[Extremely high alpha-fetoprotein levels in a puncture specimen with few cells following amniocentesis and interpretation by sonography].

We report on a prenatal diagnosis with high alpha-fetoprotein level and a positive acetylcholinesterase activity in a presumptive amniotic fluid. Ultrasonographic examinations revealed a hydropic fetus with a nuchal cystic hygroma. Chromosome analysis of the aborted foetus ascertained the suspected Turner syndrome. The highly elevated alpha-fetoprotein concentration and the positive acetylcholinesterase activity as well as the absence of the cells in the fluid make it clear, that the punctate originated from a cystic hygroma. Other cases from the literature are discussed.