Cytomegalovirus Infection after Unrelated Cord Blood Transplantation (CBT) for Adults with Hematological Diseases.

Backgrounds: Cytomegalovirus (CMV) infection is a major complication after allogeneic transplantation; however clinical significance of CMV reactivation after cord blood transplantation remains unclear.

Objective: We retrospectively investigated the incidence of CMV antigenemia, and CMV diseases, and its prognosis in adult patients who underwent reduced-intensity cord blood transplantation (RI-CBT)

Patients/ Methods: We reviewed medical records of 77 patients who received RICBT at Toranomon Hospital between January 2002 and March 2004. Median age of the patients was 55 years (range 17–79). Underlying diseases were chemorefractory hematologic diseases (n=76) and severe aplastic anemia (n=4). Conditioning regimen comprised fludarabine (125 mg/m²), melphalan (80 mg/m²), and TBI 4-8Gy. GVHD prophylaxis was cyclosporine (n=69) or tacrolimus (n=11). Median total nucleated cells and CD34+ cells was 2.4×10⁶ cells/kg (0.39–4.3), and 0.81×10⁵ cells/kg (0.05–5.7) respectively. HLA disparity was 6/6 (n=3), 5/6 (n=12), 4/6 (n=63), and 3/6 (n=2). All patients were monitored CMV-antigenemia weekly and received pre-emptive gancyclovir or foscarnet.

Results

CMV antigenemia tested positive in 47 patients on a median of day 32 (range, 12–55) after RICBT. The cumulative incidence of CMV reactivation at day 100 was 0.70. Seven and 29 patients were treated with preemptive ganciclovir and foscarnet, respectively. Adverse events of them were myelosuppression in 3 patients given ganciclovir, and mild hyponatremia in a patient given foscarnet. CMV diseases developed in 15 patients on a median of day 39 (range 15–92); enterocolitis (n=13), pneumonia (n=1), and encephalitis (n=1). Seven of 15 patients were resolved with antiviral treatment, and the other patients were fatal with CMV infection. Univariate analysis showed any risk factors for CMV reactivation.

Discussion

CMV reactivation and diseases develop early after cord blood transplantation. Opitimal strategy for preventing CMV disease should be established in RICBT.