American Board of Surgery Qualifying Exam (ABS QE) Practice Test

What is the current maintenance regimen for transplant immunosuppression?

1. Azathioprine, prednisone, and mycophenolate mofetil

2. Cyclophosphamide, FK506, and steroids

3. FK506, MMF, and prednisone

4. Sirolimus, tacrolimus, and mycophenolate mofetil

The correct answer is: FK506, MMF, and prednisone

The current maintenance regimen for transplant immunosuppression typically involves a combination of tacrolimus (FK506), mycophenolate mofetil (MMF), and prednisone. This regimen is preferred due to its efficacy in preventing rejection while allowing for a lower risk of toxicity compared to older agents. Tacrolimus is a calcineurin inhibitor that acts by inhibiting T-cell activation, thereby reducing the immune response against the transplanted organ. Mycophenolate mofetil is an antimetabolite that selectively inhibits lymphocyte proliferation, further helping to prevent rejection. Prednisone is a corticosteroid that provides additional immunosuppressive effects, particularly during the initial post-transplant period when the risk of acute rejection is highest. Together, these three agents work synergistically to improve graft survival and reduce the incidence of rejection compared to regimens utilizing different medications. Other combinations listed may not align as closely with current practice. Some older regimens might have included azathioprine or cyclophosphamide, but they are generally considered less effective or more toxic in contemporary transplant protocols. Sirolimus is sometimes used in certain cases, but it is generally not a part of the standard maintenance regimen with tacrolimus and MMF for most transplant patients