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N. Türe et al.
membrane—into the region of the middle ear. It may be present from birth or
acquired later. It generally causes conductive hearing loss through direct impingement on the ossicles or by eroding the ossicles. Cholesteatoma occurs as a primary
condition after birth and begins with tympanic membrane retraction. This is typically the result of eustachian tube malfunction. Sinus cholesteatoma affects the posterior aspect of the pars tensa whilst the more common attic cholesteatoma affects
the pars accida. The portion of the tympanic membrane where retraction occurs
forms a pocket with a lining composed of normal stratied squamous epithelium
and lled with keratin sloughed by desquamated cells. Secondary acquired cholesteatoma occurs following the perforation of the tympanic membrane if the epithelium regrows in the wrong direction (i.e. into the middle ear, rather than closing off
the defect) [1].
The main objective of operative intervention is to clean and dry the ear, leaving
it safe from further disease arising from recurrence or as a result of parts of the
cholesteatoma remaining in situ. The condition recurs more commonly in paediatric
than adult cases, which may be due to the fact the eustachian tubes are still developing in a child. The other objective is to remedy any CHL resulting from the condition. To achieve this, the reconstruction of the ossicles may be needed, either at the
time of cholesteatoma removal or subsequently. A conventional hearing aid may
help, as may a bone conduction device; consideration should also be given to educational accommodations, including an FM system and preferential seating [1].
1.4 Conclusion
Paediatric hearing loss may be congenital or acquired, sensorineural or conductive.
While sensorineural loss is more common in pure congenital hearing loss, the most
common cause of hearing loss in the general paediatric population remains otitis
media with effusion. Individual patient factors dictate differences in diagnostic and
therapeutic approaches.
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16. Hartel BP, van Nierop JWI, Huinck WJ, Rotteveel LJC, Mylanus EAM, Snik AF, et al.
Cochlear implantation in patients with Usher Syndrome type IIa increases performance and
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18. Koyama H, Kashio A, Sakata A, et al. The hearing outcomes of Cochlear implantation in
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26. Dostal A, Nemeckova J, Gaillyova R, et. al. Identication of 2.3-Mb gene locus for congenital
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28. Broen PA, Moller KT, Carlstrom J, et. al. Comparison of the hearing histories of children with
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29. Sheahan P, Blayney AW, Sheahan JN, et. al. Sequelae of otitis media with effusion among
children with cleft lip and/or cleft palate. Clin Otolaryngol Allied Sci. 2002;27:494–500.
30. Flynn T, Moller C, Jonsson R, etal. The high prevalence of otitis media with effusion in children
with cleft lip and palate as compared to children without clefts. Int J Pediatr Otorhinolaryngol.
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31. Friedman RA, Kesser BW, Derebery JM. Surgery of ventilation and mucosal disease. In:
Brackman DE, Shelton C, Arriaga MA, editors. Otologic surgery. Philadelphia: Elsevier;
2010. p.73–91.
32. Fiellau-Nikolajsen M.Epidemiology of secretory otitis media. A descriptive cohort study. Ann
Otol Rhinol Laryngol. 1983;92:172–7.
33. Mehta RP, Rosowski JJ, Voss SE, et al. Determinants of hearing loss in perforations of the
tympanic membrane. Otol Neurotol. 2006;27:136–43.
34. James AL, Papsin BC.Ten top considerations in pediatric tympanoplasty. Otolaryngol Head
Neck Surg. 2012;147:992–8.
35. Hardman J, Muzaffar J, Nankivell P, et. al. Tympanoplasty for chronic tympanic membrane
perforation in children: systematic review and meta-analysis. Otol Neurotol. 2015;36:796–804.
36. Duval M, Grimmer JF, Meier J, etal. The effect of age on pediatric tympanoplasty outcomes:
a comparison of preschool and older children. Int J Pediatr Otorhinolaryngol. 2015;79:336–41.
37. Gross CW, Bassila M, Lazar RH, etal. Adipose plug myringoplasty: an alternative to formal
myringoplasty techniques in children. Otolaryngol Head Neck Surg. 1989;101:617–20.
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N. Türe et al.
