Endocrine Abstracts

Introduction: 45XO/46XY karyotype has varied phenotypic spectrum ranging from short stature, ambiguous genitalia (60%), clinical signs of Turner’s syndrome in both males and females and normal male phenotype. We report six phenotypically male cases with a varied clinical presentation.

Case 1 and 2: Short stature: Two pre-pubertal, phenotypical males, were referred with concerns regarding short stature (height <0.4th centile, height velocity – 2.6 cm/year). Chromosomes showed 45XO/46XY karyotype in both the boys. Both were commenced on GH with height SDS change of +1 SDS. Renal scan, echo was normal.

Case 3 and 4: Antenatal diagnosis: The first child’s antenatal CVS showed 45XO/46XY/46X ring Y chromosome which was confirmed on postnatal testing (indication was previous sibling with Trisomy 21). The second child with 45XO/46XY karyotype had an antenatally diagnosed nasal glioma. Both were phenotypical male. Both continue to grow within target centile range with normal echo and renal scans.

Case 5 and 6: Ambiguous genitalia: The first child was born preterm at 30 weeks following an IVF pregnancy and was referred with concerns of ambiguous genitalia. The child was phenotypically male with palpable gonad in the right scrotum and left gonad in the inguinal region, severe hypospadias and penoscrotal web. He continues to grow well.

The other child was referred to urologist at 3 months of age, with chordee and hypospadias with B/L descended testes. He was started on GH at 4 years of age with an excellent response and height SDS change of +1 SDS. Both had 45XO/46XY karyotype.

Conclusion: In summary, karyotype analysis should be performed more regularly when investigating short stature in males outside of target centile range particularly those with urogenital anomalies, as is recommended in short stature for girls. These young people should be followed up regularly as they tend to respond well to GH treatment but also to monitor for late onset problems such as gonadal tumours and infertility.