Literature Review
The establishment and maintenance of programs TAN have aroused interest and concern
of audiologists, otolaryngologists and pediatricians, given the importance of ensuring
early diagnosis and intervention of hearing loss[1].
In developing countries, the Newborn Hearing Screening Program (NHSP) have been conducted
since 1986, with India the pioneer (in neonates at risk). Oman was the first country
with nationwide NASP and Iran are in pilot studies 28 of 30 provinces. In Singapore
the TAN has been performed in immunization clinics. The procedure was rejected by
59% of the families of children aged four months or less[2].
Study Masoud et al. (2006) reports that in developing countries that Brazil is the largest number
of services that provide NAS (237 sites)[3]. One hundred and thirty-seven institutions, including hospitals and clinics are
registered with the Support Group Universal Newborn Hearing Screening (GATANU). The
southeast region, comprising the states of Sao Paulo, Rio de Janeiro, Espirito Santo
and Minas Gerais, it shows a greater number of programs TAN (63 services), followed
by southern region comprises the states of Rio Grande do Sul, Santa Catarina and Paraná
(34 services). The northern region (Acre, Amapá, Amazonas, Rondônia, Roraima, Para
and Tocantins), it shows the lowest number of programs registered with GATANU, four
in hospitals and in private practice[4].
In Brazil, the first programs of TAN was established in 1987, one in São Paulo Hospital
(São Paulo, SP) another at the University Hospital of Santa Maria (Santa Maria). The
procedure used in both institutions was the observation of responses behavior[5].
The following year, the Hospital Israelita Albert Einstein, started the first program
of TAN that used electrophysiological method (Potential Auditory Brainstem Response
- ABR) and had speech pathologist in the neonatal team. Initially covered only neonates
with risk factors for deafness, but gradually expanded to all children in the Neonatal
Intensive Care Unit (NICU).From 1999 the assessment of evoked otoacoustic emissions
(SOAE) was being used[6].
In Europe, TAN programs involve the whole continent, and now cover more than 90% of
Austria, Belgium (Flemish part), Denmark, Croatia, England, Luxembourg, the Netherlands
and Poland. A partial implementation has been made in Germany, Italy, Lithuania, Malta,
Spain, Sweden, Switzerland and Wales. Already the French part of Belgium, Cyprus,
France and Ireland are in advanced stage, while the Czech Republic, Estonia, Finland,
Greece, Hungary, Latvia, Norway, Portugal, Romania, Scotland, Slovakia, Slovenia and
Turkey are in pilot phase[7].
The NASP TRIAM England around 1700 children every day and are recognized as the most
advanced in the world. More than 3400 children with hearing loss have been identified[8].
In setting standards for programs TAN American Academy of Pediatrics (AAP, 1999)[9] suggested that they were universal, false-positive rate of less than or equal to
3%, the referrals to the stage of diagnosis did not exceed 4% and the procedures used
were SOAE and / or ABR. Still, the NHS should be performed before discharge, between
the first 24 and 48 hours of life.In case of failure, the retest should be performed
within a month. The diagnosis should be completed before three months of life and
intervention begun before six. TAN programs should be evaluated according to the rules
of the AAP (1999).
The NHS has a universal character when they are screened at least 95% of newborns
(AAP, 1999). There are reports of Universal Newborn Hearing Screening (UNHS) in Mexico
(Monterrey)[10], Spain (Cantabria)[11], Germany (Hamburg)[12], United States (USA) (states with implemented legislation[13], State of Mississippi[14], New Mexico[15], France (Eure)[16], Norway (County Ostfold)[17], public hospitals in Singapore[2], Western Australia (Perth)[18], Nigeria[19]
[20], South Africa[21] and Hong Kong[22].
The acceptable rates of false-positive according to the AAP (1999) is equal to or
less than 3%. The countries that met this criterion were Mexico[10] and USA[23].
The rate of referral to diagnosis was less than 4% (AAP, 1999) Brazil[24], Norway (County Ostfold)[17], Saudi Arabia[25], Nigeria[20], Slovakia (Limbova)[26], Oman[27], Singapore[28] and Mexico[10].
