2018 Volume 64 Issue 1 Pages 66-71
The pre-transfusion test for patients with anti-John Milton Hagen (JMH), an antibody against high-frequency antigens, has been associated with difficulty in the identification of irregular antibodies as well as incompatibility with the cross-match test. Thus, establishing a transfusion for these patients can be problematic. Although anti-JMH usually exhibits IgG4 subclass, IgG4 appears to be of no clinical significance. We found that monoclonal anti-human IgG reagent, which had no reactivity to IgG4, provided useful information in compatibility testing in a patient with anti-JHM.
An 82-year-old male patient underwent a cross-match test via an indirect anti-globulin test, and was positive for the polyclonal anti-human IgG reagent but negative for the monoclonal version. Anti-JMH was identified in the test results at Japanese Red Cross Blood Center. An IgG subclass analysis using flow cytometry showed IgG4 positivity.
Based on the results of the monoclonal anti-human IgG reagent test, transfusion was performed. The expected outcome of the transfusion was achieved with no hemolytic side effects.
A monoclonal anti-human IgG reagent that does not react with IgG4 seems to be useful for checking alloantibody production after transfusion, and enables the reporting of cross-match test results that are valid for treatment, particularly in patients with anti-JMH.
