American Board of Internal Medicine (ABIM) Certification Practice Exam

In patients who have undergone solid organ transplantation, when should they receive their first dose of PPSV23?

1. Before transplantation

2. 6 months after transplantation

3. 1 year after transplantation

4. 5 years after transplantation

The correct answer is: Before transplantation

Patients who have undergone solid organ transplantation should receive their first dose of PPSV23 (Pneumococcal polysaccharide vaccine) before the transplantation occurs. This timing is crucial because transplant recipients are at higher risk for various infections, including those caused by encapsulated organisms such as Streptococcus pneumoniae. Administering the vaccine prior to transplantation helps to ensure that the patient has developed immunity against pneumococcal disease, which can significantly reduce the risk of post-transplant infections. Vaccination before transplantation can be part of a broader preoperative care plan, allowing adequate time for an immune response to develop and offering protective benefits when the patient starts immunosuppressive therapy after the transplantation. This proactive approach is essential since immune function is impaired following transplantation due to medication used to prevent organ rejection. In contrast, the timing of vaccination after transplantation is generally delayed due to the immunosuppressive therapy that patients receive, which may prevent effective immune response to the vaccine. Therefore, it is best practice to ensure that vaccination with PPSV23 occurs before the surgery.