Polyoma viruria following T-cell-depleted allogeneic transplants using Campath-1H: incidence and outcome in relation to graft manipulation, donor type and conditioning.

Haemorrhagic cystitis (HC) is an important cause of morbidity following stem cell transplantation (SCT) and has been associated with polyoma virus infection. We studied the incidence and outcome of polyoma virus infection in 58 T-cell-depleted SCT patients. T-cell depletion was carried out using Campath-1H, either 10 or 20 mg in vitro (n=33) or 50 or 100 mg in vivo (n=25) following conventional (n=35) or nonmyeloablative conditioning (n=23). A total of 21 patients (36%) had polyoma viruria at a median of 35 days (5-114); 30% among patients receiving Campath in vitro and 44% among those given in vivo. The only risk factor for polyoma viruria was graft-versus-host disease GVHD grade >or=2. The onset of polyoma viruria coincided with Cytomegalovirus (CMV) reactivation in all six patients who reactivated both viruses. Prolonged viruria (defined as polyoma viruria >2 weeks) was documented in 10 patients (17%) and this was associated with GVHD >or=grade 2. HC occurred in four patients. Prolonged viruria was associated with HC only in patients receiving unrelated donor grafts following conventional conditioning. HC was not observed following nonmyeloablative conditioning despite a higher incidence of prolonged viruria. Thus, HC was uncommon in patients with polyoma viruria following T-cell depletion with Campath, particularly after reduced intensity conditioning.