We report the case of a young boy with nonverbal autism and intellectual disability, with a rare de novo 1q21.3 microdeletion. The patient had early and extreme self-injurious behaviours that led to blindness, complicated by severe developmental regression. A significant reduction in the self-injurious behaviours and the recovery of developmental dynamics were attained in a multidisciplinary neurodevelopmental inpatient unit. Improvement was obtained after managing all causes of somatic pains, using opiate blockers and stabilizing the patient's mood. We offered both sensorimotor developmental approach with therapeutic body wrap and specific psychoeducation adapted to his blindness condition for improving his communication abilities.