1988 Volume 29 Issue 5 Pages 733-737
A nontransfused 10-month-old female infant was admitted for the evaluation of persistent neutropenia, with absolute neutrophil counts ranging from 0 to 150/μl. Antibodies against neutrophils were investigated by indirect immunofluorescence and microleukocyte agglutination. The patient's sera reacted with neutrophils from her mother and normal donors having the netrophil antigen NA1, but not with neutrophils from NA1-negative donors. The results of lymphocyte cytotoxicity test were negative. After the absorption of the patient's sera with NA1-positive neutrophils, the antibody activity was completely abolished. No antibody against NA1-positive neutrophils was found in her mother's serum.
These results indicate that her neutropenia is caused by autoantibody against neutrophil specific antigen NA1.
