Organ Transplantation Flashcards
Who is eligible as an organ donor?
-Virtually all brain-dead patients, regardless of age
What can be done with donors who have specific infections?
-Their organs can be given to a recipient with a similar infection (for example: hepatitis)
What is the general rule for physicians regarding donor eligibility?
-Potential donors are referred to harvesting teams and they will exclude the few that cannot be used at all
Which is the one absolute contraindication to organ donation?
-HIV positive status
What are the ways in which transplant rejection can happen?
- Hyperacute
- Acute
- Chronic
What is hyperacute rejection?
- Vascular thrombosis within minutes of reestablishing blood supply to the organ
- Caused by preformed antibodies
- Prevented by ABO matching and lymphocytotoxic crossmatch (Not sen clinically)
What is acute rejection?
- Occurs after first five days and usually within the first 3 months
- Episodes occur even if patient is on immunosuppressives
- Suggested by signs of organ dysfunction
- Confirmed by biopsy
What is the most common cause of liver transplant rejection?
-Technical problems (not immunologic)
What are the signs of liver transplant failure?
-Rising gamma-glutamyltransferase (GGT), alkaline phosphatase, and bilirubin
What should be done first when liver function deteriorates after a transplant?
-R/o biliary obstruction by US and vascular thrombosis by doppler
What is important to keep in mind regarding heart transplant rejection?
-Signs of functional deterioration occur too late to allow for effective therapy
-Routine ventricular biopsies (via jugular, SVC and right atrium) are done at intervals
-
What is the first line therapy for rejection?
-Steroid boluses
What other treatments are available for acute rejection if first line treatment fails?
- Antilymphocyte agents (OKT3), but have higher toxicity
- Antithymocyte serum is tolerated better
What is chronic rejection?
- Seen years after a transplant w gradual, insidious loss of organ function
- Poorly understood and irreversible
How is chronic rejection managed?
- There is no treatment
- Patients undergo biopsies in the hope that it may be a delayed and treatable case of acute rejection.