The procedures set forth by the AAP (1999) are SOAE and / or ABR. The most commonly
used in programs for the NHS in different countries are presented in [Tables 1], [2], [3] and [4].
Table 1.
Institutions, municipalities / cities and states or countries that employ only SOAE
in the implementation of the NHS.
|
Country
|
County / State or Location
|
Institution
|
|
South Africa[29]
|
Pretoria / Gauteng
|
NC
|
|
Germany[12]
|
Hamburg
|
Marien Hospital
|
|
Saudi Arabia[25]
|
NC
|
NC
|
|
Austria[30]
|
NC
|
NC
|
|
Brazil[24]
|
Sao Paulo / SP
|
Hospital Israelita Albert Einstein
|
|
Slovakia[26]
|
Limbova
|
Children's University Hospital
|
|
Spain[31]
|
Gijón / Asturias
|
Hospital Cabueñes
|
|
Philippines[32]
|
Manila
|
Philippine General Hospital
|
|
Greece[33]
|
Athens
|
Hippokration Hospital
|
|
Italy[34]
|
Rome
|
CN
|
|
Iran[3]
|
Tehran, Mashad
|
NC
|
|
Pakistan[35]
|
Lahore
|
NC
|
|
Poland
|
Poznan[36]
|
Hospital of the University of Poznan
|
|
Zabrze[37]
|
Silesian Medical Academy
|
|
Qatar[38]
|
Doha
|
NC
|
Table 2.
Institutions, city / states or localities and countries using SOAE in the NHS and
in case of failure or RN's with risk factors for hearing loss, evaluate ABR for diagnosis.
|
Country
|
County / State or Location
|
Institution
|
|
Spain
|
Cantabria[11]
|
NC
|
|
Valladolid[39]
|
Hospital Universitario de Valladolid
|
|
France[16]
|
Eure
|
Eure Geographic Department
|
|
Israel[40]
|
NC
|
NC
|
|
Italy[41]
|
Milan
|
NC *
|
|
Jordan[42]
|
NC
|
NC
|
|
Malásia[42]
|
Kuala Lumpur
|
Hospital Universitário de Kebangsaan Malásia
|
|
Taiwan[43]
|
NC
|
Mackay Memorial Hospital
|
* Institution that has implemented TAN, UO Neurologia, Dipartimento di neuropathophysiology
and Neonatology Clinic of the Istituti di Perfezionamento. SOAE: Evoked Otoacoustic
Emissions; TAN: Newborn Hearing Screening; NB: newborn; ABR: Auditory Evoked Potential
Brain Stem, NC: Not applicable information cited in the study.
Table 3.
Institutions, cities / states or localities and countries using SOAE in the NHS, and
in case of failure, AABR.
|
Country
|
County / State or Location
|
Institution
|
|
England[44]
|
NC
|
NC
|
|
Norway[17]
|
Ostfold County,
|
NC
|
|
Oman[27]
|
NC
|
NC
|
SOAE: Evoked Otoacoustic Emissions; TAN: Newborn Hearing Screening; AABR: Automated
Auditory Brainstem Response (Automatic Response Auditory Brainstem Response) NC: Not
applicable information cited in the study.
Table 4.
Institutions, cities / states or localities and countries using SOAE and / or AABR
in implementing the NHS.
|
Country
|
County / State or Location
|
Institution
|
|
China[45]
|
Shanghai, Bijing, Shandong
|
CN
|
|
Hong Kong[46]
|
Hong Kong
|
CN
|
|
Nigeria[19]
[20]
|
Lagos
|
NC
|
|
Singapore[2]
|
Singapore
|
NC
|
SOAE: Evoked Otoacoustic Emissions; TAN: Newborn Hearing Screening; AABR: Automated
Auditory Brainstem Response (Automatic Response Auditory Brainstem Response) NC: Not
applicable information cited in the study.
In addition to the procedures set out in [Tables 1], [2], [3] and [4], Mexico (Monterrey)[10] NAS was performed using the Automatic Response Auditory Brainstem Response (Automated
Auditory Brainstem Response - AABR) and failure mode was performed ABR. South Africa[21] was used to EOAEPDs associated with high frequency tympanometry and Limbova (Slovakia)[47] was used to search the EOAETs and in case of failure, the performance of tympanometry.
