Mass-fragmentographic determination of catecholamine metabolites in amniotic fluid and its possible clinical usefulness.

We describe the determination of 3-methoxy-4-hydroxy-phenylacetic acid, 3-methoxy-4-hydroxyphenylamandelic acid, and 3-methoxy-4-hydroxyphenylethylene glycol in amniotic fluid by means of mass fragmentography, with use of deuterated internal standards. The results expressed in terms of absolute concentration and creatinine concentration, are given as a function of gestational age. In the 15th to 17th week, concentrations in amniotic fluid are a reflection of those in the mother's serum, whereas in the 32nd to 40th week, these concentrations, expressed in terms of creatinine, are similar to those found in the urine of newborns. We discuss the possible usefulness of the determination of catecholamine metabolites in amniotic fluid in the diagnosis of congenital neuroblastoma, maternal pheochromocytoma, and underdevelopment.