Immune Neutropenia

Immune Neutropenia

• Overview

  Versiti Diagnostic Labs comprehensive suite of diagnostic testing options address diverse variations of neutropenia disease states. Often, neutropenia is caused by antibodies that bind to neutrophils and clear them out of circulation more rapidly than normal. Antibodies can form against neutrophil-specific alloantigens and neutrophil antigens shared with other cells. Neutrophil antibodies are important to consider in clinical conditions including neonatal alloimmune neutropenia, autoimmune neutropenia, and drug-induced neutropenia.

• Approach

  Comprehensive, highly specific diagnostic assays for your specific patient.

  BloodCenter of Wisconsin, part of Versiti, boasts an internationally known laboratory that has always been on the forefront of clinical and scientific research in human neutrophil alloantigens. In fact, the molecular basis for HNA-3 was determined and reported by Dr. Brian Curtis, Scientific Director at BloodCenter. We remain dedicated to leading these efforts and delivering the information physicians need to diagnose, treat and enhance the lives of their patients.

  Autoimmune Neutropenia (AIN) - Primary AIN occurs in both adults and children as an isolated hematologic disorder not associated with other disease factors. Patients frequently present with neutrophil counts less than 500/mm3 and recurrent infections of mild to moderate severity. Neutrophil-reactive antibodies can be detected in the sera of patients with this disease, especially in children. Antibodies often show specificity for the HNA-1a antigen.
  
  Neutrophil antibodies and AIN also occur as secondary phenomena in other autoimmune diseases including systemic lupus erythematosus, Felty's syndrome, rheumatoid arthritis, and myasthenia gravis.
  
  Drug-induced Neutropenia - Flow cytometry has been shown to be effective in detecting some neutrophil drug-dependent antibodies. Many drugs including quinine have been implicated as causes of immune neutropenia.
  
  Neonatal Alloimmune Neutropenia (NAN) - In NAN, the mother is immunized by fetal neutrophil antigens inherited from the father. Maternal lgG antibodies cross the placenta and destroy fetal neutrophils. The most common neutrophil alloantigen incompatibilities are HNA-1a/b/c and HNA-2. Unlike its erythrocyte counterpart, hemolytic disease of the newborn, NAN can occur during the first pregnancy and may occur once in every 500 live births. Antibodies can be detected in the maternal serum by testing with a panel of normal donor neutrophils. Testing with the father’s neutrophils is necessary to detect antibodies to low frequency antigens. Neutrophil genotyping of both parents can be useful for confirming maternal antibody specificity and in providing counseling regarding future pregnancies.