children
- 60% of pts => proteinuria persists
- 40% => renal insufficiency
- 10% => ESRD
How is minimal change disease different from membranous glomerulonephropathy in regards to the proteins that leak out?
- Minimal change disease: selective proteinuria (only albumin)
- Membranous glomerulonephropathy: non-selective proteinuria (albumin AND Ig)
Minimal change disease is also called _________.
Nil disease.
What is minimal change disease?
How does it occur?
Nephrotic syndrome where foot processes of the podocytes are damaged, allowing albumin to leak out of the capillary => urinary space.
-
MOA:
- T-cells release cytokines,
- Damage
* damage the (-) charge on podocytes
* effacement (flatten & fusion of) foot processes
- Damage
- Selective proteinuria
- (-) charged albumin leaks out => ↑ albumin in the urine => nephrotic syndrome

Minimal Change Disease
- LM
- EM
- Immunoflourescence
FINDING ONLY ON EM!
- LM: NL
- Immunofluorescence: NL bc damage is d/t cytokines
- EM: Effacement (flatten and fusion) of foot processes, but glomeruli is NL.

Minimal Change Disease is most offten seen in who?
What condition is it often a cause of?
- Children 2-6
- Hodgkins Lymphoma and lymphoreticular disorders, which release MASSIVE amounts of cytokines.
What is main presenting sign in MCD?
What sx RARELY develops?
- Edema
- Rarely develop HTN
Minimal change disease often has a __________, which causes the release of cytokines.
Immunological trigger
- Viral infection (URI)
- Allergic reaction
- Recent immunization
How do we treat MCD?
- Corticosteroids and immunosuppressants – very responsive (90% of children)
What are 5 features of minimal-change disease which point to an immunologic basis for its development?
Increased incidence in pts with what conditions and cancer?
- Occur after: URI and immunizations
- Responds to corticosteroids
3. Assoc. w/ atopic disorders (i.e., eczema, rhinitis)
- Increased prevalence of certain HLA haplotypes
- Increased incidence in pts w/ Hodgkin lymphoma
What is the SEVERE version of minimal change disease?
Focal Segmental Glomerulosclerosis (FSGS)***
What is the most common cause of nephrotic syndrome in adults U.S. AND WESTERN SOCIETY (35%)?
_Focal Segmental Glomerulosclerosis (FSGS)***_
FSGS is usually primary/secondary, but there are many ______ causes.
Often, it is a adaptive response to what?
FSGS is usually primary (idiopathic) but there are many secondary causes.
Often, a response to a loss of renal mass
What are the secondary causes of FSGS?
-
1. HIV (collapsing variant of FSGS):
- African Americans > Caucasians
- 2. SS (Sickle Cell)
- 3. Heroin
- 4. Massive obesity
What is FSGS and how does it occur?
- Unknown causes (idiopathic) damage podocyte => proteinuria.
- Overtime, proteins and lipids get trapped & build-up in the glomerulus => resulting in hyalinosis => sclerosis
- Sclerosis => collapse of the BM in a segment of some glomeruli (focal) in the kidney

Where does the damasge occur in FSGS?
Segments of SOME glomeruli, not all are affected.
FSGS
- LM
- EM
- Immunoflourescence
- LM: Hylanosis and sclerosis of a segment of a glomeruli in SOME glomeruli
- EM: Effacement of foot processes; sclerosis
- Immunoflourescence: sometimes focal deposits of IgM and compliment

What is the ONLY way to dx FSGS?
BIOPSY
Which populations have a higher incidence of primary Focal Segmental Glomerulosclerosis (FSGS)?
1. African Americans
2. Hispanics
The clinical signs of FSGS differ from Minimal Change disease in what 4 ways?
- Higher incidence of hematuria, reduced GFR and HTN
- Proteinuria is often nonselective
- Doesn’t respond well to steroids
- Poor prognosis: can progress to CKD ==> 50% developing ESRD within 10 years
What is the most characteristic lesion (i.e, morphological variant of FSGS) seen in HIV-associated nephropathy, a type of FSGS.
