Perspectives on growth promoting treatment for patients with Turner syndrome in Japan

In Japan, anabolic steroid hormone (ASH) treatment for Turner syndrome (TS) to promote growth had been provided before GH therapy for TS was approved. ASH effectively improved the adult height (AH) of TS patients without spontaneous puberty but decreased the AH of TS patients with spontaneous puberty. Although GH therapy for TS was approved in 1991, the approved dosage remained 0.5 IU/kg/wk for GH-deficient TS patients and improved AH by approximately 7 cm. However, AH did not reach –2 standard deviations in healthy girls. In 1999, the requirement of GH deficiency was removed and a dose of 1.0 IU/kg/wk was approved. Although an increase in AH was expected, no reports showed significant improvements in AH at a high dose of GH. GH + ASH combination therapy was reevaluated and recommended for TS patients with gonadal failure and an extremely short stature or those who respond poorly to GH therapy. Although early estrogen replacement therapy is recommended to improve psychological quality of life and prevent osteoporosis, it lowered AH even at a low dose of ethinyl estradiol (25 ng/kg/d). The initiation of ethynyl estradiol at an extremely low dose (1–5 ng/kg/d) at a relatively young age successfully improved AH.