What finding is indicative of neutrophil-specific granule deficiency?

Neutrophil-specific granule deficiency is characterized by a defect in the formation of neutrophil granules, which play a critical role in the immune response. One of the hallmark findings of this condition is the impaired ability of neutrophils to respond to chemotactic signals, particularly C5a, which is an important component of the complement system that attracts neutrophils to sites of infection and inflammation.

In healthy individuals, neutrophils migrate toward C5a, among other chemotactic factors, to reach and target pathogens effectively. However, in individuals with neutrophil-specific granule deficiency, this chemotactic response is impaired due to the lack of granules that contain necessary signaling molecules and receptors. This impairment leads to difficulties in mounting an effective immune response, resulting in increased susceptibility to certain infections.

The other findings, such as increased susceptibility to catalase-positive pathogens and recurrent bacterial infections without pus formation, are associated with different types of immunodeficiencies. Severe neutropenia indicates a low neutrophil count, which is not specifically indicative of granule deficiency but suggests other forms of immune dysfunction. Therefore, the characteristic feature of impaired chemotactic response to C5a is the most directly linked to neutroph