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by James W. Thelin and Lori A. Swanson
CHARGE syndrome is a genetic disorder (one in 10,000 to15,000 live births) with multiple physical, sensory, and behavioral anomalies. Children with CHARGE typically undergo 10 surgeries before age 3. Although early mortality rates have been 10% to 20%, survival rates have improved with cardiac treatment. Individuals with CHARGE may have deficits in every sensory modality and frequently exhibit challenging behaviors. CHARGE is presently the leading genetic cause of deaf-blindness at birth in the United States.
For those children who survive the challenges of early life, parents focus their concerns on development, communication, and education. The ultimate level of functioning is significantly enhanced by early intervention from audiologists and speech-language pathologists. In children with CHARGE syndrome, the value of services offered by SLPs and audiologists is enhanced when other aspects of the disorder, such as clinical and genetic diagnosis, feeding and swallowing, behavior, and education, are understood. Information on behavior and development appeared in a 2004 special CHARGE syndrome edition of the American Journal of Medical Genetics.
Ears and Hearing
In CHARGE, every part of the auditory system may be involved. External ear anomalies are so distinctive that, at times, it is possible to make a preliminary diagnosis of the syndrome on the basis of pinna shape alone. (See photos above right and page 7, right.) Middle-ear ossicular anomalies can cause conductive losses as great as 70 dB and chronic otitis media secondary to eustachian tube dysfunction is nearly universal. Underdevelopment of the cochlear and vestibular structures (including Mondini's dysplasia) is common and often causes sensory losses in hearing and balance. Auditory nerve diameter may be reduced; latencies may be prolonged on auditory brainstem response tests; and agenesis of the corpus callosum has been reported. Typical losses are mixed losses with very large conductive components and substantial cochlear involvement that is usually greatest in the high frequencies. The prevalence of severe-profound hearing loss is approximately 50%.
Audiologic evaluation of children with CHARGE is challenging for several reasons:
1) Many children do not speak or sign.
2) Visual problems interfere with sound field audiometry.
3) Tactile defensiveness is common.
4) Hearing losses are often large and asymmetrical.
5) There may be resistance to and risks associated with sedation.
Aural habilitation also can be made difficult by: soft pinnas that do not support hearing aids well, large hearing losses that require tightly fitting earmolds to prevent feedback, and stenosed ear canals with drainage from chronic otitis media.
Selecting and fitting appropriate amplification is often difficult. Some individuals have benefitted from cochlear implants and others from bone-anchored hearing aids.
Despite these challenges associated with multiple physical and sensory deficits, many children with CHARGE who are significantly involved have learned to communicate using symbolic language. Those with the greatest success have had consistent and innovative audiologic intervention very early in life and communication training (spoken and signed language)-even when the child's health was poor and hospitalizations were frequent.
Communication and Related Issues
About 60% of children with CHARGE acquire symbolic language and communicate with spoken language, signs, and/or visual symbols. The mechanics of speech may be affected by craniofacial anomalies, breathing problems, and clefts. Success in acquiring symbolic language is related to communication training begun before age 3, success in overcoming hearing loss, and the ability to walk independently. One explanation for this latter finding is that an ambulatory child has the ability to move into his or her own communication bubble-the space in which the child can see and hear a communication partner optimally. Among children who use symbolic language, however, speech and language problems are common. Children who use symbolic forms often have problems in maintaining a topic and in effective turn-taking.
Children who do not acquire symbolic language may learn to demonstrate higher forms of prelinguistic communication such as use of gestures and vocalizations to regulate the behavior of others. Those who are most impaired may produce pre-intentional behaviors, which parents and caregivers may interpret as intentional. Since children with CHARGE often demonstrate a high rate of repetitive behaviors, parents and caregivers may have difficulty assigning meaning to potential communication acts.
Adapted Prelinguistic Milieu Teaching (PMT, Warren & Yoder, 2002) is currently being tested as a means to increase the rate and variety of prelinguistic communications in the deaf-blind population by Bashinski and Brady at the University of Kansas. PMT focuses on increasing use of gestural forms (e.g., distal points, gives, shows, and leading gestures), increasing rate of communication, and improving parent responsivity, which appear to be predictors of increased communication skills in children with disabilities (Brady, Marquis, Fleming, & McLean, 2004). Gestures may have some advantages over symbolic forms of communication. Unlike signs, they are readily understood by most communication partners. Most importantly, gestures may facilitate understanding of the give and take between people that underlies communication.
Children with CHARGE often also have feeding and swallowing difficulties, behavior problems unique to the syndrome, and very special educational needs. Before CHARGE was recognized as a unique disorder, individuals with the disorder were believed to have a collection of unrelated anomalies. They received treatment from many specialists that was not coordinated. Now that CHARGE is recognized, it is clear that optimal treatment results from the collaboration of specialists in medicine, communication, behavior, and education.
Problems related to CHARGE often are inter-related, and communication is an essential part of an effective clinical response. As an example, investigators at the University of Tennessee asked parents how the communication of their child with CHARGE was affected by their child's behavior. The parents responded that in many cases an inability to communicate was the cause of inappropriate behavior.
Emerging evidence suggests that early intervention by speech-language pathologists, audiologists, and educators of the deaf can enhance the acquisition of symbolic language that is crucial to communication development, social interaction, and learning. Early and persistent intervention for speech, language, swallowing, and hearing disorders can greatly enhance the quality of life for children with CHARGE syndrome-even for those who have frequent illness and those who are severely involved. An increased awareness of CHARGE syndrome should lead to enhanced services provided by professionals in our field.
James W. Thelin is an associate professor in the Department of Audiology and Speech Pathology at the University of Tennessee, Knoxville (UTK). Contact him at jthelin@utk.edu.
Lori A. Swanson is an associate professor in the Department of Audiology and Speech Pathology at UTK. Contact her at lswanson@utk.edu.
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