title: Deceleration of intellectual development in a XXXXY child: a follow-up.
mesh_terms: D002675:Child, Preschool; D006801:Humans; D007223:Infant; D008607:Intellectual Disability / Q000209:etiology*; D007713:Klinefelter Syndrome / Q000150:complications*; D008297:Male; D013997:Time Factors