Cytomegalovirus viremia in lung transplantation during and after prophylaxis

Lung transplantation has a high risk of cytomegalovirus (CMV) viremia and disease.

Valganciclovir was planned for 6 months in CMV recipient seropositive (R+) lung transplants (LTs) and given long-term in D+R- LTs. CMV viremia was monitored regularly during and after prophylaxis in all patients.

Of 137 LTs, 22 were D+R-, 49 D+R+, 43 D-R+, and 23 D-R-, with median follow up 4.1 years (IQR 2.1-6.2 years). CMV viremia at any time occurred in 44.5% of LTs. CMV viral load >10³  c/mL was uncommon (9/77 episodes). CMV viremia occurred at median 665 days (IQR 271-1411 days), in 5.1% LTs <6 months, 20.3% LTs 6-12 months, and 35.8% LTs >12 months. CMV disease occurred in 6 (4.4%) LTs at an overall rate of 1.0 episode per 100 person-years: two of these cases were organ-specific disease, four were CMV syndrome. One case of ganciclovir-resistant CMV was diagnosed. D+R+ and D+R- LTs had higher viremia rates than the D-R+ group. No viremia occurred in D-R- LTs. CMV viremia was not associated with age, gender, type of LT, indication for LT, acute rejection, bronchiolitis obliterans syndrome, or mortality.

Prophylaxis for 6 months in D+R+ and D-R+, and past 12 months in D+R- LTs, with long-term monitoring in all patients using a sensitive assay, and reinstitution of valganciclovir for low-level viremia was effective at markedly reducing the incidence of CMV disease. CMV D-R- LTs do not need routine CMV monitoring.