Hyperphosphatasemia related to three intestinal alkaline phosphatase isoforms: biochemical study.

An unexplained hyperphosphatasemia was noted in a healthy 47-year-old woman. The electrophoretic pattern on agarose gel with and without wheat germ lectin of the serum of this patient showed the presence of three isoforms which have been characterised as being of intestinal origin: their biochemical (neuraminidase, phenylalanine) and thermodenaturation properties are similar to those of intestinal tissue extract. The pI and pH optima of these isoforms agree with an intestinal origin. Our results suggest the existence of different allelozymes of intestinal alkaline phosphatase.