Diagnostic significance of myeloperoxidase assay in neuronal ceroid-lipofuscinoses (Batten-Vogt syndrome).

In 13 patients with morphologically established juvenile neuronal ceroid lipofuscinosis and 13 controls, the activity of leukocyte peroxidase (myeloperoxidase) was determined under various conditions: Measurement of water-soluble enzyme, the buffer-soluble enzyme, and the leukocyte homogenate; application of phosphate buffer (pH7.0) and borate buffer (pH7.6); employment of 9mM, 28mM, and 55mMp-phenylenediamine as hydrogen donor; and measurement of the specific enzyme extinction at 10, 60, and 180 seconds. A significant difference between mean values for patients and controls could not be established. In both groups, single individuals exhibited definitely increased or reduced enzyme concentrations, leaving us, however, without an adequate explanation for these observations. Our studies indicate that determination of myeloperoxidase has no value in establishing the diagnosis of neuronal ceroid-lipofuscinoses.