Leukocyte Agglutinins in Collagen Disease

SummaryLeukocyte-iso-agglutinins were found in 18 of 40 patients with collagen diseases (rheumatoid arthritis, systemic lupus erythematosus, scleroderma, Felty's syndrome and other collagen diseases). Most frequently leukocyte agglutinins were found in systemic lupus erythematosus. A relation was found between the occurrence of leukocyte agglutinins and previous blood transfusions whereas no association between leukocyte agglutinins and pregnancies was demonstrable. Finally, leukocyte agglutinins were found in four patients who had not been subjected to iso-immunisation.Type specificity of the agglutinins could not be demonstrated. The leukocyte agglutinins were unrelated to red cell antibodies and to the L.E. factor.It is discussed whether leukocyte agglutinins may be a cause of leukopenia in collagen disease.