Myeloperoxidase Deficiency

Hereditary myeloperoxidase deficiency has been described recently as an autosomal recessive leukocyte disorder, associated with defective candidacidal activity in leukocytes and apparently with enhanced susceptibility to systemic candida infection. The neutrophils and monocytes of a patient with hereditary myeloperoxidase deficiency and systemic candidiasis were studied by means of gel diffusion, quantitative precipitation and immunofluorescence. Myeloperoxidase was immunologically absent in the leukocyte granule fractions of intact neutrophils and monocytes of the patient, and its characteristic absorption spectrum was not detectable. Structurally distinct eosinophil peroxidase was present. In genetically determined leukocyte myeloperoxidase deficiency, either the enzyme is completely lacking or it is structurally altered in its enzymatic, heme-binding and antigenic sites.