Pulmonary infiltrates in leukemia.

We reviewed the inpatient records of 139 adult patients with leukemia to determine the incidence of opportunistic infections in immunocompromised patients and the pattern of roentgenographic involvement of such infections. There were 98 parenchymal infiltrates identified, including 43 episodes of local disease and 55 episodes of diffuse disease. The causes of the infiltrates were determined from biopsies of tissue and autopsies whenever possible. If roentgenographic resolution after therapy with an antibiotic or diuretic agent was documented, the cause was considered determined; however, this did not identify a specific bacterial or viral agent. Parenchymal infiltrates (17 episodes) appearing in the period before treatment or within 72 hours of initiating therapy were not opportunistic. Local disease during treatment was infectious in 23 (74 percent) of 31 cases and was bacterial in 20 (87 percent) of 23 cases. Opportunistic organisms caused only 13 percent of the local infectious episodes. Diffuse disease was noninfectious in 26 (65 percent) of 40 episodes; while in the 14 episodes of infectious disease identified, 13 (93 percent) were caused by opportunistic organisms. We conclude that procedures for biopsy to document opportunistic infection are of little value in local or diffuse disease before treatment, are of modest value in local disease during treatment, and are of greatest value in diffuse disease during treatment if little clinical evidence for noninfectious causes exists.