CITRULLINEMIA - PRENATAL-DIAGNOSIS OF AN AFFECTED FETUS

  • 1 January 1983
    • journal article
    • research article
    • Vol. 35  (1) , 85-90
Abstract
A pregnancy was monitored in a family at risk for citrullinemia due to argininosuccinic acid (ASA) synthetase deficiency. ASA synthetase activity in cultured epithelioid amniotic fluid cells from the fetus at risk was < 2% of control epithelioid amniotic fluid cell activity. An increased concentration of citrulline was found in the at-risk amniotic fluid (0.14 .mu.mol/ml) as compared with fluid from 6 controls and 1 at-risk but unaffected pregnancy (trace). The pregnancy was terminated, and the in utero diagnosis was confirmed by assay of ASA synthetase activity in cultured fetal skin fibroblasts (4.4% of control activity). All 5 fetal tissues studied had significant accumulation of citrulline, whereas control fetal tissues had none. If precise control is maintained over tissue culture variables, citrullinemia can be diagnosed successfully in utero by microassay of ASA synthetase activity in cultured amniotic fluid cells. Amniotic fluid citrulline concentrations seem to provide strong adjunctive evidence for this prenatal diagnosis.