Renal Pathology Flashcards
Pre Renal AKI Diagnostic criteria
• 0.3 mg/dL rise in creatinine over 48-hour period and/or • ≥1.5 times the baseline value within the 7 previous days
Renal blood supply compromised by 2 things
• Renal artery stenosis • Renal vein thrombosis/stenosis
Causes of Renal Artery Stenosis (FASAN()
– Fibromuscular Dysplasia (younger pts) _ Atherosclerosis (elderly pts) MOST COMMON – Scerloderma Renal Crisis (SRC) – Angiomyolipoma – Nephrosclerosis
Most common cause of Renal artery stenosis is
Atherosclerosis
Most common layer affected in Fibromuscular dysplasia
MEDIAL layer
Fibromuscular Dysplasia : What do you see?
Alternating pattern of stenosis and aneurysms causes “string of beads” appearance:
Most common cause of contribute to development of Fibromuscular Dysplasia
– Genetic
Complications of Fibromuscular Dysplasia
• Weakened wall predisposes to renal artery dissection • Renal emboli of thrombus formed in aneurysms
Treatment of Fibromuscular Dysplasia
– Angioplasty, usually without stent placement – Ex vivo reconstruction in complex cases with RA branches affected
Scleroderma Renal Crisis (SRC) is an
uncontrolled accumulation of collagen & widespread vascular lesions
Scleroderma Renal Crisis (SRC) causes
Causes thickening of the vascular wall and narrowing of lumen
Scleroderma there is
• intimal thickening of the interlobular & arcuate arteries
What comes after interlobar arteries
Afferent
Scleroderma Renal Crisis (SRC) Pathophysiology
• Endothelial injury and oxidative stress lead to ↑ fibroblast activity
SRC and renin
Causes arterial stenosis and hyperplasia of juxtaglomerular apparatus = ↑ renin production
SRC there is regulation?
• Up-regulation of endothelin-1 receptors leads to vasospasm and cortical ischemia resulting in additional renin production
Just before the afferent are the
INTERLOBULAR
SRC outcome is that
rapidly progresses to oliguric renal failure, commonly in the absence of previous signs of renal disease.
Risk factors for developing SRC: (GPR)
– Genetic (African Americans have↑ risk) – Presence of a progressive skin disease – Recent high dose corticosteroids (60% of SRC cases)
Treatment of SRC meds
Tx: – ACEi – Ca++ channel blockers – Dialysis – Renal transplant
Nephrosclerosis 2 types
Benign and MALIGNANT
Benign nephrosclerosis Occurs with _____
essential HTN or DM • Renal function minimally affected or proceeds to chronic kidney injury slowly.
Malignant Nephrosclerosis a.k.a Process ________(fast or slow)
• a.k.a. “Hypertensive Nephrosclerosis” • Process occurs very quickly
What happens to vessels in Malignant Nephrosclerosis?
• Vessel walls lose elastic fibers, become fragile, rupture easily
For Nephrosclerosis, what is seen and what are they secondary to ?
Pinpoint hemorrhages seen throughout kidney • 2o to malignant HTN (ex. 180/120 mmHg)
Renal Vein Thrombosis has same risk factors as
as DVT (Virchow’s Triad
RVT is associated with
Renal Vein Entrapment Syndrome
Most commonly affected populations for RVT
New born infants with dehydration Adults with nephrotic syndrome
Signs/Symptoms of RVT
may be asymptomatic, or have flank or low back pain if acute thrombus
Tx of RVT
anticoagulation, surgical thrombectomy
Renal Vein Entrapment Syndrome
• Renal vein stenosis - Vascular compression disorder resulting in renal venous HTN
In renal vein entrapment
Compression of the Left renal vein between the Superior Mesenteric Artery & Abdominal Aorta
Renal Vein Entrapment Syndrome • a.k.a. “
nutcracker syndrome” due to similarity of vessel position to a nutcracker:
3 parts involved in Renal vein entrapment syndrome
– Aorta – Superior Mesenteric Artery – Renal Vein
Renal Vein Entrapment Signs/Symptoms – Left gonadal vein forms anastomosis with L. renal vein
Left gonadal vein forms anastomosis with L. renal vein
What is hepatorenal syndrome
Hepatorenal Syndrome • Liver ds. causes hypotension = ↓ renal perfusion, ↓GFR and oliguria. Kidney secretes more renin
In Hepatorenal syndrome
Diseased liver fails to remove excess angiotensin & vasopressin which travel to kidneys causing ↑↑↑vasoconstriction resulting in kidney failure. (positive feedback loop)
2 types of Hepatorenal Syndrome
• Type I, and Type II Two types:
Types I hepatorenal syndrome (CAO)
• Type I – acute renal decompensation – Creatinine >2.5 mg/dL – Often fatal
Type II Hepatorenal syndrome (GCC)
• Type II – chronic renal decompensation. – Creatinine >1.5 mg/dL – GFR <40 ml/min.
Hepatorenal Syndrome Treatment (MAL)
– Manage fluid & electrolytes, bleeding, infections, and encephalopathy – Administer systemic vasoconstrictors (α-adrenergic agonists and terlipressin) and albumin – Liver transplantation (and kidney in some cases)
Other Prerenal Causes NSAIDS
NSAIDs: inhibit COX = ↓ levels of PGE2 and prostacyclins. In patients with marked volume depletion = excessive vasoconstriction (afferents)
Other Prerenal Causes CARDIO RENAL
Cardiorenal Syndrome => decompensated HF => ↓ C.O. => ↓ renal perfusion pressure leads to progressive renal dysfunction/failure.
Sepsis prerenal causes
Sepsis: LPS (liposaccharides) endotoxin causes ↑ in NO = widespread vasodilation and shock. ↑ Renin = excessive vasoconstriction
Hypovolemia causes of Pre-renal (GHDDO)
Hypovolemia • GI losses • Hemorhhage • Dehydration • Diuretics • Osmotic diuresis
Angiomyolipoma composes of _____, ____ and ______
Composed of blood vessels, smooth mscle & fat cells
• Most common benign kidney tumor
Angiomyolipoma
Angiomyolipoma associated with
Tuberous Sclerosis
In Angiomyolipoma, mass can
Mass can compress kidney or vessels can rupture
Identify all Label parts
A- Arcuate
B- Interlobular
C- Interlobar
D- Renal Artery
E- Inferior Segmental Artery
F- Ureteric branch of the renal artery
Identify kidney issue as benign or malignant
Identify issues as benign or malignant Nephrosclerosis
Identify condition in picture
Fibromuscular Dysplasia