Collapsing glomerulopathy = severe form of FSGS
What is the prognosis of FSGS in children vs. adults?
- Children generally have better prognosis than adults
FSGS is nephritic/nephrotic?
Can be considered MIXED; nephrotic sydrome w nephritic characteristics
The collapsing variant of FSGS in HIV patients is most common in what population?
African American
Is Membranoproliferative Glomerulonephritis (MPGN) a disease?
No, it is a type of injury d/t immunity.
- Membranoproliferative glomerulonephritis (MPGN) is a group of rare glomerular disorders that can cause _________ syndrome. What occurs?
Nephritic or nephrotic syndrome
- Infiltration of acute inflamm cells (neutrophils)
- Thickening of BM
-
Hypercellularity: mainly mesangial, but can also be capillary
-
Capillary loops
mesangial: mesangial interposition occurs, where mesangial cells proliferate & extend into the thickened BM => splits BM (producing “double countour”), forming a “tram track appearance” on LM - Increases mesangial matrix
-
Capillary loops
MPGN causes varying degrees of renal dysfunction, such as:
- 1. Renal failure (high BUN and creatinine)
- 2. Proteinuria
- 3. Hematuria
- 4. Thick BM, hyperceullarity
In MPGN, how will the architecture of the lobules change?
They will become more accentuated.
Membranoproliferative Glomerulonephritis (MPGN) is also called ___________ glomerulonephritis.
Mesangiocapillary
What is the difference in the pathology of MPGN Type 1 and MPGN Type 2?
- MPGN Type 1: subendothelial immune complexes deposits that contain IgG and compliment
- MPGN Type 2: electron dense deposits of C3 (compliment) in the BM, not subendothelium
What are the differences between Type 1 and Type 2 Membranoproliferative Glomerulonephritis?
- Only difference (in terms of pathology) is where deposits are:
-
MPGN Type 1 (most common): Deposition of IgG/compliment immune complexes in the subendothelium
- tram-track appearance
- MPGN Type 2 (Dense Deposit Disease): deposition of C3a/C3b deposits in the BM (not subendothelium) and decreases levels of C3
-
MPGN Type 1 (most common): Deposition of IgG/compliment immune complexes in the subendothelium
What causes the C3 deposits in the BM in MPGN Type 2 (dense deposit disease)?
-
C3 nephritic factor (C3NeF, an IgG autoAb)) inapprop activates the alternative compliment pathway
- Binds to C3 convertase => stabilizes => prolong activation => increase C3a and C3b
- => deposit in BM
- => inflammation in BM and low levels of C3
Which causes tram track appearance MPGN Type 1 or Type 2?
Both
When do most cases of primary MPGN Type I present?
How do they present?
- MC in children or young adults mostly, but can affect all ages
- Nephrotic syndrome & nephritic component manifested by:
- Proteinuria, microscopic hematuria, HTN (~30), oliguria, some edema, and renal insufficiency
About 50% of patients with MPGN Type I will develop what?
Response to immunosuppressant therapy?
- Chronic renal failure in 10 years
- Not proven to be beneficial
Who does secondary MPGN Type I present in?
Arises in which settings and with what associated disorders?
- Almost exclusively in adults
- Arises d/t chronic antigenemia (from infection, autoimmune dz or neoplasia), which causes immune complex deposition
- SLE, HBV, HCV (w/ cryoglobulinemia), endocarditis, HIV, and schistosomiasis
- - α1- antitrypsin deficiency
- Malignancies (CLL, lymphomas, melanomas)
Most patients w/ dense deposit disease (aka type II MPGN) have abnormalities reulting in excessive activation of?
Alternative complement pathway
Dense deposit dz (MPGN type II) primarily affects whom?
Only occurs as what kind of disease?
- Children
- Only occurs as a primary renal disease; no secondary form
What is the dominant clinical finding in Dense Deposit disease vs. MPGN type I?
