Interstitial pneumonitis after BMT: 15 years experience in a single institution.

Data from 311 patients with hematological malignancies who received an autologous, allogeneic or syngeneic BMT in a single institution were analyzed. Interstitial pneumonia (IPn) was observed in 58 patients. Two years actuarial probability of IPn was 26.8%. In 50% of cases CMV was detected. In 23 patients (39.7%) IPn was considered idiopathic. The median time from BMT to IPn was 63.5 (range 7-720) days. Patients submitted to allogeneic BMT had a significantly higher risk of developing IPn than patients receiving syngeneic or autologous BMT (34.1% vs 16.7% and 4.9%, respectively; p = 0.0006). Among 230 patients receiving allogeneic transplant, factors with a higher risk for IPn in univariate analysis were: age over 20 years, CML, alloimmunized donor, previous splenectomy, acute and chronic GVHD. When the analysis was restricted to patients with a CMV-associated IPn, all factors except alloimmunization maintained their significance. Multivariate analysis showed that only acute GVHD (p < 0.0001) and a diagnosis of CML (p < 0.001) in the whole group of allogeneic transplants, and acute GVHD (p < 0.001) and splenectomy (p < 0.003) in CMV-associated IPn, maintained their significance. These results are discussed within the frame work of the clinical application of BMT.