Hearing loss can be defined as conductive or sensorineural. Conductive hearing loss occurs due to dysfunction of the outer or middle ear, which prevents transmission of sound waves from reaching the inner ear. Sensorineural hearing loss, on the other hand, is the result of inner ear or auditory nerve dysfunction preventing neuronal transmission to the brain. In developed countries, approximately 1/1,000 children have severe or profound hearing loss at birth or during childhood. In most cases, hearing loss is a multifactorial disorder caused by genetic and environmental factors. Clinically, it has many different presentations, from mild to profound, including low and high-pitch patterns. Non-syndromic forms are responsible for about 70% of the cases of hereditary etiology and syndromic cases represent 30% of them. Among the patterns of inheritance, autosomal recessive remains the most common form of inheritance, although it can be autosomal dominant, X-linked or mitochondrial.
The Igenomix Syndromic and Nonsyndromic Deafness Precision Panel can be used to make an accurate and directed diagnosis as well as a differential diagnosis of hearing loss ultimately leading to a better management and prognosis of the disease. It provides a comprehensive analysis of the genes involved in this disease using next-generation sequencing (NGS) to fully understand the spectrum of relevant genes involved.
- The Igenomix Syndromic and Nonsyndromic Deafness Precision Panel is indicated for those patients with a clinical suspicion or diagnosis with or without the following manifestations:
- Difficulty understanding words
- Muffling of speech and other sounds
- Trouble hearing consonants
- Needing to turn up the volume of the television or radio
- Associated syndromic features at birth: cardiac findings, renal findings, neurologic abnormalities, skeletal examination findings, craniofacial abnormalities etc
- Withdrawal from conversations
- Avoidance from social settings
The clinical utility of this panel is:
- The genetic and molecular confirmation for an accurate clinical diagnosis of a symptomatic patient.
- Early initiation of treatment with a multidisciplinary team in the form surgical care of external and middle ear deformities, cochlear implantation and medical care for treatment of middle ear disease, amplification and assistive listening devices.
- Early implementation of speech and language therapy.
- Risk assessment and genetic counselling of asymptomatic family members due to the autosomal dominant mode of inheritance.
- Improvement of delineation of genotype-phenotype correlation.
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