Prognosis of MPGN II vs. MPGN I?
- MPGN type 1: proteinuria
- MPGN type 2: hematuria
- 50% of patients will also have nephritic syndrome and 50% will get ESRD in 10 years
- Poorer prognosis than MGPN I due to most pts having severe renal dz.
High incidence of recurrence of MPGN II in which patients?
Transplant patients, indicating importance of a circulating factor
In MPGN 1 & 2, on LM we see (hypercellularity, GBM splitting, leukocyte infiltration and tram-track appearance)
What do we see on EM and IF for each?
Type 1
- EM: subendothelial deposits of immune complexes
- IF: IgG, C3; C1q and C4
Type 2
- EM: electron dense deposits in BM that look like ribons (seen in pic)
- IF: C3 and properidin (no IgG, C1q or C4)
*

What is the most common type of glomerulonephritis worldwide?
What about in the US?
- IgA nephropathy: worldwide
- FSGS: USA
What is IgA nephropathy (Berger Disease)?
- a overactive immune system that causes an ↑ IgA production, forming of IgA-IgG immune complexes in response to triggers such as:
- Respiratory infection
- GI infection
IgA nephropathy is an overactive immune system that produces excessive IgA, due to what?
Viral (MC) infections
- Respiratory infection
- GI infection
IgA-IgG immune complexes cause pathology and inflammation where?
Where they deposit (mesangium)
IgA-IgG immune complexes form in the mesangium. What happens next?
- => Light + of compliment pathway via alternative and lectin pathway (no hypocomplementemia)
- => Inflammation due to release pro-inflammatory cytokines and MO => damage of glomerulus
Will a person with IgA nephropathy develop hypocomplantemia? Why
No because compliment is LIGHLTY activated
IgA nephropathy is primarily a disease seen in whom?
Which ethnicities more affected?
Which sex?
- Older children and young adults (20s-30s)
- White ppl and Asians > African Americans
- Male predominance: 2:1 or higher (N. America and Europe)
What are the MAIN pattern of of IgA nephropathy (Berger disease)?
IgA1-IgG immune complex deposition in mesangium (GLOBAL) with only recurrent microscropic/gross hematuria for a long time (20 years), before developing into chronic renal failure.
IgA Nephropathy (Berger Disease)
- LM
- EM
- IF
- LM: Focal proliferation and widening of the mesangium
- EM: Mesangial and paramasangial dense deposits
- IF: Granular IgA-IgG immune complexes, IgM and C3 in the mesangium
- No C1q or C4 bc altenrative path was +
Due to increased synthesis of abnormal IgA, there is an increased incidence of IgA nephropathy seen in which 2 conditions?
- Celiac disease (gluten enteropahty)
- Liver disease (defective hepatobiliary clearance of IgA) –> secondary IgA nephropathy
Pts with IgA nephropathy commonly present with hematuria following what?
How long does it last?
- Respiratory infection or, less commonly the GI/GU tracts
- Hematuria lasts several days, then subsides, only to return every few months since childhood
What clinical outcome occurs in a majority of patients with IgA nephropathy?
- Recurrent episodes of hematuria w/o progression of renal disease
What are the clinical outcomes of IgA nephropathy progressing to a renal disease?
- 5-10% of patients will progress to acute nephritic syndrome w/ HTN
- 15-40% will progress to chronic renal failure over 20 year period
- Post-strep GN: occurs _____ after infection
- Minimal change: occurs:
- IgA Nephropathy: occurs:
- weeks
- nephrotic syndrome after URI
- recurrent episodes of gross/microscopic hematuria since childhood, URI, diarrhea
IgA nephropathy without extra renal involvement is called __________.
What about if there is extra-renal involvement?
- Berger Disease
- Henoch-Scholein Purpra (HSP
What is Henoch-Schonlein purpura (HSP)?
Typical clinical presentation?
- IgA nephropathy associated w/ systemic disease –> onset following URI
- Presents w/ cramping & pain + hematuria and proteinuria
What is an isolated glomerular abnormality?
