Lecture 21.a - Nephritic Syndrome Flashcards
Nephritic and Nephrotic syndromes are both diseases of the ______.
Glomerulus
There is a direct relationship between ____ ____ and total glomerular number.
Birth weight
What is the normal number of mesangial cells per mesangial area and what happens to the lumenal size of the capillaries with mesangial expansion?
Normal is 3. With mesangial expansion (more than 3 per mesangial area), the lumenal space of the adjacent capillaries becomes narrowed –> impaired kidney function.
The Glomerular basement membrane (GBM) is composed of type ____ collagen. ____ syndrome is an X-linked recessive disease that affects the alpha 5 chain of this collagen. A less common disease that affects the GBM is Thin Basement Membrane disease (which is autosomal ______), caused by a mutation in the Alpha ___ or ___ chains.
Type IV collagen
Alport’s syndrome
Autosomal Dominant
Alpha 3 or 4
Podocyte effacement (flattening out of the cell with increased space between them/their interdigitations) is a hallmark of ______ (nephritic or nephrotic?) syndrome.
Nephrotic
Rapidly progressive glomerulonephritis (RPGN) is classified as a _____% decline in GFR within ____ months with ____% crescents (layers of proliferating cells in Bowman’s capsule that compress the glomerulus) on renal biopsy.
50%
3 months
50%
Glomerulonephritis is considered Focal if ____% or less of the glomeruli are affected. If it’s more than that, it’s considered Diffuse.
50% or less –> focal
What does Segmental vs Global refer to with respect to glomerulonephritis?
Segmental –> only part of any one glomerulus is affected, while the other part remains functional.
Global –> all of a single glomerulus is affected.
Which is characterized by inflammation, Nephritic or Nephrotic syndrome?
Nephritic
The most common cause of Nephritic syndrome world wide is _____ nephropathy.
IgA Nephropathy
When there is blood in the urine WITHOUT protein (at least at first), think ____ syndrome or ____ ____ ____ nephropathy. These can be distinguished from Nephritic syndrome bc with Nephritic, you WILL see proteinuria from the beginning.
Alport’s syndrome
Thin Basememnt Membrane Nephropathy
Alport’s Syndrome results in thickening of ______ in more than 50% of glomerular loops. Also look for enlarged _____ and _____ expansion.
GBM
Podocytes
Mesangial expansion
There are also Autosomal recessive (AR) and autosomal dominant (AD) forms of Alport’s Syndrome.
In the AR form, patients tend to reach ESRD in their _____ decade of life, about a decade sooner than the X-linked form. AD form –> slower progression.
3rd decade
The most common non-kidney findings in patients with Alport’s syndrome include _____ and _____ changes/loss.
Vision and Hearing changes/loss. Keep in mind visual changes are not common in the AD form.
To distinguish between Alport’s and TBMD look to ____ biopsy, which will show lack of staining of the basement membrane in 80% of Alport’s cases.
Also remember how the GBM will differ between Alport’s and TBMD…
Skin
In Alport’s –> GBM will be THICK
Anti-GBM forms of Glomerulonephritis include Anti-GBM disease and Goodpasture’s disease. How can you distinguish between the two?
Goodpasture’s will have LUNG involvement, while Anti-GBM disease is Renal limited.
Anti-GBM disease and Goodpasture’s are both categorized as Type 1 RPGNs.
How will their Immunofluorescent staining appear?
How does this compare to Type 2 (immune complex) RPGNs and Type 3 (Pauci Immune, - ANCA associated vasculitis) RPGNs?
Immunofluorescence of Type 1 –> linear outline of capillaries
Type 2 –> granular staining
Type 3 –> no staining
Presence of _______ RBCs has 98% Specificity for Glomerulonephritis. However, it only has 52% Sensitivity (negative test not reliable). Just keep in mind that only 10% of cases of Hematuria WITHOUT Proteinuria are glomerular in origin –> must rule out _____.
Dysmorphic
Cancer
What is the gold standard for diagnosis of Glomerulonephritis?
Renal Biopsy
Goodpasture’s syndrome patients have auto-antibodies against the _____ chain of Type IV collagen, which is mainly found in GBM and Alveolar basement membrane (so again, look for LUNG involvement!)
Alpha 3 chain
Post-infectious Glomerulonephritis patients typically experience AKI ____-____ days after Strep infection. Patients will present with ____ colored urine, flank pain, and histology will show _______ humps.
10-14 days
Tea-colored urine
Subepithelial humps (immune complex deposition between GBM and visceral epithelium.)
If Staph is the infectious agent in Infection-related Glomerulonephritis, when does AKI typically occur?
Typically DURING the infection, which helps distinguish it from post-strep Glomerulonephritis.
Lupus nephritis is most common in which demographics?
Young, female, and African American.
Class III and IV Lupus Nephritis are aggressive and proliferative. Which is focal, which is diffuse?
Class III –> focal
Class IV –> Diffuse
