Leukocyte Peroxidase Deficiency in a Family with a Dominant Form of Kuf's Disease

Use of a spectrophotometric assay of peroxidase with p-phenylenediamine as cosubstrate demonstrated deficient enzyme activity in leukocytes from two patients with a dominantly inherited form of ceroid lipofuscinosis (Kuf's disease) and a clinically healthy unaffected sibling. When the reaction was performed in the absence of added hydrogen peroxide, oxidation of the p-phenylenediamine cosubstrate (indicating the presence of endogenous peroxide) occurred only with enzyme samples from the three siblings but not with those from a large number of unrelated, unaffected controls. This demonstrates that the deficiency of peroxidase found previously in the recessively inherited infantile and juvenile forms of ceroid lipofuscinosis (Batten-Spielmeyer-Vogt disease) is also present in an adult form with dominant inheritance.