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- What are the concerns regarding rhGH therapy in children with TS?
Recombinant hGH therapy in children with TS is associated with an
increased risk of kyphoscoliosis, slipped capital femoral epiphysis, and
benign intracranial hypertension, as compared to children with isolated
GHD or idiopathic short stature. Lymphedema may reappear in some chil-
dren after initiation of rhGH therapy. There was concern regarding increased
incidence of aortic dilatation and dissection with rhGH therapy; however, it
has been refuted in long-term studies. Patients with TS are predisposed for
the development of diabetes mellitus; however, therapy with rhGH does not
increase this risk, despite worsening of insulin resistance. Children with TS
who have Y-cell line are at an increased risk for the development of gonado-
blastoma/malignant germ cell tumors and theoretically, rhGH therapy may
further increase the risk. However, there is limited data to support or refute
this concern, as most of the studies of rhGH therapy in children with TS
either have not included patients with Y-cell line or have included them
after gonadectomy.- What are the benefits of rhGH therapy other than improvement in linear growth
in children with TS?
Apart from increased linear growth, rhGH therapy is associated with improve-
ment in facial features, body proportions, and body composition. Decreased
diastolic blood pressure and favorable lipid profile are other benefits of rhGH
therapy. The data regarding the beneficial effects of rhGH on bone mineral
density are conflicting; however, it seems that GH is important for the mainte-
nance of BMD in prepubertal children with TS, while estrogen plays a key role
in accrual of peak bone mass during peripubertal period.- What are the strategies to improve final adult height in children with TS, in
addition to rhGH therapy?
The strategies to improve final adult height, in addition to rhGH therapy include
oxandrolone, delayed induction of puberty, and use of low-dose estrogen ther-
apy during childhood. In a recent study, it was shown that oxandrolone therapy
initiated at the age of 9 years resulted in a height gain of 4.6 cm, despite the
induction of puberty at 12 years of age. In the same study, it was also shown
that delaying the pubertal induction till the age of 14 years resulted in a height
gain of 3.8 cm, without oxandrolone. However, combining these two strategies
(oxandrolone and delayed induction of puberty) did not result in any additional
gain in height. Because of adverse effects on psychosocial development and
bone health, delay in induction of puberty is not recommended as a measure to
improve height in patients with TS. In another study, it was shown that low-
dose estrogen therapy initiated during childhood (as early as 5 years), along8 Turner Syndrome