[Isoenzymes of creatine kinase in the perinatal period (author's transl)].

The serum of new-born children shows a higher catalytic concentration of creatine kinase than adult serum. These values reach normal adult levels within the first 10 days of life. In addition to the MM-, the MB- and BB-isoenzymes of creatine kinase are also found in the serum of women in labour, in cord-serum, and in the serum of newborn children. These findings should be taken into consideration in the analysis of creatine kinase isoenzymes.