Endocrine Abstracts

Temple syndrome is due to loss of methylation at 14q32. Features are prematurity, low birth weight, hypotonia, feeding difficulties, short stature and early puberty, as well as small hands and feet, mild learning disability and variable obesity. We report monozygotic twins with Temple syndrome. Twin1 was born at 31+2 weeks with mild SGA (1120g, <10^th centile), head circumference 27 cm, undescended testes, severe hypotonia and laryngomalacia. He developed camptodacyly, mild learning difficulties and scoliosis requiring rodding. He started Levothyroxine for mild hypothyroidism aged 2 months. Glucagon testing showed a GH peak of 7.6 ng/mL with normal IGF1. IGF1 continued to be in the lower third of the normal range with a low normal IGFBP3. He received GH for SGA from age 9.5yrs when his height was −2.7S.D.. He responded well, but developed CPP with quickly progressing puberty. Bone age was 12.0yrs at a chronological age of 10.8 yrs. GnRHa was started with delay due to the pandemic, aged 11.2yrs when height was −0.86S.D. and testes volumes 12/12 mL. At 12.8yrs his height was 144.8 cm (−1.13S.D.), height velocity (HV) 3.1 cm/yr, BMI 22.3 kg/m² (+1.60 S.D.), G3P3A2 testes 8/8–10 mL and advanced bone age of 14.0 yrs. His twin brother was born without SGA and did not receive GH treatment. He had bilateral camptodactyly, mild scoliosis and absence of lateral incisors. His pubertal onset was before the age of 10, but he had reduced follow up due to COVID, and was well developed into puberty (P3G3A2 testes 8/10–12 mL) with a good growth spurt (9.7 cm/yr) at 11.2 yrs. GnRHa was not started. Bone age was 12.66 yrs at CA 10.8yrs. At 12.8 yrs, his height is 145.8 cm (−1.0 S.D.), height velocity 1.9 cm/yr, BMI 22.1(+1.5S.D.), G3P3A2, testes 12–15 mL with an advanced bone age of 16.3 yrs. 100K genome study revealed no abnormalities. 14q methylation testing was performed subsequently which revealed Temple Syndrome. In conclusion, Temple syndrome needs to be considered in patients with short stature and additional features or an SRS like phenotype. A combination of GH and GnRHa may improve final height.