Renal

Question 1

Timeframe of hyper acute transplant rejection reactions

Answer 1

minutes to hours

Question 2

Timeframe of acute transplant rejection reactions

Answer 2

usually < 6 months

Question 3

Timeframe of chronic transplant rejection reactions

Answer 3

> 6 months to years

Question 4

Hyperacute transplant rejection reactions

Answer 4

preformed recipient antibodies against graft antigens

Morphology:
-gross mottling and cyanosis
-arterial fibrinoid necrosis and capillary thrombotic occlusion

Question 5

Acute Transplant rejection reactions

Answer 5

exposure to donor antigens induces activation of naive immune cells

predominantly cell-mediated

Morphology: cellular and humoral

Question 6

Cellular acute transplant rejection reaction morphology

Answer 6

lymphocytic interstitial infiltrate and endothelitis

Question 7

Humoral acute transplant rejection reaction morphology

Answer 7

C4d deposition, neutrophilic infiltrate, necrotizing vasculitis

Question 8

chronic transplant rejection reactions

Answer 8

chronic low-grade immune response refractory to immunosuppression

mixed cell-mediated and humoral (antibody mediated)

morphology:
-vascular wall thickening and luminal narrowing
-interstitial fibrosis and parenchymal atrophy