Ch 16: Kidney- Glomerular Diseases (Part 2) and Vascular Disease Flashcards
Presents as isolated hematuria, sensory hearing loss, and ocular disturbance.
What is the inherited defect?
What happens to the GBM?
When is hematuria present?
What develops later in the course of the disease and by age 40-50 years?
Alport Syndrome (aka Hereditary nephritis)
Type IV Collagen
Splitting, thinning
Early in life for males with X-linked disease, both sexes with AR disease
Proteinuria, progressive renal failure, HTN, end stage renal disease
How can you remember the features of nephritic syndrome?
PHAROAH
= Proteinuria, Hematuria, Azotemia, RBC casts, Oliguria, Anti-strep titres (if post-strep), and Hypertension
And also DECREASED GFR due to glomerular inflammation: infiltration by leukocytes, hyperplasia of glomerular cells, necrosis
Which group and hemolytic class of microbe most likely causes postinfectious GN?
What is the usual precipitating infection called?
What is the mechanism of injury causing glomerulonephritis (GN)? How does this look on EM/where is it located?
Group A, Beta-hemolytic streptococci
impetigo/pyoderma or pharyngitis
Immune complex deposition looks like subepithelial & subendothelial dense deposits (humps) and has a granular (IgG/C3b) IF
How do immune complexes cause inflammation in postinfectious GN?
What causes hypercellularity?
Because you’re brilliant and also good looking, you know that when you order an extra panel looking at immune fxn you’ll see a significant decrease in this immune cascade protein?
Immune complexes deposit in glomeruli and initiate inflammation by activiting COMPLEMENT and other proinflammatory mediators.
Proinflammatory mediators activate neutrophils and monocytes which in turn stimulate mesangial and endothelial cell proliferation. (hypercellularity - acute diffuse proliferative GN)
HYPOCOMPLEMENTEMIA
What are the structural features on EM of postinfectious GN?
Subepithelial and subendothelial dense deposits shaped like humps
Which disease is also known as dense deposit disease?
Type II Membranoproliferative GN
What are the 2 types of Membranoproliferative GN and how can you tell them apart?
Both have THICK GBM on H&E: tram-track appearance
think of them as chronic IC diseases
Granular IF due to IC deposition
Type I: Subendothelial deposits (HBV/HCV association)
Type II: Intramembranous deposits (autoantibody called C3 nephritic factor assocation)
What is the most common complication of SLE?
Characterized by widespread involvement of glomeruli and diffuse proliferation of mesangial and endothelial cells and even of epithelial cells. Depositis of IC are present on both sides of the GBM, in the mesangial areas, and inside the capillary loops.
Wire loop lesions = thickened BM of glomeruli
What is this called?
Nephritis
Diffuse proliferative GN of SLE
Immune complexes of IgA are deposited in the mesangium. They then activate the complement cascade through the alternative pathway.
Presents as episodic gross or microscopic hematura, with RBC casts, and proteinuria usually follows mucosal infections (gastroenteritis, respiratory tract)
Staining for IgA and C3 on renal biopsy
20% of pts develop renal failure after 10 years
Most often in young men (15-30 peak age of dx)
NAME that DISEASE
IgA nephropathy (Berger Disease)
Name the two Anti-GBM antibody diseases.
How are they different from each other?
1) Anti-GBM glomerulonephritis
2) Goodpasture Syndrome
Both have circulating anti-GMB antibodies against type IV collagen in the GBM.
If lungs and kidneys are both involved = Goodpasture Syndrome
Describe the lung involvement of Goodpasture syndrome.
anti-GBM antibody against Type IV Collagen is also expressed on pulmonary alveolar capillary basement membranes
These pts would have pulmonary hemorrhages and hemoptysis
These pathological hallmarks are characteristic of which glomerluopathy?
diffuse linear GBM immunostaining for IgG
90% of pts have glomerular crescents (crescentric glomerulonephritis aka acute renal failure) involving over 50% of glomeruli
How are crescents formed?
Is crescentric glomerulonephritis exclusive of the above glomerulopathy?
Goodpasture’s syndrome
Crescents are formed from the rupture of GBM and extravasation of blood and inflammatory cells into the urinary space, these structures are composed of proliferating epithelial cells and macrophages
NO, other diseases such as Wegener’s granulomatosis or polyarteristis nodosa can have crescents
Most common childhood vasculitis
Caused by vascular localization of IC containing IgA predominantly
Glomerular lesion is identical to that of IgA nephropathy
Other signs/symptoms: diffuse arthralgias, skin rash, violaceous maculopapular rash on lower torso (palpable purpura on buttocks and legs), oliguria, hematuria, usually occurs following an upper Resp tract infection
Henoch-Schonlein purpura (IgA vasculitis)!!!
SPOILER ALERT: Downton Abbey, if you plan on watching this show…avoid this question!!!!!!
You’re an avid fan of Downton Abbey, What did Sybil Branson die of?
Eclampsia!
What triad characterizes preeclampsia?
What is the difference b/w preeclampsia and eclampsia?
Hypertension, proteinuria, and edema complicating 3rd trimester of pregnancy
Eclampsia is when the above features are complicated by convulsions
