Refers to individuals of African descent with neutrophil counts less than 1.5 x 10th to the 9th in the absence of other causes.
Clinical distinct disease than congenital neutropenia, cyclic neutropenia and chronic idiopathic neutropenia, seen most in white individuals and have white blocc cell counts which are very low, less than 0.5 x 10 to the 9th.
While most common in African-Americans, but case reports exist for white people.
Outside of the US 25-40% of individulas of African descent may have this disorder (Weingarten MA).
Prevalence decreases with age: 4% in adult African-american men and 2%-3% in adult African American women, compared with les than 1% in whites (Hsieh MM).
Diagnosis requires resial testing with absolute neutrophil counts of less than 1.5 x 10 to the 9th cell/L over many months.
Counts generally are at least 1.0 x 1o to the 9th cells/L.
Not associated with increased risk of local or systemic infections and no significant increases in lymphocytes or monocytes is seen.
Presumed to be normal individuals nad no additional treatment is required for the presence of infections.
Bone marrow examination show normal cellullarity and leukocyte maturation (Mason BA,).
Africans and Caribbeans of African descent have been shown to have lower numbers of myeloid bone marrow precursors than white controls (Rezvani,K).
African-Americans have normal stem cell numbers, normal white cell maturation but have a minor reduction in myeloid progenitors at steady state.
Patients have a lower physiologic release of neutrophils from the vascular endothelium and from bone marrow stores.
Neutrophil response after the administration of corticosteroids is low in patients with this process, and disproves that neutrophil margination in the vascular endothelium is the cause for this entity.