Describe deafness in children with its causes, screening and habilitation.

Causes and Screening

• Deafness IN childhood matters out of proportion to its prevalence because hearing is the substrate for speech and language.
• A child who does not hear in the first years does not learn to speak, and the consequences are educational, social and lifelong.
• The critical period is the whole point: the auditory cortex requires sound input to develop, and the first 2 to 3 years are decisive for language. Habilitation delayed beyond this is far less effective, however good the technology — which is why the entire subject is about early detection

Assessment and Habilitation

• Age-appropriate testing — otoacoustic emissions and BERA in the newborn; behavioural observation in the first months; distraction testing at 6 to 9 months; visual reinforcement audiometry from 6 months to 2 years; play audiometry from 2 to 4 years; and conventional audiometry thereafter — with tympanometry throughout
• Aetiological work-up — a careful pregnancy, birth and family history including consanguinity; examination for syndromic features; ophthalmology referral (for Usher syndrome, and because a deaf child depends on vision); an ECG for the prolonged QT syndrome; urinalysis for Alport; CMV testing, which must be done on a sample taken within the first 3 weeks or on the stored newborn blood spot, since later testing cannot distinguish congenital from acquired infection; genetic testing including connexin 26; and MRI and CT of the temporal bones
• Habilitation must begin as soon as the diagnosis is made, and is a team effort involving audiologist, speech and language therapist, teacher of the deaf, and the family
• Hearing AIDS — fitted as early as a few weeks of age, bilaterally, with regular re-assessment as the ear grows and the thresholds are refined
• Cochlear implantation for severe to profound bilateral loss with inadequate benefit from aids, ideally before 12 months and certainly before 2 to 3 years; and urgently after meningitis, before the cochlea ossifies
• Speech and language therapy and a chosen communication approach — auditory-verbal, total communication or sign language. The family’s choice must be respected, and there is a genuine Deaf-community perspective that values sign language as a language rather than as a failure of speech
• Educational support — increasingly inclusive schooling with a resource teacher, FM systems and preferential seating, rather than segregated schooling
• Treat the treatable — a coexisting middle ear effusion must be dealt with, since it adds a further conductive loss on top of a sensorineural one and is easily forgotten
• Support the family — the diagnosis is a bereavement for many parents, and counselling, parent groups and clear information determine whether the habilitation is actually carried out
• Under the rights OF persons with disabilities act 2016, hearing disability is certified and confers entitlements to education, aids and reservation, and families should be helped to obtain the certificate
• The first two to three years are decisive for language, which is why the whole subject is about early detection
• Targeted screening misses about half of affected babies, who have no risk factor at all
• Screen by one month, diagnose by three, intervene by six, which is the standard to state and the one that determines outcome
• Emissions alone miss auditory neuropathy, so high-risk babies need automated brainstem response as well
• Connexin 26 is the commonest single genetic cause, and most non-syndromic congenital deafness is autosomal recessive
• Consanguinity substantially raises the risk, which matters particularly in parts of India and should be asked about
• Every deaf child needs an eye examination, for Usher syndrome and because a deaf child depends on vision
• Do an ECG in profound congenital deafness; the prolonged QT of Jervell and Lange-Nielsen causes sudden death
• Test for cytomegalovirus within three weeks or on the stored blood spot; later testing cannot prove congenital infection
• Congenital cytomegalovirus may be silent at birth and cause late-onset progressive loss, so it must be actively sought