[The effect of donor cytomegalovirus serological status on the outcome of allogeneic stem cell transplantation]

Objective: Donor cytomegalovirus (CMV) serological negative status may have an adverse effect on the outcome of allogeneic hematopoietic stem cell transplantation (allo-HSCT), while there is inadequate data for Chinese people. This study is to explore the impact of donor CMV serological status on the outcome of CMV seropositive patients receiving allo-HSCT. Methods: Our study retrospectively analyzed 16 CMV seropositive patients with hematological malignancies receiving allogeneic grafts from CMV seronegative donors (antibody IgG negative) at Peking University People's Hospital from March 2013 to March 2020, which was defined as D^-/R⁺ group. The other 64 CMV seropositive patients receiving grafts from CMV seropositive donors at the same period of time were selected as matched controls through a propensity score with 1∶4 depending on age, disease state and donor-recipient relationship (D⁺/R⁺ group). Results: Patients in D^-/R⁺ group developed CMV DNAemia later than patients in the D⁺/R⁺ group (+37 days vs. +31 days after allo-HSCT, P=0.011), but the duration of CMV DNAemia in D^-/R⁺ group was longer than that of D⁺/R⁺ group (99 days vs. 34 days, P=0.012). The rate of CMV reactivation 4 times or more in D^-/R⁺ group was 4/16, significantly higher than that of D⁺/R⁺ group (4.7%, 3/64, P=0.01). The incidences of refractory CMV DNAemia (14/16 vs. 56.3%, P=0.021) and CMV disease (4/16 vs. 4.7%, P=0.01) in D^-/R⁺ group were both higher than those in D⁺/R⁺ group. In addition, the application of CMV-CTL as the second-line antiviral treatment in D^-/R⁺ group was more than that in D⁺/R⁺ group. Univariate analysis and multivariate analysis suggested that CMV serological negativity is an independent risk factor for refractory CMV DNAemia and the duration of CMV infection. The cumulative incidence of aGVHDⅡ-Ⅳ, cGVHD, 3-year probability of NRM, overall survival, and the cumulative incidence of relapse were all comparable in two groups. Conclusions: Although there is no significant effect on OS and NRM, the incidence of refractory CMV DNAemia, the frequency of virus reactivation, and the development of CMV disease in D^-/R⁺ group are higher than those in controls. Therefore, CMV seropositive donors are preferred for CMV seropositive patients.