Growth Hormone Dynamics among Children with Mixed Gonadal Dysgenesis (45,X/46,XY).

CONTEXT: Learn the growth hormone dynamics and discuss the issues of growth hormone therapy in subjects with 45,X/46XY.

OBJECTIVE

To study the growth hormone dynamics in children with 45,X/46,XY karyotyping and mixed gonadal dysgenesis (MGD).

DESIGN

Descriptive clinical study.

PARTICIPANTS

Five subjects with karyotype 45,X / 46,XY with or without genital ambiguity and somatic features of SHOX haploinsufficiency.

INTERVENTIONS: Growth hormone dynamic study and gonadectomy.

MAIN OUTCOME: IGF-1, peak GH levels, Turner's stigmata and histology of gonadal tissue.

RESULTS

Five cases of MGD with both male and female phenotype were studies. IGF-1 levels and GH levels showed both features of growth hormone deficiency and growth hormone insensitivity. One study subject has gonadal germ cell tumour (dysgerminoma). We discuss here the issues regarding the GH therapy in MGD subjects.

CONCLUSION

Growth deceleration in MGD subjects is partly due to defective growth hormone secretion and partly due to growth hormone insensitivity. MGD subjects are at high risk for occurrence of gonadal tumours. Gonadectomy or biopsy of underlying dysgenetic gonads is essential prior GH therapy. Close surveillance for second neoplasm is to be considered in subjects with history of gonadal tumors prior starting GH for short stature.