Introduction
Diagnostic overshadowing is a significant challenge in the medical field, especially when dealing with complex cases where multiple conditions may coexist. It refers to the misattribution of new symptoms to an already diagnosed condition, leading to potential delays in identifying co-occurring disorders. This is particularly relevant in the context of children who are deaf or hard of hearing (DHH) and are also on the autism spectrum. A recently published case study highlights how diagnostic overshadowing delayed the diagnosis of Autism Spectrum Disorder (ASD) in a child who is deaf, emphasizing the need for interdisciplinary approaches to ensure accurate diagnoses. With 40-50% of DHH children having additional medical or developmental conditions and autism prevalence in the United States estimated at 1 in 36 children, understanding and addressing these challenges is critical for timely intervention and support.
What is Diagnostic Overshadowing?
Diagnostic overshadowing occurs when healthcare providers attribute a patient’s symptoms solely to an existing diagnosis rather than considering the presence of a separate co-occurring condition. This often leads to delays in diagnosis and treatment, particularly when a patient has both sensory and developmental challenges. In the context of autism and deafness, the overlapping symptoms—such as communication delays, reduced social interaction, and difficulties in language acquisition—can easily be mistaken for effects of the sensory condition alone. This case study explores how these complexities played out in a young girl who was initially diagnosed with deafness, resulting in a delayed recognition of her autism.
The Case Study: Overview and Background
- Patient Profile: The subject of the study is a 2-year, 8-month-old girl diagnosed with profound bilateral sensorineural hearing loss. Her diagnosis of deafness came at 14 months old after her parents and pediatricians noticed a lack of progress in receptive and expressive language development.
- Initial Diagnosis: Following the identification of her hearing loss, she received bilateral cochlear implants at 22 months old. However, despite this intervention and consistent participation in speech and occupational therapy, she showed minimal improvement in language acquisition, both spoken and signed.
- Family Observations: The parents, noticing her persistent challenges in communication and reluctance to wear cochlear implant processors, began to suspect that something beyond her hearing impairment was contributing to her developmental delays. Despite these concerns, members of her treatment team attributed her lack of progress to the existing hearing loss, providing reassurances that she was “hearing at 35 decibels” with her implants, suggesting that her language issues would improve over time.
Clinical Presentation and Initial Assessment
- Visit to the Specialty Clinic: When the patient visited a specialty clinic for DHH children, clinicians observed several behaviors that raised concerns beyond her hearing impairment. Notably, she exhibited minimal eye contact, limited social engagement, and repetitive behaviors, such as hand flapping, spinning, and circling the room. These behaviors, alongside her lack of expressive language, signaled the possibility of a co-occurring developmental disorder.
- Limited Language Progress: Despite receiving auditory verbal speech therapy and having access to both spoken English and sign language, the patient demonstrated extremely limited language development. She could produce occasional vocalizations and a few spontaneous signs like “want” and “more,” but her expressive language remained far below expectations for her age and hearing status.
Interdisciplinary Evaluation Leads to Autism Diagnosis
Due to the complexity of the patient’s presentation, the clinical team recommended further assessment at the hospital’s autism and developmental disorders clinic. This evaluation involved a range of standardized tests to better understand her developmental profile, including:
- Developmental Profile 3rd Edition (DP-3): Assessed various developmental milestones.
- Childhood Autism Rating Scale, 2nd Edition (CARS2-ST): A tool specifically designed to identify autism traits.
- Brief Observation of Symptoms of Autism—Minimally Verbal (BOSA-MV): Used as a substitute for the Autism Diagnostic Observation Schedule (ADOS) due to COVID-19 restrictions.
- Adaptive Behavior Assessment System, 3rd Edition (ABAS-3): Evaluated her adaptive skills and daily functioning.
Based on the comprehensive evaluation, the patient was diagnosed with Autism Spectrum Disorder in addition to her language disorder. This diagnosis highlighted that her challenges in social interaction, repetitive behaviors, and communication difficulties were not solely attributable to her hearing status.
Challenges of Identifying Autism in Deaf Children
- Overlapping Symptoms: Many of the symptoms associated with autism, such as reduced responsiveness, difficulty with social engagement, and delayed language development, can also manifest in children who are deaf. This overlap can make it challenging for clinicians to distinguish between the impact of hearing loss and the presence of ASD. For example, a lack of eye contact or delayed language skills might be seen as typical for a child adapting to cochlear implants, rather than as indicators of autism.
- Importance of Multidisciplinary Collaboration: This case underscores the necessity of involving professionals across different specialties—such as audiologists, speech therapists, psychologists, and pediatricians—in diagnosing children with complex needs. Collaborative assessments provide a holistic view of the child’s abilities and challenges, reducing the likelihood of overlooking co-occurring conditions like autism.
Impact on Family and Interventions
- Adjustment to Diagnosis: The confirmation of an autism diagnosis was a turning point for the patient’s family. While it was initially difficult for them to accept, it brought a sense of relief, as it provided a clearer understanding of their daughter’s needs and challenges. This shift in perspective allowed the family to adjust their approach, both in terms of daily interactions and the selection of therapeutic interventions.
- Targeted Therapies: Following the diagnosis, the family implemented several recommended interventions, including social skills training, continued speech therapy, and consideration of Augmentative and Assistive Communication (AAC) technologies. The patient was enrolled in a full-time Applied Behavioral Analysis (ABA) program, which proved particularly effective in supporting her development. The family also switched to a speech therapist who had expertise in working with autistic children, leading to better outcomes in her communication skills.
Addressing Diagnostic Overshadowing in Clinical Practice
- Barriers to Accurate Diagnosis: This case study illustrates how cognitive biases, time constraints, and a lack of specialized training can lead to diagnostic overshadowing. When clinicians focus too narrowly on a child’s established diagnosis—such as deafness—they may miss signs of other developmental issues. This is especially true in environments where interdisciplinary communication is limited or undervalued.
- Recognizing Autism in DHH Children: Increased awareness of the distinct presentations of neurotypical DHH children versus those with autism is essential for early and accurate diagnosis. For instance, while both groups might exhibit communication delays, children with ASD often display restricted and repetitive behaviors and may have difficulty forming joint attention or engaging in social play, even when communication supports like sign language are available.
- Unique Needs of DHH Children with Autism: Children who are both deaf and autistic may face unique challenges, such as difficulties tolerating cochlear implants or hearing aids due to sensory sensitivities. Understanding these nuances allows clinicians to differentiate between behaviors related to sensory challenges and those stemming from autism, leading to more tailored interventions.
Conclusion: The Importance of Holistic Evaluation
Diagnostic overshadowing can significantly impact the trajectory of care for children with complex needs, as demonstrated by this case of a delayed autism diagnosis in a deaf child. The case highlights the importance of adopting a holistic, interdisciplinary approach when evaluating children who present with overlapping symptoms. By ensuring that clinicians consider both the sensory and developmental aspects of a child’s condition, it is possible to avoid misdiagnoses and provide timely, effective support.
Ultimately, early recognition of co-occurring conditions like autism in DHH children enables better access to specialized interventions, improving outcomes for the child and providing families with a clearer path forward. The emphasis on collaboration and comprehensive assessment ensures that each child’s unique needs are met, paving the way for their growth and development in both the auditory and social realms.
Source:
https://digitalcommons.usu.edu/cgi/viewcontent.cgi?article=1221&context=jehdi