Major clinical improvement in a boy with developmental disabilities and a PTPN4 mutation with intensive re-education and an enriched environment in a day care hospital: a case report

BACKGROUND: Protein tyrosine phosphatase, non-receptor type 4 (PTPN4) is a gene involved in glutamate downstream signaling contributing to cerebral maturation. Loss-of-function of this gene has been reported in patients showing various neurodevelopmental disorders, although the PTPN4 gene is not clearly considered a disease-causing gene in the Online Mendelian Inheritance in Man catalogue. CASE PRESENTATION: Here, we report the case of a 7-year-old white boy with a homogeneous, heterozygous, 170 kb chromosomal deletion encompassing several exons of the PTPN4 gene. The mutation was transmitted by his father, who had an undiagnosed communication disorder. The patient was referred to a day care unit for complex neurodevelopmental disorders and a suspicion of autism spectrum disorder. He had a severe communication disorder associated with sensory integration issues, anxiety, and elimination disorder. During his 4 years in the day care hospital, he received educational, creative, and academic group activities and specific re-education. Group activities help generalize the newly acquired developmental skills by providing social reinforcers and opportunities for positive peer interactions. In turn, achieving social activities positively influences the patient's self-esteem, emotional insight, and motivation to make new progress. CONCLUSION: Despite a severe communication disorder associated with sensory integration issues, anxiety, and elimination disorder, a diagnosis of autism spectrum disorder was ruled out, and remarkable progress was observed, which allowed our patient to attend same-age mainstream schools with personalized support at discharge. This case illustrates the effect of dimensional interventions to limit developmental impairments in a context of PTPN4 mutation and the benefit of providing an enriched environment in combination with individual re-education to improve developmental outcomes.