CMV after hematopoietic stem cell transplantation

Background

Reactivation of latent recipient CMV infection is common after hematopoietic stem cell transplantation

Reactivates in 60 to 70% of CMV-seropositive patients and primary infection affects 20 to 30% of seronegative recipients who have seropositive donors

Risk is proportional to the amount of T cell dysfunction, so risk is higher earlier in disease and after fludarabine, alemtuzumab, or 2-chlorodeoxyadenose
GVHD is another important risk factor

With monitoring and preemptive therapy, CMV pneumonitis has decreased to 5% of seropositive allogeneic recipients
Pneumonitis (63%)
Enteritis (26%)
Retinitis (5%)
Increased risk of rejection

Most frequently managed with weekly viral loads and preemptive treatment (PET) at a lab-specific threshold
Antiviral treatment follows a model of induction therapy for 14 days; if it has declined by at least 1 log, then step down to lower-dose maintenance therapy until viremia resolves fully; otherwise, continue induction dosing
- Induction therapy
  - Ganciclovir 5 mg/kg q12h
  - If concerns about resistance or bone marrow suppression, foscarnet 90 mg/kg IV q12h
- Maintenance therapy
  - Valganciclovir 900 mg po daily
  - If concerns about oral absorption, continue ganciclovir 5 mg/kg IV q24h
  - If concerns about resistance or bone marrow suppression, foscarnet 90 mg/kg IV q24h
Use CMV safe (leukoreduced or filtered) blood products if the recipient is CMV seronegative

Treatment is with ganciclovir induction for 14 to 21 days with IVIG 500 mg/kg every other day, followed by maintenance ganciclovir for at least 3 to 4 weeks
May need to continue maintenance for longer if patient has GVHD, enteritis with deep ulcerations, or retinitis