Challenging Case: 2 Year Old With "Autistic Behaviors".

Area of Science:

• Pediatric Developmental Neurology
• Clinical Genetics
• Rare Genetic Disorders

Background:

• A 2-year-old boy presented with global developmental delay and autistic behaviors, initially not meeting criteria for autism spectrum disorder.
• Early intervention and therapies were initiated, but concerns about autism persisted among providers.
• Initial genetic testing, including Fragile X analysis and chromosomal microarray, was inconclusive.

Purpose of the Study:

• To re-evaluate a child with persistent developmental delays and behavioral concerns using advanced genetic testing.
• To identify the underlying genetic cause of the patient's complex neurodevelopmental presentation.
• To guide future care and support strategies based on a definitive genetic diagnosis.

Main Methods:

• Clinical evaluation for global developmental delay and autistic behaviors.
• Initial genetic testing: Fragile X analysis and chromosomal microarray.
• Follow-up genetic testing with whole-exome sequencing (WES) after technological advancements.

Main Results:

• Whole-exome sequencing identified a rare, autosomal dominant mutation.
• The mutation is associated with a multisystem disorder including significant neurodevelopmental compromise, limited speech, behavioral issues, and craniofacial anomalies.
• The diagnosis shifted from global developmental delay to a specific rare genetic condition.

Conclusions:

• Accurate genetic diagnosis is crucial for understanding complex neurodevelopmental disorders.
• Whole-exome sequencing can identify rare genetic mutations missed by earlier testing.
• Identifying the specific genetic mutation guides tailored therapeutic interventions and family support for rare diseases.