Week 6 Flashcards
If you suspect nephritic syndrome → check C3/C4 levels
- What are some differentials for low levels? (what causes these low levels?)
- what are some differentials for normal levels?
- Glomerulonephritis, cryoglobulinemia, SLE, membranoproliferative → All the differentials on low category activate complement which means C3/C4 are used up and result in low levels when analyzing patient samples
- Vasculitis, anti-GBM antibodies
- Proteinuria: which lab value is common for glomerular disease?
- Nephritic syndrome - which filtration barriers were lost (RBC,protein)
- Nephrotic syndrome - which filtration barriers were lost (RBC,protein)
- 4+
- both (but affects RBC filtration barrier more)
- Just the protein filtration barrier
Nephrotic syndrome
- what is the damage in this syndrome?
- clinical presentation (2)
- urinary findings? (3)
- podocyte damage → leads to impaired charge barrier which is supposed to prevent albumin from coming into nephron
- ankle and periorbital swelling, hypercholesteremia
- frothy urine, proteinuria, oval fat bodies (lipids trapped in casts → maltese cross)
Nephritic syndrome
- what is the damage in this syndrome?
- clinical presentation (3)
- urinary findings? (3)
- glomerular inflammation leads to basement membrane damage (damage to endothelial and mesangial cells) → this leads to hematuria
- dark urine, swelling, fatigue
- hematuria, RBC casts, proteinuria (<3.5 g/day)
- How does Nephrotic Syndrome lead to increased risk of infection?
How does Nephrotic Syndrome lead to thrombosis?
How does Nephrotic Syndrome lead to increased hyperlipidemia?
- Hyperlipidemia is common in patients with the nephrotic syndrome. The main cause is probably increased hepatic lipogenesis
How does Nephrotic Syndrome lead to edema?
Loss of the proteins from your blood allows fluid to leak out of the blood vessels into the nearby tissues causing swelling.
- How does nephritic syndrome lead to Hypertension
- How does nephritic syndrome lead to Edema
- This causes a decrease in glomerular filtration rate (GFR) and, if left untreated over time, will eventually produce uremic symptoms and retention of sodium and water in the body (to increase volume → increase GFR), leading to both edema and hypertension.
- the bit of proteinuria can still lead to edema
POST-STREP GLOMERULONEPHRITIS (PSGN)
- nephritic or nephrotic?
- Pathology?
- Presentation (5)
- nephritic
- (Type 3 HSR) Immune complexes deposit in glomerulus and attract neutrophils → this leads to inflammation and destruction in epithelial and mesangial cells (glomerulus)
- seen in children after GAS infeciton of pharynx/skin. + peripheral and periorbital edema + cola colored urine + HTN + Hypocomplementemia (low C3/C4)
POST-STREP GLOMERULONEPHRITIS (PSGN)
- Histology (which of these images)?
- enlarged, hypercellular glomerulI
POST-STREP GLOMERULONEPHRITIS (PSGN)
- Immunofluorescence - type of appearance (granular/linear)?
- does it stain positive for any abs?
- granular
- stains positive for IgG, IgM, C3
POST-STREP GLOMERULONEPHRITIS (PSGN)
- Electron microscopy- any special structures?
subepithelial humps - showing where immune complexes get deposited and cause effect.
BERGER’S DISEASE/IgA NEPHROPATHY
- nephritic or nephrotic?
- Pathology?
- Presentation
- Nephritic
- increased IgA synthesis → makes IgA immune complex that deposit in the mesangium → this leads to inflammation/damage since this is a type III HSR
- repeated episodes of hematuria following days after respiratory/GI tract infections (days is a good indicated it is this bc PSGN takes weeks)
BERGER’S DISEASE/IgA NEPHROPATHY
- histology
- electron microscopy
- immunofluorescence
- mesangial proliferation (also seen on electron microscopy)
- granular appearance with stains positive for IgA
DIFFUSE PROLIFERATIVE GLOMERULONEPHRITIS (DPGN)
- nephritic or nephrotic?
- Pathology?
