Background: Sotos syndrome is characterized by overgrowth. The four mayor criteria for diagnosis are: overgrowth (accelerated bone age), macrocephaly, characteristic facial features and developmental delay. They can also present escoliosis, heart or genitourinary disease, seizures, hypotonia, cerebral malformations, feeding difficulties, hearing loss and a greater risk of tumours.
Case report: A 10 months old girl was referred for overgrowth. BW and BL was over p99 since birth. Normal pregnancy with single umbilical artery. Caesarean section at term due to failure to progress. BW 4320 g (P>99, 2.68 DE), transient respiratory distress and mild hipoglucemy in the first hours of life, required admission in neonatology unit. Normal metabolic screening. Breastfeeding 8 months. She was evaluated for congenital torticolis at 2 months of age, and at 7 months of age the neurosurgical team ordered a CT scan to study plagiocephaly and dolicocephaly, considered normal. Abdominal ultrasound (due to single umbilical artery) showed renal duplicity with ectasia and ovarian cysts (1214 mm). 10 months old: BW 3.25 S.D., BL 3.65 S.D., HC 3.2 S.D.. Characteristic facial features, large hands and feet, large mandible, hypertelorism with macrodolichocephaly and a sacrococcygeal malformation. Normal Blood test and kariotype 46, XX. BA 18 m with CA 12 m, BA 5 years with CA 3.5 years old. 2 years old: Mild developmental delay, learning disabilities, problems with speech and language. Sacrococcigeal MRI no neurological malformations. Normal EEG. Brain MRI will have the results soon. Mutation in the NSD1 gene in 5q35 (heterocigous change of C-T in the exón 4 p.Arg788Term).
Conclusion: Mutations in the NSD1 gene are the primary cause of Sotos syndrome 90% of cases. An early diagnosis would help to avoid the use of x-ray (CT scan) or innecessary exams if it possible, and to focuses in associated complications. Early notification of special educational needs should be ensured.