The value of amniotic fluid diamine oxidase estimations in the management of severe rhesus iso-immunization.

Serial estimations of the enzyme, diamine oxidase (D.A.O.) in liquor amnii were made in 82 rhesus sensitised women. Normal levels were found in severe disease with a favourable fetal outcome, but abnormal levels were found in 50% of the pregnancies in which severe disease was associated with fetal death. In addition, when liquor bilirubin levels predicted moderate-severe disease, D.A.O. levels were abnormal in 75% of the pregnancies in which the fetus succumbed. Abnormally low D.A.O. levels in amniotic fluid were frequently associated with the subsequent development of disseminated intra-vascular coagulation in the infant. Serial estimations of D.A.O. in amniotic fluid could be a helphful adjunct to serial liquor bilirubin estimations in the management of severe rhesus iso-immunisation.