PATH RENAL Flashcards
RBC cast indicate
Glomerulonephritis, hypertensive emergency
WBC cast indicate
Tubulointerstitial inflammation, acute pyelonephritis and transplant rejection
Granular cast indicate
Acute tubular necrosis- muddy brown appearance
Fatty cast indicate “ oval fat bodies”
Nephrotic syndrome- Associated with Maltase cross” sign
Waxy cast indicate
End stage renal disease/ chronic kidney disease
Hyaline cast indicate
Can be normal
What is thrombotic thrombocytopenic purpura (TTP)?
A condition characterized by deficiency of ADAMTS13, leading to platelet aggregation triggered by accumulation of large multimers of vWF.
TTP can be inherited or acquired.
What triggers platelet aggregation in TTP?
Accumulation of large multimers of vWF.
vWF stands for von Willebrand Factor.
What are the key clinical features (C/F) of TTP?
PENTAD:
* Neurologic symptoms
* Fever
* Thrombocytopenia
* Hemolysis (microangiopathic hemolytic anemia)
* Kidney failure
The mnemonic for remembering these features is ‘nasty fever torched his kidneys’.
What does the term ‘thrombocytopenia’ refer to?
A condition characterized by low platelet count.
What type of anemia is associated with TTP?
Microangiopathic hemolytic anemia.
What is a common renal complication in TTP?
Kidney failure, cortical necrosis, and sub-capsular petechia.
What is the characteristic appearance of the basement membrane in TTP?
Double contour or tramtrack appearance.
What metalloprotease is deficient in TTP?
ADAMTS13.
What happens to ‘ultralarge’ TTP multimers in the presence of ADAMTS13?
They are normal and not degraded.
Ultralarge multimers of vWF are typically associated with increased platelet aggregation.
Where are microthrombi found in TTP?
In glomerular and interstitial capillaries.
What is diffuse cortical necrosis?
A complication seen in TTP characterized by widespread death of kidney cortex tissue.
What is the typical form of hemolytic uremic syndrome (HUS) associated with?
Diarrhea-positive Escherichia coli strain 0157:H7 intestinal infection
Typical HUS is also known as epidemic or classic HUS.
What toxin does the typical HUS strain elaborate?
Shiga-like toxin (stx)
This toxin is responsible for the pathogenesis of typical HUS.
What receptor does Stx bind to in the pathogenesis of typical HUS?
Globotriasylceramide GB3 receptor
This receptor is primarily found on the renal endothelium.
What are the consequences of Stx binding to the GB3 receptor?
- Damage to the endothelium
- Platelet activation and vasoconstriction
- Formation of microthrombi
- Vascular obstruction & tissue ischemia
- Shearing of RBCs
- Schistocytes and thrombocytopenia
These processes contribute to the symptoms observed in HUS.
What characteristic appearance is associated with the basement membrane in HUS?
Rouble contour or tramtrack appearance
This appearance is noted in the context of endothelial damage.
What defines atypical HUS?
Non-epidemic, diarrhea-negative
Atypical HUS has different underlying mechanisms compared to typical HUS.