Newborn Hearing Screening
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RecepKaramert, AylaGünlemez, andStephanLang
2.1 Introduction
Congenital hearing loss (HL) is the most common congenital disability. According
to the World Health Organization (WHO), the estimated prevalence of disabling HL
in the neonatal period is 2 per 1000 live births [1]. Hearing loss in infancy has a
marked negative impact on developing communication skills and achieving good
academic and social performance. Even mild losses yield delayed speech and language development [2]. Time is crucial in managing the diagnosis and rehabilitation
of HL in infancy. If early access to rehabilitation is provided, infants with hearing
impairment may achieve comparable speech and language development with their
normal hearing peers. Such performance is less likely in infants diagnosed with HL
after the rst 6months of life due to missing the critical period for the maturation of
the central auditory pathway [3, 4].
2
R. Karamert (*)
Department of Otorhinolaryngology, Faculty of Medicine, Gazi University, Ankara, Türkiye
e-mail: recepkaramert@gazi.edu.tr
A. Günlemez
Division of Neonatology, Department of Pediatrics, Faculty of Medicine, Kocaeli University,
Kocaeli, Türkiye
e-mail: aylagunlemez@yahoo.com
S. Lang
Department of Otorhinolaryngology, Head and Neck Surgery, University Hospital Essen,
Essen, Germany
e-mail: stephan.lang@uk-essen.de
© The Author(s), under exclusive license to Springer Nature
Switzerland AG 2023
A. E. Arısoy et al. (eds.), Hearing Loss in Congenital, Neonatal and Childhood
Infections, Comprehensive ENT, https://doi.org/10.1007/978-3-031-38495-0_2
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Awareness of the positive impact of early diagnosis and prompt intervention on
congenital HL dates back to the 1940s [5]. But establishing the rst universal
screening program took several decades because of the lack of feasible screening
methods. After the introduction and widespread use of objective physiologic screening tests like automated otoacoustic emissions (A-OAEs) and automated auditory
brainstem response (A-ABR), universal newborn hearing screening (NHS) programs gradually spread worldwide [6–8]. Newborn hearing screening has provided
a denite advantage in detecting HL compared to previous methods, such as behavioral or risk-targeted screening [9–11].
The mean time interval for the diagnosis of congenital HL is 4.6months, and the
mean time interval for the rst intervention is 6.7months in very highly developed
countries for infants enrolled in an NHS program. On the contrary, the mean time
intervals for diagnosis and rst intervention are 34.9months and 36.7 months in
unscreened infants [11]. As a consequence, NHS has become a routine of the
national healthcare system in many countries in the new millennium, but overall
global access to NHS is still limited. A recent survey showed that 38% of newborns
are born in countries with less than 1% NHS coverage [12].
Screening is the initial effort for the early diagnosis and remediation of congenital HL.Further steps require strong participation of the families and interdisciplinary collaboration among medical professionals like otorhinolaryngologists,
audiologists, and pediatricians. According to Holte etal. [13], only one-third of
the infants who failed the initial screening receive a timely diagnosis and enroll in
an early intervention program. Therefore, the NHS system should be family-centered to avoid follow-up loss and encourage the family members to maintain the
diagnostic and remediation procedure. It should be emphasized that passing the
screening tests does not mean that the hearing threshold of the infant is within
normal limits.
Current audiologic screening tests may miss mild (thresholds under approximately 35–40 deciBel [dB]) or neural HL, and progressive or delayed-onset HLs
are still cause for concern, particularly in infants who have specic risk factors
[14]. As the incidence of disabling HL in school-age is twice as high as in the
neonatal period, ongoing surveillance of auditory perception and communication
skills should be mandatory in all children [15]. Risk factors for progressive or
delayed- onset HL are listed in Table2.1 [14, 16–18]. Infants who meet any highrisk criterion must receive a meticulous audiologic evaluation in the rst 9months
of age [14].