- Presentation
- nephritic
- complication of SLE (lupus) - known as type IV lupus nephritis - subendothelial immune complex deposits (which include anti-dsDNA) in glomeruli and drives immune response via type III HSR
- more than 50% of glomeruli are affected (hence diffuse…focal is <50%) _ SLE features like rash, arthritis, etc
DIFFUSE PROLIFERATIVE GLOMERULONEPHRITIS (DPGN)
- Histology structures
- Immunofluorescence
- “wire looping” of capillaries - looks like thickened, dark purple capillaries
- granular appearance - “FULL HOUSE” staining (IgG, IgA, IgM, C3, C1q)
RAPIDLY PROGRESSIVE (CRESCENTERIC) GLOMERULONEPHRITIS (RPGN)
- nephritic or nephrotic?
- Pathology?
- Presentation
- Nephritic
- This is more of a pathologic description because many diseases (including acute renal failure) can lead to this condition. It is a severe form of glomerulonephritis.
- rapid onset, fatigue, anorexia
RAPIDLY PROGRESSIVE (CRESCENTERIC) GLOMERULONEPHRITIS (RPGN)
- histology
- shows crescents formed by inflammation of macrophages and also fibrin
RAPIDLY PROGRESSIVE (CRESCENTERIC) GLOMERULONEPHRITIS (RPGN)
- Differentiate between Type I, II, and IV in terms of immunofluorescence
- Type I RPGN - linear IF / anti-basement membrane Abs (type II HSR)
- Type II RPGN: granular IF / immune complex deposition (type III HSR)
- Type IV RPGN: negative IF / pauci-immune (ANCA positive)
RAPIDLY PROGRESSIVE (CRESCENTERIC) GLOMERULONEPHRITIS (RPGN)
- What diseases are associated with Type I, II, and III RPGN?
- Type I - Goodpasture’s (rare disorder in which your body mistakenly makes antibodies that attack the lungs and kidneys)
- Type II - most commonly results as a progression of PSGN and DPGN/SLE
- Type III - vasculitis syndrome
Alport Syndrome
- Nephritic or Nephrotic?
- Pathology
- Presentation
- nephritic- this is genetic (x-linked)
- mutations lead to defect in collagen type IV → this is found in basement membrane of kidney, eye, ear
- Hematuria, hearing loss, occular disturbances (look for triad and family history)
MINIMAL CHANGE OF DISEASE
- Nephritic or Nephrotic?
- Pathology
- Presentation
- tx?
- Nephrotic
- effacement/thinning of foot process leads to loss of negative charge barrier. The damage to the podocyte is cytokine induced (common in children after infection)
- selective proteinuria - only albumin will appear in urine
- Favorable prognosis and Responds well to steroids
MINIMAL CHANGE OF DISEASE
- histology
- Immunofluorescence
- electron microscopy
- normal
- normal
- can see slight podocyte foot process efacement
FOCAL SEGMENTAL GLOMERULOSCLEROSIS (FSGS)
- Nephritic or Nephrotic?
- Pathology
- Causes and complications?
- tx?
- Nephrotic
- Hyaline collagen deposits in glomerulus which causes basement membrane to collapse + foot processes effacement
- Usually idiopathic, HIV, sickle cell, etc can be cause — can progress to chronic renal failure
- Does not respond to steroids
FOCAL SEGMENTAL GLOMERULOSCLEROSIS (FSGS)
- Histology
- Immunofluorescence
- focal, segmental sclerosis/lesions of collagen which look pink and dense
- usually negative → SOMETIMES positive for IgM, C3, C1
MEMBRANOUS GLOMERULONEPHRITIS/NEPHROPATHY
- Nephritic or Nephrotic?
- Pathology
- Causes?
- Nephrotic
- Immune complexes deposit on subepithelial region between podocyte and basement membrane → this disrupts filtration barrier and then podocytes lay down extra BM which leads to thickened glomerular BM
- idiopathic (anti-phospholipase A2 Abs), SLE, tumors, HBV+HCV, etc
MEMBRANOUS GLOMERULONEPHRITIS/NEPHROPATHY
- histology
- immunofluorescence
- electron microscopy
- thickened GBM with absence of hypercellularity
- granular appearance (stains positive for IgG and C3)
- shows dense deposits and spike and dome appearance
DIABETIC GLOMERULONEPHROPATHY
- nephritic or nephrotic?
