45,X/47,XY,+13 mosaicism and Crohn's disease.

The unusual karyotype 45,X/47,XY,+13 in an 8.5-year-old girl with the Turner phenotype is described. She displayed none of the phenotypic manifestations of trisomy 13. The patient suffered from Crohn's disease, which is known to be associated with the Turner syndrome. To our knowledge this is the first reported case of Crohn's disease in a patient with 45,X and Y chromosome mosaicism.