Cyclic neutropenia (CN) is a congenital, inherited disorder of white blood cell production. Its most characteristic feature is regular, periodic decreases in the numbers of circulating neutrophils (neutropenia). Neutrophils are a type of white blood cells produced in bone marrow. They are major players in combating infections caused by invading bacteria, viruses, and fungi.
A rare blood disorder in which patients suffer recurring fevers and infections, oral ulcers, and malaise and are found to have periodically depressed numbers of neutrophils in the blood. Cyclic neutropenia can be treated with drugs that stimulate neutrophil production.