A rare cause of fetal ascites: A case report of Günther's disease.

Despite an arsenal of ever-improving diagnostic tools, determining the precise etiology of fetal ascites is not always possible. We report a case history where moderately-severe fetal ascites was retrospectively determined to be due to Günther's disease (congenital erythropoietic porphyria). The infant was found to carry the mutation associated with the most severe disease phenotype in which fetal hydrops has been described.