INFLAMMATORY MEDIATORS IN BAL FLUID AS MARKERS OF EVOLVING PNEUMONIA IN LEUKOCYTOPENIC PATIENTS

Study objectives: Pneumonia during chemotherapy-induced leukocytopenia is a major cause of overall treatment failure in patients with hemato logic malignancies. To improve outcome in these high-risk patients, ea rly diagnosis of pulmonary infiltrates and institution of adequate ant imicrobial treatment are mandatory. To identify patients with evolving pneumonia, we have prospectively studied the prognostic value of cyto kine and complement measurements in early BAL samples from febrile leu kocytopenic patients. Design: Prospective, comparative study. Setting: Hematology/oncology section of a university hospital. Patients: Twent y-one patients with leukocytopenia (WBC count <1.000/mu L) following c ytoreductive chemotherapy for malignant disorders, Intervention: Early BAL sampling primarily for microbiologic diagnostic purposes. Measure ments and results: Proinflammatory cytokines and activated complement components were measured in the BAL aspirates and the results were rel ated to the prevalence or subsequent evolution of overt pneumonia. Of the 21 patients studied, 10 patients presented with overt pneumonia at BAL sampling (group A), 5 patients developed objective signs of pneum onia 3 to 5 days after BAL (group B), and 6 patients remained free of pneumonia during follow-up (group C), In comparison with group C, pati ents in groups A and B both had distinctly elevated bronchoalveolar le vels of tumor necrosis factor-alpha, interleukin-6, granulocyte colony -stimulating factor, C3a, and C5a, Conclusions: Cytokine and complemen t determinations in early BAL samples may aid in the identification of febrile leukocytopenic patients with evolving pneumonia 3 to 5 days p rior to the manifestation of diagnostic clinical and radiographic sign s.