Incidence of children with autism spectrum disorder (ASD) is rising through the years with estimated 1 in 68 in the US in 2014. This incidence is also rising in the population of congenitally deaf children. Favorable outcome after early cochlear implantation is expected due to plasticity and reorganization capacity of brain in infants and toddlers, but outcomes could be significantly modified in children with diagnosed ASD. Current methods of screening for autism have difficulties in establishing diagnosis in children who have both autism and other developmental delays, especially at such an early age. The aim of the study was to assess the development of auditory perception and speech intelligibility in implanted children with profound congenital hearing loss who were diagnosed with ASD comparing to those who were typically developing.

Fourteen children underwent cochlear implantation; four were later diagnosed with ASD and ten were typically developing. All children underwent intensive postoperative speech and hearing therapy. The development of auditory perception and speech intelligibility was assessed using the Categories of Auditory Performance (CAP) and the Speech Intelligibility Rating (SIR) during the 5-years follow-up.

In children later diagnosed with ASD, auditory processing developed slowly. Depending on the individual capabilities, by the age of six they could identify environmental sounds or discriminate speech sounds. Speech Intelligibility in children with ASD was at best rated as category 2, with very little or no progress up to the age of six, despite extensive speech and language therapy. Communication skills were strongly affected by a degree of autistic features expression.

Preoperative psychological assessment in congenitally deaf infants should be expanded by the use of validated instruments for early detection of autism. The possibility of developing ASD should be kept in mind by all professionals involved in programs for cochlear implantation.