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Table 2.1 Risk factors for progressive or delayed-onset hearing loss
Perinatal
1. Family history of deafness with onset in childhood
2. The neonatal intensive care unit stay longer than 5days
3. Mechanical ventilation
4. Hyperbilirubinemia requiring exchange transfusion
5. Perinatal asphyxia and/or hypoxic–ischemic encephalopathy
6. Extracorporeal membrane oxygenation (ECMO)
7. In-utero infections: Cytomegalovirus, rubella, toxoplasmosis, syphilis, herpes, human
immunodeciency virus, Zika virus
8. Craniofacial and physical conditions related to hearing loss
9. Very low birth weight (<1500g)
10. Maternal substance use disorder
11. Syndromes related to hearing loss
Perinatal or Postnatal
1. Ototoxic medications: aminoglycosides, diuretics
2. Meningitis or encephalitis
3. Head trauma
4. Suspicion of hearing loss and related abnormalities noticed by family or caregiver
a
Adapted and modied from Ref. [14, 16–18]
a
2.2 Etiology
2.2.1 Prenatal Period
2.2.1.1 Genetic Factors
Hearing loss is genetic in origin in more than 50% of neonates [19]. Hereditary HL
may accompany other disorders like visual impairment, endocrinologic and neurologic pathologies as a part of a syndrome, or present as isolated defects. More than
250 genes are associated with hereditary HL [1]. Inheritance of the genetic HL may
be in autosomal recessive (AR), autosomal dominant (AD), X-linked (XL), or mitochondrial manner.
Consanguineous marriages increase the risk of congenital diseases, as well as
HL [20], and linguistic homogamy (intermarriage between deaf individuals) has an
essential role in the increased prevalence of recessive mutations in connexin 26
genes [21]. Genetic counseling and testing are recommended for all infants with
HL [22].
Syndromic Hearing Loss
Over 400 identied syndromes exist associated with HL [23]. Of these, Pendred
syndrome, related to the solute carrier family 26 member 4 (SLC26A4) gene mutations in both alleles and inherited in an AR manner, with a due of 10% seems to be
the most common reason for syndromic HL [6, 24, 25]. The SLC26A4 gene provides instructions for making a protein called pendrin which transports negatively
charged particles (ions), including chloride, iodide, and bicarbonate, across cell
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membranes. Pendrin is produced in several organs and tissues, particularly the thyroid gland and inner ear.
Pendred syndrome is characterized by goiter, sensorineural HL (SNHL), and an
enlarged vestibular aqueduct (EVA). Goiter may not be apparent until adolescence,
and HL may be late-onset. Thus, the diagnosis of Pendred syndrome may be
delayed. There appears to be a relationship between the most common inner ear
malformation EVA and SLC26A4 mutation [24]. Apart from Pendred syndrome,
61% of nonsyndromic patients with EVA also carry a heterozygous SLC26A4
mutation [25].
Usher syndrome is characterized by retinitis pigmentosa, SNHL, and in some
forms, vestibular symptoms. Usher syndrome is the most common cause of deafness and blindness combination. Impairment in hearing and visual functions yields
specic limitations in communication skills, so early intervention for HL is critical
to maintain auditory perception and speech and language development.
Biotinidase deciency is one of the preventable causes of HL.Although it is a
rare, about 1/60,000, metabolic disease in the Western population, the incidence
may be as high as about 1/7000in countries such as Turkey and Brazil [6, 26, 27].
When biotinidase deciency is diagnosed in the neonatal period, it is possible to
prevent HL with biotin supplements [27]. Neonatal biotinidase activity screening is
routine in many countries’ newborn screening programs.
Some of the most common syndromes associated with deafness are summarized
in Table2.2 [6, 22, 23].
Nonsyndromic Hearing Loss
Nonsyndromic HL constitutes the vast majority (80%) of the genetic HLs and can
be caused by mutations in nuclear and mitochondrial genes. Inheritance is mostly
(80%) in an AR manner. Autosomal recessive nonsyndromic HL inherited from
normal-hearing parents is the most common (75–80%) scenario among congenital
genetic HLs [19]. The risk is even higher in consanguineous marriages and assortative matings among the deaf population [28].
