Use of growth hormone and gonadotropin releasing hormone agonist in addition to L-thyroxine to attain normal adult height in two patients with severe Hashimoto's thyroiditis

AIM: We report two patients with severe acquired juvenile hypothyroidism who presented with compromised predicted adult height (PAH), and the successful use of growth hormone (GH) and gonadotropin releasing hormone agonist (GnRHa) in addition to L-thyroxine to attain normal adult height. PATIENTS AND RESULTS: Patient 1: 13 year-old girl who presented with pubertal delay, short stature (height SDS -4), and marked bone age retardation (BA 8 yr). Serum T4 was undetectable and TSH level was 1,139 mIU/l. After 1 year of treatment with L-thyroxine, growth rate improved from 1.0 cm/yr to 9.8 cm/yr but puberty progressed (Tanner 3 breast) and BA accelerated by 4 years, compromising predicted adult height (PAH) (144 cm vs mid-parental target height MTH] of 163 cm). Combined use of GH and GnRHa for one year slowed BA progression, and catch-up growth (10.4 cm/yr) continued to attain a final height (FH) of 155 cm. Patient 2: 14 year-old boy with undetectable T4, TSH of 811 mIU/l in mid-puberty with poor growth rate (1.0 cm/yr), without any bone age delay (BA 14 years) but compromised PAH (163.8 cm vs MTH 174 cm). Because of the advanced puberty and poor growth rate, treatment with GH and GnRHa was initiated. Treatment for 2 years led to improvement of growth velocity (10.6 cm/yr), slowed BA progression to attain a FH equal to MTH. CONCLUSION: Combined use of GH and GnRHa improved the FH of two patients, with Hashimoto's thyroiditis: one with pubertal and bone age delay and the other with normal onset of puberty and normal bone age.