Norway (Oslo)[48] and Australia (Perth)[18] the use of SOAE AABR was associated in all stages of screening. In the states of
Mississippi[14] and NC (USA)[23] to screening was performed only with ABR. In a study conducted from March 2000 to
December 2002 in Taiwan[49] newborns were screened with SOAE associated with ABR.
According to the AAP (1999), the NHS must be held between the first 24 and 48 hours
of life. [Table 5] shows the ages in which the NHS is carried out in different countries.
Table 5.
Countries / Institutions that mentioned the age at which the NHS was carried out.
|
Country / Institution
|
Age at attainment of Hearing Screening
|
|
Brazil / Hospital Israelita Albert Einstein[24]
|
Second or third day after birth or before discharge for newborns admitted to NICU.
|
|
Spain / Hospital Cabueñes[31]
|
Median age of 71 days
|
|
Spain / University Hospital of Valladolid[39]
|
Less than six months
|
|
Greece / NC[33]
|
More than 36 weeks
|
|
Italy / NC
|
36 hours after birth (Milan)[41]
|
|
Italy / CN
|
Second or third day of life (Rome)[34]
|
|
Nigeria / NC[20]
|
Average age of 2.6 months
|
|
Norway / NC[17]
|
Second day of stay in nursery
|
|
Poland / Poznan University Hospital[36]
|
Second or third day of life
|
|
Taiwan / Mackay Memorial Hospital[43]
|
Average age of 52.
|
NB: Newborn; NICU: Neonatal Intensive Care Unit; NC: Not applicable information cited
in the study.
Brazil[24], Italy (Rome[34] and Milan[41]) and Poland[36] (Hospital of the University of Poznan) all children were screened at the recommended
period.
The AAP (1999) also notes that the NHS should be performed before hospital discharge.
Publications that provide such information only in Malaysia (Hospital Universiti Kebangsaan Malaysia)
[42]) and South Africa (Gauteng)[29] NAS did not follow the norm of the AAP.
In case of failure in the NHS, the retest must be completed within one month after
the first screening (AAP, 1999). This approach was adopted in Brazil (Sao Paulo)[24], Italy (Milan)[41] and France (Eure)[16]. Malaysia (Hospital Universiti Kebangsaan Malaysia)
[42] children were retested at two and, if the new fault, after three months, and in
South Africa (Gauteng)[29] and second test was performed six weeks after failing to first hearing screening.
Publications from ten countries cited the time of completion of stage of diagnosis:
USA (Colorado[50]
[51] Mississippi[14]), Spain (Cantabria)[11], Italy (Sicily)[52], Austria[30]
[53] Germany[7]
[54], Singapore[2] Saudi Arabia[25], Nigeria[20], South Africa[55] and Mexico (Monterrey)[10]. The diagnosis was made within the period recommended by 100% of the cases only
in Monterrey (Mexico)[10]. In the state of Colorado (USA)[51], from 1992 to 1999 the diagnosis was done before 3 months in 71% of newborns screened.
Nigeria[20] the age at diagnosis ranged from 46 to 360 days. In other countries the average
age of diagnosis ranged between 3.9 months (Mississippi / USA)[14] and 39 months (Germany)[54].
USA[50], Austria[53] and Germany[54] the age of identification of hearing impairment in children not screened was higher
than those who carried out the NHS. Colorado (USA)[50] the diagnosis was made, albeit belatedly, before six months in 84% of children subjected
to TAN and only 8% of children not screened. In Austria[53] and Germany[54] the children who did not undergo the NHS had hearing loss diagnosed on average at
37.6 and 17.8 months respectively. Have the children screened were diagnosed to complete
3.9 (Austria[53]) and 3.1 months of age (Germany[54]).
According to the AAP (1999) and the Joint Committee on Infant Hearing (JCIH) (2007)[56] the intervention should be started before six months of age. Publications that reported
the time it was made the contribution, the suggested course of action was adopted
only in Italy (Sicily)[52] and Austria[53] in children who carried out the NHS. In another publication from that country[30], 1990-2006, 61% of children screened were referred to appropriate intervention by
six months, versus only 4% of children who did not attend the NHS. Germany[54] age of children screened at the time of intervention had a median of 3.5 months
and screened children do not age at diagnosis had a median of 21 months.
