ESPE Abstracts

Background: Sotos syndrome is a rare syndrome; with distinctive clinical findings include typical facial appearance, learning disability; and overgrowth. Advanced bone age can be detected in some cases while precocious puberty reported only in two cases until now.

Case: A 6,5 months of age male infant admitted to clinic with neuromotor delay and macrogenitalia. He was second child of unrelated healthy parents, and birth-weight was 4200 g. In physical examination: height: 75 cm (HSDS: +2,3), weight: 10.5 kg, RBMI was 90%, testicular volume 4 ml bilaterally, penis length was 6.7 cm. Mild facial dysmorphism with global developmental delay were noticed. In laboratory evaluation, high basal testosterone level (88 ng/dl), and high basal and stimulated gonadotropins (bLH: 1.56 mIU/ml, bFSH: 1.02 mIU/ml, stimulated LH: 43.3 mIU/ml, stimulated FSH: 3,65 mIU/ml) were confirmed central precocious puberty. Cranial imaging studies revealed normal pituitary gland. Bone age was 1 year. LHRH analogue at dose of 250 mcg/kg/month was started. Because the HHG axis was not controlled efficiently, the dose of LHRHa increased to 500 mcg/kg/month. At the age of 2,5 years, increase of testicular volume to 8 ml and penile length to 9 cm were detected. Bone age advanced to 4.5 years. Cyproterone acetate 50 mg/day was added to treatment. With combined treatment, patient’s clinical and laboratory progression was controlled. As his phenotype was resembled to Sotos syndrome, we performed NSD1 analysis and detected a heterozygous mutation NM_022455.4:c.5177C>G(p.Pro1726Arg).

Conclusion: Central precocious puberty can be accompanied with Sotos syndrome, and overgrowth can be related either to syndrome itself, and precocious puberty. Treatment can also be very challenging with required high dose and combined treatment. Although we can not explain the reason of central precocious puberty in Sotos syndrome, it can be related to mutation characteristics of NDS1, or other underlying reasons that need to be demonstrated.