Autoimmune and other acquired neutropenias.

This educational review addresses the diagnostic evaluation of patients for autoimmune and other forms of acquired neutropenia, including the futility of deconstructing the overlap of chronic "autoimmune," "benign," and "idiopathic" categories. Isolated neutropenias caused by infection, drugs, and immunologic disorders are also addressed. Discussion of management options emphasizes a conservative approach, with largely supportive care for these mostly benign and self-limited disorders.