Autoimmune neutropenia

What it means

Abnormal decrease of the absolute number of neutrophils in the blood, per microlitre, compared to a reference range for a given sex and age-group, accompanied by the detection of anti-neutrophil antibodies.

The antibodies are directed against the cell surface membrane and have no relationship with antineutrophil cytoplasmic antibodies (ANCAs) in the vast majority of cases. It is important to highlight that there are frequent difficulties in the detection of autoantibodies causing AIN due to the labile nature of granulocytes (not storable without activation and consequent autolysis). This type of neutropenia is commonly seen with autoimmune neutropenia of infancy (AIN), also called primary autoimmune neutropenia, is a disease in which antibodies recognize membrane antigens of neutrophils, mostly located on immunoglobulin G (IgG) Fc receptor type 3b (Fc-gamma-IIIb receptor), causing their peripheral destruction.

Rare diseases that can present with this12

The range is how often this sign appears among people diagnosed with each disease — it is not a probability of having any of them. Many of these signs also occur in common, non-rare conditions. A sign on this page is a conversation to have with a clinician, not a conclusion.

Part of the broader category

Also called: Neutropenia in presence of anti-neutropil antibodies