Endocrine Abstracts

UPD is a congenital disease characterized by the presence of two homologous chromosomes inherited from one parent in a diploid offspring. Its effects can be dramatic when the expression of essential genes is lacking. This is due to a phenomenon known as genomic imprinting where only one of the two chromosomal copies is active, depending on the parent of origin. Maternal uniparental disomy of the chromosome 14 (UPD 14 mat) is a rare disorder characterized by prenatal and postnatal growth retardation, neonatal hypotonia, feeding difficulty, motor development delay, mild to moderate intellectual disability, mild facial dysmorphism, truncal obesity, small hands and feet, short stature and precocious puberty. Here we report a case of mosaic UPD(14)mat. G.N. is a girl born to a healthy mother with negative family history for genetic diseases. She was delivered at 37 weeks. Birth weight was at 20^th centile, height at 18^th centile. She displayed feeding difficulty and week sucking, hypotonia, micrognathia, low-set ears, hypertelorism, open foramen ovale, agenesis of the left hand. At the age of one year she practiced genetic examination with evidence of mosaicism 47XX+mar/46XX; so, she was diagnosed with UPD 14 mat. At the age of 6 years, she came to our Clinic for precocious puberty and growth rate reduction (−2 SD). Height was at 25^th centile, weight at 3^th centile, Tanner stage B2PH3. She presented with normal motor development and intellectual ability. Her physical features were normal; her craniofacial features included minimal ocular hypertelorism and slightly depressed nasal bridge. ECG, ultrasound thyroid and abdominal examinations were normal. The uterus had normal length and ovaries multiple sub-centimetric follicles. Bone age was 7 years. MRI displayed a normal pituitary gland. All the following hormones were in the normal range for gender and age: LH, FSH, 17BEstradiol, Testosterone, TSH, IGF-1. Tests by Arginine and Clonidine showed a pathological GH peak value while GnRH test demonstrated a puberal peak values of gonadotropins; so the patient was diagnosed with growth hormone deficiency (GHD) and precocious puberty.Therapy with Triptorelin and rhGH was prescribed. After six months, therapeutic efficacy was confirmed because the patient’s height increased by 5.5 cm and there was no progress of her secondary sexual characteristics. This is the first case described in UPD (14) mat in the form of a mosaic. Mosaicism limited the clinical features while some somatic defects and endocrinological disorders persisted. Therapy applied was effective at control after one year.