An unusual alkaline phosphatase isoenzyme in a patient with concomitant marked elevation of acid phosphatase without clinical evidence of prostatic carcinoma.

An 81-year-old male with congestive heart failure and prostatic hypertrophy was found to have markedly elevated serum acid phosphatase (EC 3.1.3.2) and moderately elevated serum alkaline phosphatase (EC 3.1.3.1). Alkaline phosphatase isoenzyme analysis was performed to determine the organ source of the enzyme. There was an unsual slow-migrating alkaline phosphatase isoenzyme band in the serum of this patient suggestive of hepatic origin by a variety of biochemical tests.