Infection Prevention and Management in Transplant Recipients Flashcards

Which prophylactic medication is routinely prescribed to prevent Pneumocystis jirovecii pneumonia (PCP) in solid organ transplant recipients?

Answer: Trimethoprim-sulfamethoxazole (TMP-SMX)

TMP-SMX (Bactrim) is the first-line prophylactic agent for PCP in immunocompromised transplant patients due to its proven efficacy and broad coverage.

In a CMV donor-positive/recipient-negative (D+/R-) transplant scenario, what is the recommended management strategy?

Answer: Universal prophylaxis with valganciclovir for 3–6 months

D+/R- is the highest-risk CMV serostatus combination, requiring universal antiviral prophylaxis (valganciclovir) for 3–6 months post-transplant to prevent primary CMV disease.

Which live vaccines are contraindicated in solid organ transplant recipients on maintenance immunosuppression?

Answer: MMR (measles-mumps-rubella) and varicella zoster live vaccine

Live attenuated vaccines such as MMR and live varicella zoster vaccine carry the risk of vaccine-strain infection in immunocompromised patients and are contraindicated post-transplant.

BK polyomavirus nephropathy is a significant concern primarily in which type of solid organ transplant recipient?

Answer: Kidney transplant recipients

BK virus predominantly replicates in the urothelium and tubular epithelium, making kidney transplant recipients the population most at risk for BK nephropathy and graft loss.

A transplant recipient presents with fever, productive cough, and CT findings showing bilateral ground-glass opacities three months post-transplant. Which organism should be highest on the differential?

Answer: Pneumocystis jirovecii

Ground-glass opacities on CT combined with fever and cough in the 1–6 month post-transplant window are classic for PCP, especially if prophylaxis was discontinued or inadequate.

What is the primary mechanism by which trimethoprim-sulfamethoxazole provides prophylaxis against Toxoplasma gondii in transplant recipients?

Answer: It inhibits folate synthesis, which is essential for Toxoplasma replication

TMP-SMX inhibits dihydrofolate reductase and dihydropteroate synthase, blocking folate synthesis required for Toxoplasma DNA replication, providing concurrent PCP and toxoplasma prophylaxis.

During the first month post-transplant, which category of infections predominates and reflects the patient's pre-transplant health status and surgical complications?

Answer: Donor-derived and recipient pre-existing infections, plus surgical-site and nosocomial infections

In the first month post-transplant, infections are similar to those in any post-surgical patient and reflect pre-existing conditions, donor-derived pathogens, and hospital-acquired organisms rather than immunosuppression-driven opportunists.