One of the most frequent isolated, chronic, acquired neutropenias diagnosed in infants or toddlers:
Diagnosed during the first year of life (median age 8 months, range 3–36 months). Neutrophils can reach levels <0.2 x 109 /L, often accompanied by mild monocytosis. Neutropenia is typically detected during the occurrence of an acute febrile illness. Typically asymptomatic, but some cases neutropenia may be accompanied by minor infections. Serum anti-neutrophil antibodies may be positive. Rarely associated with other autoimmune disease. Usually resolves spontaneously before the age of 5 years, mean duration 17 months.
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