Question
Which of the following is seen in this image marked by A ?
A. Hyaline necrosis
B. Fibrinoid necrosis
C. Medial wall hyperplasia
D. Microaneurysm
Show Answer
|
Correct Answer » B Explanation |
 |
Ans. is B. Fibrinoid necrosis
This structure is kidney malignant hypertension
Malignant hypertension and accelerated nephrosclerosis
Definition / general:
- Also called hypertensive emergency, malignant nephrosclerosis.
- Malignant nephrosclerosis is the form of renal disease associated with malignant or accelerated phase of hypertension.
- Severe hypertension with acute impairment of one or more organ systems (especially CNS, cardiovascular, renal) that may cause irreversible organ damage.
Pathophysiology:
- Vascular damage (due to chronic hypertension, arteritis, coagulopathy) increases permeability of small vessels to fibrinogen and other plasma proteins.
- This causes endothelial injury and platelet deposition, which causes fibrinoid necrosis.
- Kidneys become ischemic, which stimulates renin-angiotensin system to produce angiotensin II, which causes renal vasoconstriction, as well as increased aldosterone secretion and salt retention, which elevate blood pressure even further
- May be related to increased TRPC3 expression in vascular endothelium
Gross description:
- “Flea bitten” appearance of kidney due to pinpoint petechiae on cortical surface.
- These small pinpoint petechial hemorrhages appear on the cortical surface from rupture of arterioles or glomerular capillaries.
