A MATCHED-PAIR ANALYSIS OF INFECTIONS AND RELATED MORTALITY IN HAPLOIDENTICAL VS HLA IDENTICAL TRANSPLANTATION

Introduction: Aim of this study was to evaluate the incidence of infections and the related mortality in a group of patients who underwent an unmanipulated G-CSF-primed bone marrow transplantation from an haploidentical family donor (Haplo) compared to patients undergoing transplantation from HLA-identical sibling (ID-SIB). Materials (or patients) and Methods: We analyzed 2 groups of patients (58 Haplo and 58 ID-SIB) matched for demographic characteristics, underlying disease, conditioning regimen (myeloablative conditioning-MAC or reduced intensity conditioning-RIC) and disease status (early or advanced) at transplant. All patients were conditioned with an identical regimen consisting of the Thiotepa, Fludarabine and i.v. Busulphan combination and an identical antimicrobial prevention and monitoring. The data regarding infectious episodes and related mortality during the fi rst year after transplantation were retrospectively collected from the patients’ medical records. Results: Over 1 year of observation, the number of febrile episodes and documented infections were, respectively, 297 and 270 in the Haplo group and 209 and 178 in ID-SIB group (Table). At 1 year, the cumulative incidence of infection related mortality (IRM) was, respectively, 17% in ID-SIB and 31% in Haplo (p=ns), while the probability of overall survival (OS) was 63% and 50% (p=ns) in ID-SIB and Haplo, respectively. By analyzing the subgroups of our patient series, 1-year IRM was higher in Haplo MAC respect to Haplo RIC (33% vs 15%; p=0.07) and in Haplo either transplanted in early or advanced phase (early: 20% vs 6%, p=ns; advanced: 48% vs 35%, p=ns). Discussion: Haplo had higher incidence of febrile and infectious episodes and experienced a signifi cant higher incidence of haemorrhagic cystitis. Haplo had a higher IRM, which could justify the lower 1-year OS in Haplo with respect to ID-SIB.