American Board of Internal Medicine (ABIM) Certification Practice Exam

In what situation should intramuscular immunization for patients undergoing hematopoietic stem cell transplantation be considered?

1. If unresponsive post-transplant

2. If indications for nontransplant patients are met

3. Only based on physician discretion

4. Immunization is generally contraindicated

The correct answer is: If indications for nontransplant patients are met

For patients undergoing hematopoietic stem cell transplantation (HSCT), re-immunization is essential to restore their immune response, particularly because the transplant process can significantly impair the immune system. The primary consideration for determining when to initiate immunization revolves around whether the indications typically met for immunization among non-transplant patients are satisfied in this specific patient population. Once the patient's immune system begins to recover following HSCT—usually a few months post-transplant and often evaluated by monitoring immunoglobulin levels and lymphocyte counts—reactions similar to those in non-transplant patients become applicable. Therefore, if the clinical conditions that would necessitate immunization in the general population are present, this is the appropriate time to proceed with intramuscular immunization for these patients. In contrast, if a patient is unresponsive post-transplant, it may indicate that their immune system has not yet recovered sufficiently to mount a reaction, making this not an ideal situation for immunization. Relying solely on physician discretion may lead to inconsistencies in practice, whereas general contraindications to immunization are not applicable once the appropriate criteria for non-transplant patients are fulfilled.