Case report: long-term follow-up of a 45,X male with SHOX haploinsufficiency.

The 45,X disorder of sexual differentiation (DSD) is a rare disorder. We report long-term follow-up of a 5-year-old African-American male whose evaluation for short stature revealed a karyotype of 45,X der(X)t(X;Y)(p22.3;p11.2)(SRY+). Presence of the SRY (sex-determining region Y) gene resulted in his male development. His chromosome abnormality also resulted in a deletion of the SHOX (short stature homeobox-containing) gene, which partly contributed to his short stature and skeletal features. He underwent normal spontaneous pubertal development, but his final height remained compromised due to advanced bone age, non-optimal response to recombinant human growth hormone (rhGH) treatment during the period of compliance and ultimately non-compliance with rhGH therapy. To our knowledge, this is the first case report describing long-term follow-up of a 45,X male DSD which highlights the similarities and differences from Turner syndrome females.