Challenging Case: New-Onset Hallucinations and Developmental Regression in a Child with Autism Spectrum Disorder.

Nick is a 5-year-old boy who began displaying self-stimulating behaviors and decreased social interactions shortly before turning 3 years. At the age of 3.5 years, he was diagnosed with autism spectrum disorder by a local developmental-behavioral pediatrician. His parents recall that the physician described Nick to be "high functioning" and encouraged them to expect that he would attend college and live independently as an adult. Upon receiving the diagnosis, intervention was initiated using an applied behavioral analysis (ABA) approach. With this intervention, he demonstrated initial gains in the use of complex language and improved social interactions.Concerns regarding suspected psychosis emerged just before starting kindergarten when Nick began experiencing ego-dystonic visual and auditory hallucinations. Initially, Nick verbally responded to the hallucinations and vividly described what he was experiencing. Shortly after the onset of these hallucinations, Nick experienced a significant decrease in the frequency and complexity of his expressive language and became more withdrawn. Over time, his hallucinations intensified, and his parents became increasingly fearful for his safety. Various antipsychotic and mood-stabilizing medications, steroids, and immunotherapy have been trialed with limited improvement of his symptoms.An extensive medical evaluation yielded the following:1. Magnetic resonance imaging of the brain: dilated perivascular spaces.2. Urine organic acids: ketosis and increased lactic acid.3. Antinuclear antibody: minimally positive.4. Vitamin B12: elevated.All other studies, including lumbar puncture, electroencephalogram (awake and asleep), genetic studies (chromosomal microarray, fragile X testing, and whole exome sequencing), metabolic studies, inflammatory markers, and thyroid panel, were negative/normal.Nick is enrolled in a special education classroom within a school that utilizes an ABA-based approach for all students. As part of his educational programming, he receives 25 hours of ABA in a 1:1 setting, 2 hours of speech therapy, 3 hours of occupational therapy, 1 hour of physical therapy, and 30 minutes of music therapy weekly. Current concerns include significant head-banging and thrashing before falling asleep, hyperactivity, unsafe behaviors (e.g., banging on windows, climbing high to reach desired items), aggression toward caregivers, limited ability to complete self-care tasks (e.g., personal hygiene, toileting), significant decline in expressive language, and continued response to internal stimuli.Nick's parents now present to a multidisciplinary center seeking guidance regarding additional therapies/interventions to assist in management of his current developmental and behavioral challenges as well as information regarding his expected developmental trajectory as he reaches adulthood.