Spain (Cantabria)[11] only 50% of the children began treatment before six months. Mexico (Monterrey)[10], although 100% of diagnoses are made within this period, all children diagnosed
after the intervention had six months of age. Cuba[57] the intervention started on average at 10 months of age in Singapore[2] to 42.4 months and the state of Mississippi (USA)[14] to 6.1 months.
In Brazil there are laws making it mandatory in the NHS states of Paraná, Pernambuco
and Sao Paulo[5], Santa Catarina, Minas Gerais, Piauí, Rondônia and Mato Grosso do Sul[58]. The bill (the federal) No 697/07 (in progress), provides for the compulsory examination
Evoked Otoacoustic Emissions - OAE “, known as” the OAE test “for all newborns in
the country[58].
In Germany, there are legislative efforts to deploy a TANU as regular procedure offered
to all newborns[7].
United States (U.S.) states where TAN is required by law, according to the Centers for Disease Control and Prevention (2007)[59], are Arkansas, California, Colorado, Connecticut, Florida, Georgia, Hawaii, Illinois,
Indiana, Iowa, Kansas, Kentucky, Louisiana, Maine, Maryland, Massachusetts, Mississippi,
Missouri, Montana, Nebraska, Nevada, New Hampshire, New Jersey. New York, North Carolina,
Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, Texas, Utah, Virginia,
West Virginia, Wisconsin and Wyomin.
As noted by Green et al. (2007)[13] in the USA the rate of completion of NHSP in states that have legislation is higher
than the others. Triaram states that 95% of newborns were mostly those with implementing
legislation.
Discussion
A growing number of countries aware of the necessity of implementing programs TAN.
These programs will significantly increase the rate of early diagnosis of hearing
loss in children and are being implemented efficiently and effectively in various
locations.
TAN programs are being implemented as part of health systems in about 55 countries,
where the search for improvements is increasing. In countries where TAN is not yet
implemented, is an arduous struggle for its implementation.
The implementation of programs for the NHS both in developed countries as in developing
bumps into obstacles such as lack of suitable environment for the testing, few professionals
and prepared for such a task, lack of professionals who undertake the TAN at the end
of week, lack of services for monitoring and control, and especially, little information
about the benefits provided to deaf children[60], both by professionals and the general population. This complicates the process
of universalization of TAN and leads to a large number of dropouts before completion
of all steps necessary[44].
It is necessary to carry out awareness programs about the importance of newborn hearing
screening and the benefits provided by this program.
One of the main consequences of the lack of legislation in favor of NAS is the late
diagnosis of hearing loss in children and the low rate of children screened. The age
of identification of hearing impairment in children not screened is higher than that
of children who underwent TAN[50]
[53]
[54]. Due to this, many countries are making efforts to adopt and implement laws to implement
the NHS and thereby ensure that all children have their hearing tested in a timely
fashion.
The universal and binding of the NHS has been highlighted extensively, so that no
child with a hearing disability ceases to be diagnosed and receive the assistance
necessary for an adequate social, psychological, educational and linguistic. Yet it
was observed that despite the recommendations of the AAP (1999) and JCIH (2007), there
are many programs that practice selective hearing screening.
It was found that the NHS is being applied in some places, after the third month of
life, which delays diagnosis and intervention.
The procedures most frequently used are common to developed and developing countries.
The most widely used procedure in the NHS has been examining SOAE. In case of failure
the most frequent is the retest with SOAE and only in the event of another failure,
children are referred for evaluation of diagnostic ABR or AABR. What proved to be
highly variable across studies was the time set for the children who failed the screening
return for retest. This time ranged from seven days (Santa Maria / Brazil) to two
months (Malaysia)[54].
The NHS has proved a highly effective and feasible procedure. Its relevance lies in
the reduction in children's age at diagnosis and intervention, especially in places
filled legislation.
Thus, the path seems to be the search for improvements in existing programs, implementing
new programs and legislation of laws that support you.
