[Studies on transient hyperphosphatasemia].

We found 39 cases of transient hyperphosphatasemia (TH) from 8 primary medical care institutions over a 2.5 year period, beginning in 1986, and 36 cases were available for this analysis. The maximum activity of serum alkaline phosphatase (ALP) was 318 K.A unit, and 16 cases showed 100 K.A unit or more. Ages of the TH cases were ranged from 8 to 92 months and average of 25.4 months. There were no seasonal fluctuation of the incidence. Although high fever was noticed in 21 cases (58%), and diarrhea and upper respiratory infections were observed in 9 cases (25%) each, no common characteristic features in underlying diseases or laboratory abnormalities were noticed. All of those clinical signs were returned to normal within one month, except for 3 cases in which we could not make follow up study. ALP levels were re-examined within one week in 14 cases (39%) but re-examination was not requested in another 14 cases. ALP levels were returned to normal within one month but characteristic isoenzyme patterns for TH were detectable for up to 3 months from the onset. According to the investigation over 1.5 year period at Kumagaya pediatric hospital, 28 out of 7,287 samples (0.38%) were found to have TH. The mechanism to develop TH is not known, but sugar chain aberrations of ALP are more likely the cause, since viral infections were seen only a few occasions.(ABSTRACT TRUNCATED AT 250 WORDS)