Abstract
Summary. Determinations were made of the activity of β-glucuronidase in serum, cerebrospinal fluid and urine from patients suffering from different mental and neurological diseases. The results were compared with the results from similar determinations on normal persons. An increase in activity was found in cases of epilepsy. While no explanation can be given for the above observation, the present results and those found in the literature lead to the conclusion that a high β-glucuronidase activity is not specific to cancer, in spite of the claims by a number of investigators.