Congenital erythropoietic porphyria (Günther's disease): two cases with very early prenatal manifestation and cystic hygroma.

Congenital erythropoietic porphyria (CEP) or Günther's disease is the rarest form of the porphyrias. The disease is usually diagnosed at birth or during early infancy, but rarely in utero. We describe here the first two cases of very early prenatal expression of CEP with cystic hygroma diagnosed at 14 weeks in the first fetus and at 19 weeks in the second. Both fetuses presented with severe nonimmune hydrops fetalis as early as 19 and 22 weeks, associated with intrauterine growth retardation, hyperechogenic kidneys and bones. Amniotic fluid was dark brown and uro- and coproporphyrin I was dramatically increased. Molecular screening of the CEP gene detected heterozygous C73R mutation in both fetuses, the other parental mutation being as yet unknown.