Prediction of pubertal growth at start of estrogen replacement therapy in turner syndrome

Early growth hormone treatment accelerates delayed onset of puberty in patients with growth hormone deficiency

We investigated whether growth hormone (GH) treatment could accelerate the onset of puberty in patients with isolated GH deficiency (GHD). Of the 135 boys and 89 girls who started GH treatment before the onset of puberty and were followed up at Tanaka Growth Clinic, 83 boys and 51 girls who started GH treatment sufficiently earlier than the average age at onset of puberty of GHD patients (<10 years vs. 11.7 years for boys; <9.5 years vs. 11.4 years for girls) were analyzed. Age at onset of puberty significantly positively correlated to age at the start of GH treatment (boys: r = 0.427, p < 0.0001; girls: r = 0.302, p < 0.05). When the subjects were divided into two groups each: for boys, Groups A (n = 45) and B (n = 39), treatment was started at age <8 and 8 to <10 years, respectively; for girls, Groups A (n = 26) and B (n = 21), treatment was started at age <7 and 7 to <9.5 years, respectively, age at the onset of puberty was significantly lower in Groups A than in Groups B by the Mann-Whitney U test (boys: p < 0.01; girls: p < 0.05) and Kaplan-Meier log-rank test (boys: p < 0.01; girls: p < 0.05). These results indicate that GH treatment accelerates the delayed onset of puberty in patients with GHD. Heights at the onset of puberty in Groups A and B were not significantly different, suggesting that early treatment does not increase adult height.

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.

Bone age: assessment methods and clinical applications

The main bone age assessment methods are the Greulich-Pyle and Tanner-Whitehouse 2 methods, both of which involve left hand and wrist radiographs. Several other bone age assessment methods have been developed, including ultrasonographic, computerized, and magnetic resonance (MR) imaging methods. The ultrasonographic method appears unreliable in children with delayed and advanced bone age. MR imaging is noninvasive; however, bone age assessment using MR imaging is relatively new, and further examinations are needed. An automated method for determining bone age, named BoneXpert, has been validated for Caucasian children with growth disorders and children of various ethnic groups. Sex hormones are necessary for bone growth and maturation in children with a bone age corresponding to normal pubertal age, and estrogen is essential for growth plate closure. Bone age is an effective indicator for diagnosing and treating various diseases. A new method for adult height prediction based on bone age has been developed using BoneXpert, in addition to the commonly used Bayley-Pinneau and Tanner-Whitehouse mark II methods. Furthermore, bone age may become a predictor for the timing of peak height velocity and menarche.