To define the incidence and spectrum of pulmonary complications following autologous bone marrow transplantation (BMT), we retrospectively reviewed the course of 77 consecutive patients with Hodgkin's disease (HD) and non-Hodgkin's lymphoma (NHL) who failed conventional therapy and underwent autologous BMT. Forty-five percent of the 77 patients developed respiratory complications with a mortality from pulmonary causes of 26%. A total of 38 episodes of respiratory compromise occurred in 35 patients. Infections accounted for 15 episodes (39%) and included bacterial (16%), Aspergillus (8%) cytomegalovirus (8%), Herpes simplex (3%), and other (5%) pneumonias. The spectrum of infections was similar to that reported following allogeneic BMT, but cytomegalovirus pneumonia was not as frequent a problem in those with autologous transplant. Mortality from pulmonary infections was 33%. Noninfectious disorders accounted for 23 episodes (61%) and included recurrent HD (18%), radiation/drug toxicity (16%), and acute respiratory failure thought secondary to pulmonary alveolar hemorrhage (26%). This latter entity developed acutely within 2 wk following BMT and was associated with use of thoracic radiation for treatment of malignant disease in the chest just prior to BMT (p < 0.05). It was not associated with the age of the patient or presence of thrombocytopenia, coagulopathy, renal insufficiency or neutropenia (p NS). Mortality from noninfectious causes was 65%, but in those with pulmonary hemorrhage it was 100%. In conclusion, pulmonary complications are a major source of morbidity and mortality in patients with HD and NHL undergoing autologous BMT.(ABSTRACT TRUNCATED AT 250 WORDS)