Neutropenia is defined as an absolute neutrophil count (ANC) of less than 1500/microliter in adults and 1000/microliter in infants under the age of 1-year. In benign neutropenia, as the name suggests, the condition is mild with ANCs ranging between 800 and 1400/microliter. This mild decrease in neutrophils is only seen in the circulating pool, with the bone marrow pools, marginal blood pools, and tissue pools of neutrophils displaying normal levels. Unlike other chronic neutropenias, benign familial neutropenia is not associated with an increased risk of infection, apart from cases of periodonitis. Affected individuals, for the most part, remain symptomless, and no treatment is required. The condition has been reported in certain families of European, African, and Yemeni Jewish origin.
Both hereditary and acquired forms of chronic benign neutropenia have been observed. The familial forms have been noted to follow an autosomal dominant mode of inheritance. However, the mechanism of pathogenesis is not known.