Hyperreactivity to cow's milk in an infant with LE and tart cell phenomenon.

LE and tart cells were demonstrated in a black male infant whose serum contained milk-percipitating antibodies and who had pulmonary infiltrates. Immunoblasts, plasmocytoid lymphocytes, and an LE cell were found in a milk-stimulated skin window. The presence of LE cells corresponded to the presence of ENA antibody. Tart cells varied with oral milk challenge. A large Arthus type of skin reaction to injected milk was demonstrated. An oral feeding of milk resulted in a decrease in plasma C3. Lymphocyte transformation resulted from in vitro milk stimulation. ENA (extractable nuclear antigen) antibody and resulting LE cell formation possibly represented the combination of nuclear protein with milk antigen. The pulmonary infiltrates may represent a hypersensitivity pneumonitis characterized by both Arthus and cell-mediated reaction to milk.