August 25, 2022 For every 1000 newborns, one to two healthy children are born deaf. Universal neonatal hearing screening is an important tool for the diagnosis of deafness at birth and all newborns should do it. Early diagnosis of deafness in children is essential. When left untreated, deafness can have serious consequences on children speech and language development and, as such, on their communication skills. This could be decisive for their school performance and psychosocial development, and could influence their entire future. When to suspect deafness As a child grows, deafness should be suspected when there are signs that language does not develop according to what is expected for the age, for example: Does not react to sounds, does not look for sound or does not smile until 6 months of age; Does not produce sounds, does not chat, does not react to its name until 1 year of age; Does not say simple words like mom, dad, yes, no among others, up to 15-18 months of age; Does not understand simple instructions, does not build simple sentences with 2 up to 2 years of age. Sentences should increase in complexity over the 2 years; Speech is not understood and uses more gestures than words between 3 and 4 years of age; Speaks within what was expected for age, but stopped speaking or regressed. The diagnosis of deafness in children is not always easy. A high index of suspicion is needed both by parents and caregivers and in the school environment (in day care and school). Types of deafness There are two types of deafness. Transmission deafness In transmission deafness, there is a compromise in the transmission of sound . The cause can be a cerumen plug, serous otitis, middle ear and ear ossicle problems, among others. Serous otitis is the most frequent cause of transmission deafness in preschool age and is related to the presence of mucus/fluid in the middle ear (not related to the presence of ear wax) preventing normal sound transmission. In addition to causing deafness, serous otitis can lead to recurrent otitis and, if left untreated, can progress to chronic otitis. Generally, transmission deafness has treatment , either medical and/or surgical. Sensorineural deafness In sensorineural deafness there is a compromise in the perception of sound . Sensorineural deafness is irreversible and permanent . It can be congenital , when children are already born with deafness, or acquired , when it is later, appearing after birth. Congenital sensorineural deafness Congenital sensorineural deafness can be hereditary or be related to changes that occurred in utero during pregnancy. The existence of family members with a history of congenital deafness should alert to the possibility that it is a hereditary deafness of genetic cause that corresponds to more than 50% of cases of congenital deafness. Regarding its transmission, hereditary deafness can have the following behaviors: Autosomal dominant and, in this case, one of the parents is also deaf; Autosomal recessive and, in this case, there are relatives with a history of deafness in the family, but the parents do not have deafness; X-linked and in this case the mother carries the gene and does not have deafness, but her male children will be born deaf. In utero , during pregnancy , infections or changes associated with the development of deafness in the baby can also occur. This is the case with rubella, toxoplasmosis, syphilis, cytomegalovirus or herpes simplex virus infection. Acquired sensorineural deafness During delivery and in the immediate peripartum period , complications can occur that can lead to deafness in the newborn. Examples are neonatal asphyxia, prematurity, need for ototoxic drugs, hyperbilirubinemia with kernicterus, among others. Meningitis, encephalitis, measles, mumps, are examples of infectious diseases that can lead to acquired sensorineural deafness. There are also several syndromes that within their manifestations also occur with deafness. Examples of genetic syndromes such as Down, Usher, Treacher Collins, Crouzon, Alport, among others. Depending on its severity, sensorineural deafness may require auditory rehabilitation with a hearing aid or, in cases of profound deafness, the placement of a cochlear implant . When to see an otolaryngologist Any child with suspected deafness should be referred as soon as possible to an otorhinolaryngology or infantile deafness consultation. Depending on child age, diagnostic tests such as pediatric audiometry, tympanogram or impedancemetry, otoacoustic emissions, brainstem auditory evoked potentials and imaging tests may be ordered by the otorhinolaryngologist for the diagnosis of deafness. The earlier the diagnosis, the faster the medical and/or surgical intervention in order to reduce the future consequences for the child. This article was written by the Hospital da Luz otorhinolaryngology team. The content published in the Health Guide is intended for the general public and is provided for informational and educational purposes only. It does not replace individual medical assessment, diagnosis, or personalized clinical advice from a qualified healthcare professional. The content is produced or reviewed by physicians and other healthcare professionals at Hospital da Luz and is based on the knowledge available at the time of publication or the most recent update, as indicated at the beginning of each item.