IgA Nephropathy, because patient can be asymx for a LONG TIME
If a pt presents with glomerulonephritis syndrome with hypocomplimentemia, what is the most common dx?
- Membranoproliferative GN Type 2
MPGN Type 1 and 2: which is more a nepritic/nephrotic syndrome
- Type 1: nephrotic syndrome w nephritic findings
- Type 2: nephritic
Is Chronic Glomerulonephritis a diagnosis?
Yes
Chronic Glomerulonephritis causes what?
- Chronic renal failure/ chronic kidney disease
What stain is used to view Chronic Glomerulonephritis and what is seen?
_Trichome stain (_stains blue) shows obliteration and replacement of all glomeruli with acellular eosinophillic masses.
Do we always know what causes chronic glomerulonephritis?
NO. Many cases arise mysteriosly due to the end-result of relatively asymptomatic forms of glomerulonephritis that progress to uremia.
What PRIMARY glomerular disease most commonly become chronic glomerulonephritis (CGN)?
- 90% of Cresenteric GN
- 50-80% of FSGS
- 50% of membranoproliferative
- 30-50% of IgAN and membranous nephropathy
- 1-2% of post-strep GN
What are the 2 hereditary nephritis?
- Alport syndrome
- Thin Basement Membrane Disease (Benign Familial Hematuria)
80% of patients with a family history of hematuria or recurrent hematuria during childhood have either
- Alport
- Thin Basement Membrane Disease (more likely).
Alport & Thin Basement Membrane Disease are both isolated glomerular abnormalities and associated with mutations in in what gene?
Where in the kidney do we see the problem?
- Collagen gene that effect collagen
- Reflected by abnormalities of the BM.
What is Alport syndrome?
- A multi-system disease that produces a nephritic syndrome: hematuria that progresses into chronic renal failure.
What symptoms are associated with Alport?
- Triad (cant pee, cant see, cant hear a bee)
- 1. Hematuria that progresses into chronic renal failure.
- Hearing loss
- Eye disturbance
What is the major inheritance pattern of Alport Syndrome?
How does this effect the presentation in men and women?
X-linked (more common in Males)
Alport Disease is due to mutations in genes encoding subunits of which molecule?
COL4A5 (type 4 collagen, alpha5 chain)
Alport Syndrome
- LM
- EM:
- Immunohistochemistry:
- LM: NL (until late in the disease)
-
EM: Basket weave appearance
- Irregular thickening of BM with alternating attenuation (thinning)
- Splitting/lamination of the lamina densa, and foci of rarefaction
- IF: absence of a3, a4, and a5 staining
Symptoms of Alport Syndrome typically manifest btw what ages?
Frequent presentation?
- 5-20 yo w/ onset of overt renal failure btw ages 20-50
- Present w/ hematuria with red cell casts
What is Thin Basement Membrane Disease?
Hereditary disorder that causes asymptomatic microscopic hematuria due to a thin BM (150-250 nm, compared to 300-400 nm) and rarely leads end-stage disease
What is renal function like and the prognosis for TBM Disease?
NL kidney function and excellent prognosis
Which is more likely to lead to chronic renal failure/ESRD: Alport or TBMD?
- Alport.
- TBMD rarely leads to ESRD.
The thin BM’s in Thinned BM Disease is due to mutations in genes encoding what?
Most patients are what type of carriers?
- Type IV Collagen – a3 or a4 chain gene mutations
- Heterozygous carriers
Homozygotes with Thinned BM Disease resemble what other hereditary nephritis?
AR Alport
Which stain is used to view Chronic Glomerulonephritis?
What’s seen?
- Trichrome stain
- Shows:
- replacement of almost all glomeruli w collagen
-
obliteration of glomeruli with acellular masses of eosinophils
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As glomeruli progressively become obliterated in chronic GN, what happens to GFR and protein loss?
- GFR decreases
- Protein loss in urine diminshes