Pneumonia in bone marrow transplant patients.

The radiographic, pathologic, and clinical features of 22 episodes of pneumonia in 18 bone marrow transplant recipients were analyzed retrospectively. These pneumonias could be divided into three diagnostic categories: (1) a transient form of nonspecific interstitial pneumonia resembling pulmonary edema in radiographic appearance occurred in five patients during the first 2 weeks after transplantation; (2) a fatal, progressive form of interstitial pneumonia began from 2 weeks to several months after bone marrow transplantation in seven patients; and (3) airspace pneumonias occurred in nine patients within 2 months of transplantation and were uniformly fatal. While the temporal and radiographic presentation of transient early interstitial pneumonia is often characteristic and may not require biopsy for diagnosis, the airspace and progressive interstitial pneumonias affecting bone marrow transplant recipients present variable patterns that are often radiographically indistinguishable. The direct pulmonary toxicity of high-dose total-body irradiation and chemotherapy may be contributory in producing both the early transient and later progressive forms of nonspecific interstitial pneumonia.