Which are the symptoms?
Neutropenia should be suspected in patients with frequent, severe, or atypical bacterial and/or fungal infections. Confirmation is by CBC with leukocyte formula. Neutropenia remains asymptomatic until the infection develops. The severity of neutropenia correlates directly with the relative risk of infection. The infections that most frequently occur in patients with profound neutropenia are: cellulitis, furunculosis, pneumonia, and septicemia. Fever is often the sole indication of the infectious state. Typical signs of focal inflammation (erythema, swelling, pain, infiltrates) may be attenuated or absent. Local symptoms (e.g., oral ulcers) may appear, but in most cases they are minimal. The mechanism and cause of neutropenia must be determined. Family history or the presence of other concomitant diseases may help in suspecting a genetic origin.
How is it diagnosed?
Bone marrow examination is necessary to establish whether the neutropenia is due to reduced neutrophil production. Additional marrow studies are also performed. All these investigations help to narrow down the field of possible responsible genes (e.g. hairy cartilage hypoplasia syndrome, Chédiak-Higashi syndrome, dyskeratosis congenita, glycogenosis type IB, Shwachman-Diamond syndrome, WHIM syndrome, i.e. hypogammaglobulinemia warts, infections, myelocathexis]). Genetic analysis of peripheral blood is initiated with the aim of identifying the precise defect causing neutropenia.
How is it treated?
Most patients with severe congenital neutropenia will respond to chronic growth factor (G-CSF) therapy, but hematopoietic stem cell transplantation may need to be considered for patients with poor response.