Autoimmune neutropenia (AIN) is a rare clinical condition caused by granulocyte autoantibodies, which may occur either in children or adults, but which often remains undiagnosed. AIN commonly occurs in children between the ages of 6 months and 5 years. Autoimmune Neutropenia in Infancy tends to be a self-limiting autoimmune condition but can last several years. In adults, AIN presents as a chronic disorder either as an isolated (primary) neutropenia or as a neutropenia secondary to other disorders, such as rheumatoid arthritis, systemic lupus erythematosus, Felty's syndrome and chronic lymphocytic and large granulocyte leukaemias.
