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The yield of the medical evaluation of children with pervasive developmental disorders
Thomas D Challman1, William J Barbaresi, Slavica K Katusic
1Department of Pediatric and Adolescent Medicine, Division of Developmental and Behavioral Pediatrics, Mayo Clinic, 200 First Street SW, Rochester, Minnesota, USA. tdchallman@geisinger.edu
Insights
Medical evaluations for pervasive developmental disorder-not otherwise specified (PDD-NOS) and autistic disorder yield similar etiological findings. Genetic disorders are common, suggesting a broad diagnostic approach for autistic spectrum disorders.
Area of Science:
- Developmental Neuroscience
- Pediatric Neurology
- Clinical Genetics
Background:
- Limited data exists comparing the diagnostic yield of medical evaluations for pervasive developmental disorder-not otherwise specified (PDD-NOS) versus autistic disorder.
- Autistic spectrum disorders encompass a range of neurodevelopmental conditions with varying underlying etiologies.
- Understanding the prevalence of identifiable medical conditions in these diagnoses is crucial for comprehensive patient care.
Purpose of the Study:
- To compare the yield of identifying etiologically relevant medical conditions in children diagnosed with PDD-NOS versus autistic disorder.
- To determine if the diagnostic category influences the likelihood of uncovering an underlying medical cause.
- To inform the scope of etiological investigations in children with autistic spectrum disorders.
Main Methods:
- Retrospective review of medical records for 182 patients under 18 years old.
- Patients were diagnosed with either PDD-NOS or autistic disorder and evaluated between 1994 and 1998 at Mayo Clinic.
- Identification and categorization of etiologically relevant conditions, including genetic disorders, seizure disorders, and neuroimaging/EEG abnormalities.
Main Results:
- An etiologically relevant condition was identified in 5.1% of patients with PDD-NOS (6/117) and 3.1% of patients with autistic disorder (2/65).
- Genetic disorders (chromosomal and single-gene) were the most frequently identified conditions in both diagnostic groups.
- Seizure disorders, abnormal electroencephalograms (EEGs), and brain imaging anomalies were common findings across both PDD-NOS and autistic disorder cohorts.
Conclusions:
- The likelihood of identifying an etiologically relevant condition appears comparable between children diagnosed with PDD-NOS and autistic disorder.
- The specific diagnostic label within the autistic spectrum disorder may not dictate the probability of finding an underlying medical cause.
- Etiological evaluations for children with autistic spectrum disorders should not be restricted by their specific diagnostic classification, advocating for a comprehensive approach.
Abstract:
Little information is available regarding the yield of the medical evaluation of children diagnosed with pervasive developmental disorder-not otherwise specified (PDD-NOS) compared to children diagnosed with autistic disorder. Medical records were reviewed for 182 patients less than 18 years of age with either PDD-NOS or autistic disorder evaluated between 1994 and 1998 at Mayo Clinic. A condition likely to be etiologically relevant was identified in 6/117 (5.1%) patients diagnosed with PDD-NOS and 2/65 (3.1%) patients diagnosed with autistic disorder. Genetic disorders, both chromosomal and single-gene, were the most commonly identified conditions. Seizure disorders, electroencephalogram abnormalities, and anomalies on brain imaging were common in both groups. The likelihood of uncovering an etiologically relevant condition in children diagnosed with either PDD-NOS or autistic disorder may be equivalent. The scope of the etiological search in an individual patient with an autistic spectrum disorder should not be limited by the specific diagnostic category.
