ESPE Abstracts

Introduction: Characteristic features in patients with a duplication at 5q35.2q35.3 encompassing NSD1 are short stature, microcephaly, mild developmental delay, behavioural problems, digital anomalies and defects of internal organs. The above-mentioned features are reversed to Sotos syndrome phenotype, which is associated with a microdeletion in the same chromosomal region. In the literature, 41 patients were reported so far.

Case report: Our patient was born at a gestation age of 39 weeks. Her birth weight was 2650g (-1,95 SDS), and her length was 49 cm (-0,85 SDS). At the age of 12 years and 2/12, the girl was admitted to the Department of Pediatric Endocrinology and Rheumatology at Poznan University of Medical Sciences for the diagnosis of short stature. She does not have any chronic illnesses and does not take any medication regularly. Bone age was delayed by half a year. Genetic testing showed a normal karyotype of 46, XX. The patient suffered from school problems and mild psychomotor developmental delay. The physical examination showed a normal and proportional body structure, with noticeable dysmorphic features such as hypertelorism, low-set hairline, bilateral clinodactyly of the fifth finger of the hand, narrow upper lip, and wide nasal base. The thyroid gland was palpable. Pubertal development was: Th2, P1, Ax1. Her height was 131,9 cm (-3,4 HSDS) and her weight was 26 kg (-2,8 SDS). Diagnostic tests showed normal thyroid function, with IGF-1 and IGFBP-3 levels within the normal range. Growth hormone deficiency and celiac disease were ruled out (max. growth hormone after glucagon 14,4 ng/ml). Thyroid ultrasound was normal. The patient's pubertal development proceeded normally, with the menarche occurring at the age of 15 years, and subsequent menstrual cycles were regular. According to auxological data at ages 5 years and 7 months calculated predicted adult height based on bone age was 151,5 cm. Despite significant short stature observed during developmental period, she reached the final height 152 cm (-2,3 HSDS) which is close to the predicted adult height calculated at the age of almost 6 years. The patient improved growth velocity during the pubertal spurt. The corrected final height was -1,61 SDS.

Conclusion: The reported patient in paediatric care demonstrated significant short stature, with the lowest HSDS -3,4. She improved growth velocity during the pubertal spurt and her final height was -2,3 HSDS. This is the first report showing a detailed pattern of growth in patient with confirmed duplication at 5q35.2q35.3 encompassing NSD1.