transplant Flashcards
In which kinds of transplants is HLA antigen matching more (or less) important?
- more important for kidney and pancreas
- less important for heart and liver
What are risk factors for graft vs. host disease?
HLA antigen mismatch, old age, donor-host gender disparity, immunosuppression
What are the manifestations of graft vs host disease? Lab/biopsy findings?
rash (maculopapular), abd pain, N/V, diarrhea, recurrent infection, bleeds
labs: elevated LFTs, decr. immunoglobulin levels, decr. platelets. biopsy shows inflammation w/ significant cell death
What are treatment options for graft vs host disease?
steroids, tacrolimus, mycophenolate acutely; may give thalidomide and hydroxychloroquine in chronic disease
What are complications of graft vs host disease?
chronic disease: skin sclerosis, hepatic insufficiency, GI ulcers, pulm fibrosis
What is an acute transplant rejection?
6 days to 1 yr post transplant due to antidonor T-cell proliferation in recipient (occasionally due to development of antibodies after transplant). biopsy shows hypercellular lymphocytic infiltrate. often reversible with immunosuppressive agents
What is chronic transplant rejection?
months to yrs after transplant, the patient develops multiple cellular and humoral immune rxns to donor tissue
What are the organ specific types of chronic transplant rejection?
heart- atherosclerosis
lungs- bronchiolitis obliterans
liver- vanishing bile ducts
kidney- vascular fibrosis, glomerulopathy
How does cyclosporine work? side effects?
calcineurin inhibitor that binds cyclophilin and blocks T cell activation by preventing IL-2 transcription. This blocks helper T-cell function. However, it can cause nephrotoxicity, androgenic effects, and HTN
How does tacrolimus work? side effects?
calcineurin inhibitor that binds FK506 binding protein and blocks T cell activation by preventing IL-2 transcription.
nephrotoxic, neurotoxic
How does azathioprine work? side effects?
antimetabolite precursor of 6-mercaptopurine that prevents lymphocyte production by blocking neucleotide synthesis. causes leukopenia; toxicity increased by allopurinol
What is rapamycin/sirolimus?
mTOR inhibitor that prevents IL-2 signal transduction through a different pathway (ie not a calcineurin inhibitor like cyclosporine or tacrolimus), so it is NOT nephrotoxic. may cause thrombocytopenia or hyperlipidemia
mycophenolic acid
prevents rejection by inhibition of T cell proliferation, but can cause leukopenia, GI toxicity
When is a pancreas transplant indicated? contraindicated?
DM1 with renal failure. not done if age >60, CAD, PVD, obesity, DM2.
What are the indications for lung transplant?
COPD, esp if related to alpha 1 antitrypsin deficiency, primary pulmonary HTN, CF, estimated death within 2 yrs. Not done if smoking in past 6 mo, poor function of heart, liver, or kidnies, age >65, HIV
chronic rejection is common, and there is about a 50% 3 yr survival rate
