Considerations in the Management of Functional Neurological Disorders in Patients with Hearing Loss

Abstract

CASE: Adam is a 14-year-old adolescent boy with hearing loss who presented to the pediatric neurology clinic accompanied by his father for evaluation of new-onset left hand tremor for a duration of 1 month. An American Sign Language interpreter was present and used throughout the visit. Adam has bilateral sensorineural hearing loss related to premature birth at 28 weeks' gestation. He uses sign language and attends a school for the hearing impaired. He has been diagnosed with attention-deficit/hyperactivity disorder (ADHD) and a nonspecific learning disorder. His ADHD symptoms are well controlled with a stimulant medication. He is independent in activities of daily living, and there is no concern for intellectual disability. His father is concerned that Adam may have anxiety, but this has not been evaluated. After careful history, it is found that the tremor was first noted the day after burglars broke into his home and stole precious belongings. Current stressors include difficulties with schoolwork and a strained relationship with an extended family member. There is no family history of tremor. The tremor was intermittent initially, with episodes lasting around 30 minutes. Over time, the tremor became more persistent. Adam is left-handed, and the tremor is now interfering with handwriting, eating, and other fine motor skills. The tremor worsens when Adam is tired or stressed and improves with relaxation. No tremor has been noted in other body parts. Adam denies any other neurological symptoms, including headache, vision changes, or gait abnormalities. On examination, Adam seemed anxious but showed no significant distress and had normal vital signs. His general examination was unremarkable. His neurological examination showed intact cranial nerves, apart from the hearing impairment. He had normal muscle tone, intact strength and coordination, and a normal casual gait. Rhythmic shaking of the left upper extremity was present with action, while maintaining posture. Using specific examination techniques, the examiner was able to alter the rhythm of the tremor, and the tremor was noted to subside when the patient was engaged with the examiner. These findings in addition to signs of suggestibility and variable frequency/direction were consistent with a functional etiology. The diagnosis of a functional neurological disorder manifesting in the form of functional tremor was discussed with the patient and his father with assistance from the sign language interpreter. Counseling regarding management consisting mainly of cognitive behavioral therapy and evaluation of possible coexisting conditions, such as anxiety, was discussed. What factors would you consider in diagnosis and management of functional neurological disorder in a hearing-impaired child/adolescent?