American Board of Internal Medicine (ABIM) Certification Practice Exam

How should varicella-zoster vaccine be administered to solid organ transplant patients if they are not immune?

1. At any time after transplantation

2. 4 weeks before transplantation

3. In the first month post-transplant

4. It is contraindicated

The correct answer is: 4 weeks before transplantation

The administration of the varicella-zoster vaccine to solid organ transplant patients who are not immune must be carefully timed to ensure safety and efficacy. The correct approach is to vaccinate these patients 4 weeks before transplantation. This timing allows for the development of the necessary immune response prior to the immunosuppressive therapy that is typically initiated after the transplant procedure. Vaccinating after the transplant, specifically in the first month post-transplant, is generally avoided due to the immunosuppressive medications that patients receive, which can interfere with the body’s ability to mount an effective immune response to the vaccine. Similarly, giving the vaccine at any time post-transplant, especially too soon, poses significant risks, including the potential for severe varicella infection, as the patient’s immune system is compromised. In many cases, vaccination is contraindicated during the post-transplant period due to these concerns. Therefore, the pre-transplant administration strategy is critical to afford some level of protection once the patient has undergone the transplant and is on immunosuppressive therapy.