- pathology
- histology
- nephrotic
- non-enzymatic glycosylation of GBM → leads to mesangial expansion and leakage of proteins
- mesangial expansion, GBM thickening, Kimmelsteil Wilson lesions (eosinophilic - Nodules of pink hyaline material form in regions of glomerular capillary loops in the glomerulus. This is due to a marked increase in mesangial matrix)
MEMBRANOPROLIFERATIVE GLOMERULONEPHRITIS (MPGN)
- Nephritic or nephrotic?
- pathology
- How many types?
- can cause both
- thickened GBM and proliferation of mesangial cells+mesangial matrix (all of which create a hypercellular environment - HYPERCELLULAR ENVIRONMENT IS WHAT MAKES THIS DIFFERENT THAN MEMBRANOUS NEPHROPATHY)
- Type I and II
MEMBRANOPROLIFERATIVE GLOMERULONEPHRITIS (MPGN)
Type I
- pathology
- immunofluorescence
- histology
- associated with what other diseases/disorders
- Type I MPGN: subendothelial IgG immune complex deposition → inflammation / mesangial ingrowth
- Presents with granular IF (positive for IgG / C3)
- Tram tracking- where basement membrane looks outlined twice
- associated with hepatitis B and C infection
MEMBRANOPROLIFERATIVE GLOMERULONEPHRITIS (MPGN)
Type II
- pathology
- immunofluorescence
- Electron microscopy
- electron dense deposits in basement membrane → complement overactivation
- Presents with granular IF (negative for IgG)
- dark ribbons’ on EM
Fill in the blanks
ACUTE TUBULAR NECROSIS (ATN)
- pathology
- what are the different types
- sudden damage to tubular epithelial cells due (maybe due to ischemia or drugs)
- ischemic ATN and nephrotoxic ATN
ISCHEMIC ACUTE TUBULAR NECROSIS (ATN)
- pathology
- what parts of the nephron does it affect (2)
- causes (3)
- renal ischemia due to vasoconstriction lowers GFR and can cause tubular epithelial necrosis. — There is LOSS OF TUBULAR CELL POLARITY (in which Na/K ATPase move to luminal side and excrete Na+ → further activates macular densa → leads to more vasoconstriction and ischemia/necrosis)
- proximal convoluted tubule and thick ascending limb
- hypovolemia, shock, massive bleeding
NEPHROTIC ACUTE TUBULAR NECROSIS (ATN)
- pathology
- what parts of the nephron does it affect (1)
- causes
- damage to tubular epithelial cells induced by specific substances (drug induced or toxin induced) - drugs include cisplatin, lead, contrast dye – toxins include uric acid, myoglobin (from rhabdomyolysis), ethylene glycol
- PCT only
- drug and toxin induced
ACUTE TUBULAR NECROSIS (ATN)
- What leads to the creation of granular cysts
- what does histology of ATN look like? (3)
- epithelial cells sough off into urine and create casts that look muddy brown in appearance
- patchy, focal necrosis of nephron - the lumen has occlusions due to epithelial cells sloughing off - “skip” areas of nephron (areas that are unharmed)
ACUTE TUBULAR NECROSIS (ATN)
- what are the phases of ATN (3)
- Phase I (Injury): initial injury occurs, leading to slight decline in urine output
- Phase II (Maintenance): presents with oliguria / hyperkalemia / AG metabolic acidosis / uremia
- Phase III (Recovery): presents with polyuria / hypokalemia (overactivity of kidneys)
ACUTE INTERSTITIAL (TUBULOINTERSTITIAL) NEPRHITIS
- pathology
- presentation (6)
- causes (3)
- inflammation of renal tubules/interstitium - this is due to a hypersensitivity reaction mediated by eosinophils and neutrophils (like an allergic reaction)
- fever, rash, hematuria, sterile pyuria, CVA tenderness, urinary eosinophilia
- drug induced (sulfonamides, rifampin, penicillin) , infection, systemic diseases
no evidence of nephrotic/nephritic syndrome
CHRONIC INTERSTITIAL (TUBULOINTERSTITIAL) NEPRHITIS
- how do the tubules present differently than in acute?
- how does BUN:Cr change with chronic NSAID use
- fibrosis or atrophy of the tubules
- mildly increased - symptoms resolve with cessation of NSAID use