Fetal gammaglutamyl transferase activity: clinical implication in fetal medicine.

In a retrospective study of 3,129 fetal blood samples, we first determined normal values for gammaglutamyl transferase (GGT) activity and found 33 cases with a mean GGT level of 961.8 U/l (prevalence 1.05%) corresponding to more than 10-fold normal values. In such extreme cases, elevations of GGT activity in fetal blood have been poorly studied. The goal of this work was to correlate this highly abnormal biological finding with pathological fetal conditions and try to better understand the pathophysiological mechanisms. The most frequent underlying disorders were infections (n = 11), renal or bowel malformations (n = 12) and genetic abnormalities (n = 5). Two cases of cystic fibrosis and one case of fetal alcohol syndrome were also encountered. In another 2 cases, no explanation was found.