Neutrophil Oxidative Burst
Utility: 1) Functional evaluation of neutrophil oxidative burst potential.
2) Diagnostic screen for chronic granulomatous disease (CGD).
3) Detection of carrier status in female relative of CGD patient.
Specimen: 1 - 4 mL peripheral blood in sodium heparin (green top).
CPT codes: 88184, 88185, 88187.
Clinical indication/general description
CGD is a group of disorders characterized by a defective oxidative burst resulting in an inability to generate toxic oxygen radicals (superoxide) that are required to kill bacteria. Patients affected by this disorder present with recurrent bacterial infections or abscesses, particularly of the skin, subcutaneous areas or regional lymph nodes. In CGD, microbial killing is defective due to mutations in one of four known components of the NADPH oxidase system: one X-linked (gp91-phox) and three autosomal recessive (p22-phox, p47-phox and p67-phox).
This is a flow cytometric functional assay used to assess the ability of neutrophils to produce an oxidative burst. Neutrophils are loaded with dihydrorhodamine (DHR) dye and then activated with phorbol-12-myristate-13 acetate (PMA). Normal activated neutrophils produce superoxides that oxidize DHR resulting in the emission of fluorescence that is quantitated by flow cytometry. Neutrophils from patients with CGD cannot generate superoxide and therefore do not oxidize DHR.