Transplant Flashcards
ABO blood compatibility is necessary for all transplants except?
liver
Which HLA are most important for compatibility?
HLA A
HLA B
HLA DR (most important overall)
Hyperacute rejection
result of preformed anti-HLA antibodies that bind the allograft endothelium leading to vascular thrombosis and ischemic necrosis
Remove allograft immediately
accelerated rejection
sensitized T cells that produce a secondary immune response
usually within 1 week of transplant
treat with pulse steroids and muromonab-CD3 (OKT3)
acute cellular rejection
cell mediated and involves T lymphocytes (cytotoxic and helper)
usually at 1 week to 1 month after transplant
treat with high dose methylprednisolone
or
treat with anti lymphocyte preparation
Chronic rejection
fibrotic process mediated by T and B cells
weeks to years after transplant
suggest humeral immune response
treat w/plasmapharesis, IVIG, rituximab to treat antibody mediated rejection
immunosuppression therapy usually has
a calcineurin inhibitor
anti proliferative agent
steroids
corticosteroids
dampen immune response by preventing lymphocytes from proliferating and neutrophils from migrating
anti proliferative agent/anti metabolite
azathrioprine
mycophenolic acid
azathioprine
purine analog that alters DNA and RNA synthesis inhibiting T and B lymphocyte proliferation
used for maintenance therapy
mycophenolate (Cell cept)
selectively inhibits lymphocyte proliferation and suppresses T and B lymphocytes
maintenance therapy
Calcineurin inhibitors
cyclosporine
tacrolimus
mTOR inhibitors
sirolimus
everolimus
cyclosporine
inhibits IL-2 production preventing initiation of T cell proliferation
maintenance therapy
tacrolimus
10-100 times stronger than cyclosporine
inhibits IL-2
maintenance therapy
sirolimus
anti-T cell agent that inhibits mTOR molecule
blocks T cell signal transduction
maintenance therapy
everolimus
mechanism and toxicity similar to sirolimus but with great bioavailability
maintenance therapy
CMV
can happen at any time but MC 1-4 months post transplant in the absence of prophylaxis
dx CMV by
peripheral blood PCR or serologic assays
tx of CMV
decreasing immunosuppression
ganciclovir (inhibits DNA synthesis)
EBV
can infect B cells at any time after transplant and can be associated with developing PTLD (type of lymphoma usually of monoclonal B cell origin)
dx of EBV
physical exam
EBV serology
CT head/chest/abdomen to look for lymph nodes, biopsy
tx of EBV
reducing or withdrawing immunosuppression
HSV
for renal transplant patients if not on ganciclovir, are given ppl dose of acyclovir
active infections treated with decreasing immunosuppression and acyclovir
BK virus
member or polyoma virus family
about 90% are seropositive
develops in 30% of kidney transplant
persistent viremia leads to BK nephropathy which occurs in 10% of transplants in first year
no effective tx
oral candidiasis
prevented or tx with oral nystatin or fluconazole
esophageal candidiasis
treated w/short course of IV amphotericin B or fluconazole
serious fungal infections
tx with amphotericin B
can also consider capsofungin and anidulafungin (less nephrotoxic)
cancers that arise in transplant patients at higher frequencies
squamous cell carcinoma basal cell carcinoma kaposi sarcoma lymphomas hepatobiliary carcinoma cervical carcinoma
Liver allocation is based on
MELD score which predicts 3 month mortality in patients with liver disease
given to patients with the highest MELD score
MELD score includes
bilirubin
creatinine
INR
ranges from 6-40
brain death
absence of pupillary, corneal, vestibule-ocular, and gag reflexes
can also do blood flow scan, arteriography, apnea test
cold ischemia time for livers
less than 6 hours
cold ischemia time for kidneys
less than 24 hours
donor livers can be preserved up to
12 hours
donor kidneys can be preserved up to
40 hours
Early poor function of transplanted kidney
reversible ATN
must get renal doppler U/S of tech 99 scan to show good vascular patency
lymphocele
lymphatic leak into retroperitoneum after kidney transplant
occur 1-2 weeks after
Dx with U/S
Tx symptomatic lymphocytes with drainage into peritoneum via lap or open
renal artery/vein thrombosis
occur first 1-3 days after transplant
if transplant kidneys works then stops all of the sudden suspect thrombosis
rapid rise in Cr, graft swelling, local pain
Dx with tech 99 renal scan or doppler U/S
must repair immediately or graft will be lost and transplant nephrectomy will be needed
urine leak
anastomotic leak or ureteral sloughing secondary to ureteral blood supply disruption
pain, increase Cr, possibly urine draining from the wound
get renal scan showing radioisotope outside the urinary tract
treat with foley to reduce intravesical pressure and subsequent surgical exploration
kidney rejection
inversely correlated with degree of HLA matching
treat with pulse steroids
cyclosporin is associated with
gallstone formation (tacrolimus too)
hirsutism
gingival hyperplasia
thrombocytopenia
which meds are associated with diarrhea, anemia, leukopenia, and neutropenia?
mycophenolate and azathioprine
impaired wound healing, thrombocytopenia, mouth ulcers, delayed graft function, interstitial lung disease
mTOR inhibitor (sirolimus and everolimus)
MCC of OPSI
pneumococcus (even if had vaccine)
biliary strictures
late hepatic artery thrombosis
initially treat non op but retransplant is typically needed eventually to avoid infectious complications
MC incision used for liver transplant
bilateral subcostal incision with midline extension to xiphoid process
MC methods used for recipient hepatectomy during orthotropic liver transplant
bicaval technique
piggyback technique
cavocavostomy (side to side caval technique)
benefit of cavocavostomy anastomosis with liver transplant
shorter vena caval clamping time
minimal changes to HD as the clamp is placed longitudinally
only clamping anterior third of vena cava up to 1/2 lumen, lower incidence of caval stenosis
lower risk for hepatic vein outflow complications d/t larger anastomosis
benefit of piggbag method for liver transplant
requires single vena caval anastomosis which limits warm ischemic time
Treatment for post transplant lymphoproliferative disorder
rituximab monoclonal antibody to CD20
leads to complement and antibody mediated B cell death
absolute contraindications for liver transplant
recent intracranial hemorrhage
elevated intracranial pressures
active substance or alcohol abuse
current or recent extra hepatic malignancy
uncontrolled sepsis
inadequate social and financial support
prohibitive cardiopulmonary disease including right heart failure
cardiac allograft rejection commonly presents
asymptomatically
Dx with perc biopsy
steroids are main treatment
