RESUMEN
We studied the levels of carbohydrate antigen (CA 19-9, SLX, CA 50, Span-1, and Dupan-2) in serum, bronchoalveolar lavage fluid, and tissue from patients with benign bronchopulmonary disease. Patients had bronchiectasis, healed pulmonary tuberculosis, pulmonary fibrosis, or other diseases. Bronchoalveolar lavage fluid levels and immunohistochemical findings for lung tissue samples, in the absence of digestive and other diseases, suggested that elevated serum sialylated Lewis(A) (CA 19-9, CA 50, and Span-1) and Lewis(X) (SLX) antigen in patients with benign broncho-pulmonary disease are due to marked production of sialylated carbohydrate antigen in respiratory bronchioles. Common features of patients with benign bronchopulmonary disease include elevated serum carbohydrate antigen levels and bronchiectasis.