[True hermaphroditism in a child with a chimeric XX/XY chromosome, a double erythrocyte population and an unusual Lewis (a+ b+) phenotype].

A 2 years-old Korean girl is seen because of ambiguous external genitalia. Surgical exploration shows the right gonad to be an ovary and the left one to be an ovotestis, thus demonstrating a true hermaphroditism. Cytogenetic studies of peripheral lymphocytes reveal a mixture of 46,XX and 46,XY cells, with a predominant XX cell line. The patient's red cells are composed of two distinct populations differing in three genetically independent blood group systems. The ratios of the two cell lines in various tissues, especially among the cells secreting Lewis antigens, appear to be very different and suggest several hypothesis to explain the highly unusual red cell Lewis phenotype Le (a+ b+). We conclude to a dispermic chimera, however the adopted status of this child prevents any identification of the maternal or paternal contributions. Because of the physical aspect it was decided to remove the ovotestis, to repair the external genitalia and to bring up this child as a female.