Risk factors in interstitial pneumonitis following allogenic bone marrow transplantation.

Total body irradiation is part of the preparatory regimen for allogeneic bone marrow transplantation because of its cytotoxic and immunosuppressive properties. A major toxicity of bone marrow transplantation has been interstitial pneumonitis, which may be, in part, related to the lung irradiation. One hundred and sixty-one consecutive patients receiving allogeneic bone marrow transplantation for leukemia and aplastic anemia at Johns Hopkins Hospital (1968-1979) were retrospectively studied. The present study demonstrated that lung shielding to 600 rad maximum in single dose total body irradiation, fractionation of total body irradiation in comparison to single dose total body irradiation, and absence of graft versus host disease in the leukemia patients, each reduced the risk of interstitial pneumonitis. Total body irradiation significantly reduced the leukemia recurrence rate and/or the failure of remission induction.