Gap junction protein beta-2 (GJB2) gene mutations are the most common cause
of nonsyndromic deafness and account for about 30–50% of all cases [29]. More
than 100 distinct mutations affect the GJB2 gene, but 35delG consists of about 70%
of all mutations [30]. The gap junction protein beta-2 gene encodes a transmembrane protein, connexin 26, expressed widely in stria vascularis and the basement
membrane of the cochlea. Connexin 26 protein is essential in potassium (K+) ion
homeostasis and maintaining the high endocochlear potential necessary for normal
inner ear function [31]. The pathology in connexin 26-related deafness is limited to
cochlear hair cell damage, and higher brain functions are expected to be normal,
unlike in many connexin 26 unrelated etiologies. Histopathologic evaluations
revealed normal neural infrastructure and spiral ganglion cell population despite the
severe degeneration of sensory cells in connexin 26-related deafness [32]. These
make GJB2-related deaf children excellent candidates for cochlear implantation, as
cochlear implants bypass the cochlear hair cells and directly stimulate the spiral
ganglion cells [33].
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Table 2.2 Summary of features, type of inheritance and incidence of some of the most common
syndromic hearing loss
Syndrome
Pendred
syndrome
Usher syndrome SNHL, vestibular symptoms, retinal
Waardenburg
syndrome
Branchio-otorenal syndrome
Alport’s
syndrome
X-linked
deafness
Treacher Collins
syndrome
Jervell and
Lange-Nielsen
syndrome
Biotinidase
deciency
AR autosomal recessive, AD autosomal dominant, EVA enlarged vestibular aqueduct, SNHL sensorineural hearing loss, XL X-linked
a
Adapted and modied from Ref. [6, 22, 23]
a
Characteristic features Inheritance
EVA and SNHL, vestibular symptoms,
and goiter
dystrophy, hematuria, and renal failure
Hearing loss, hypopigmentation in the
eye, skin, or hair, white forelock,
heterochromia iridis, and dystopia
cantorum
Hearing loss, branchial arch
malformations (branchial stula, external
auditory canal, and auricula
malformations, pre-auricular pits), and
renal malformations
SNHL, hematuria, progressive renal
failure, and ocular abnormalities
Characteristic with incomplete partition
type 3 malformation of the cochlea
(bulbous internal auditory canal, absent
modiolus). Progressive hearing loss
Midface hypoplasia, microtia, cleft palate,
and conductive type hearing loss
SNHL, prolonged QT interval, syncopal
attacks, and sudden death
Neurologic and cutaneous abnormalities:
SNHL, seizures, ataxia, hypotonia, visual
problems, and alopecia
AR 4–10%
AR 4–6%
AD/AR 1–4%
AD 2%
XL/AR 1%
XL >1%
AD 1%
AR 0.25–0.5%
AR 1/7000–
Incidence
(among deaf
people)
1/60,000in the
general
population
a
Sensorineural HL is common in mitochondrial diseases. Mitochondrial HL may
occur in isolation or as a component of a syndrome. Pathogenic mitochondrial
deoxyribonucleic acid (mtDNA) is transmitted by maternal inheritance. The onset
of mtDNA-related SNHL tends to be in infancy or early life, with a gradual progression. Hearing loss is exclusively symmetrical, sensorineural, and progressive and
primarily affects the higher frequencies in mitochondrial disease. The penetration of
the mutation may vary, and the onset and severity of the HL may differ even in family members carrying the same genetic variations. Some pathogenetic variants in
mtDNA, such as A1555G, are associated with a predisposition to aminoglycoside
ototoxicity [34, 35].
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2.2.1.2 Intrauterine Infections
Although intrauterine infections of viral, protozoal, and bacterial pathogens can
cause congenital HL, viral infections are incomparably more common and solely
responsible for about 40% of nongenetic congenital HL. Hearing loss related to
intrauterine infections is sensorineural, and severity and onset characteristics may
vary depending on the infectious agent [36]. Common infectious causes of congenital HL are cytomegalovirus (CMV), rubella, toxoplasmosis, syphilis, herpes simplex virus type 1 and 2 (HSV-1, HSV-2), Zika virus, human immunodeciency virus
(HIV), and lymphocytic choriomeningitis virus (LCMV).
Congenital CMV infection (cCMVI) is the most common congenital infection
and the most common cause of congenital infection-related HL.The prevalence of
cCMVI is 0.4–2.3% in newborns and 6–7% among individuals with congenital HL
[37]. About 10–15% of infants with cCMVI are diagnosed with unilateral or bilateral SNHL; of these, 3–5% have bilateral moderate to profound HL [38, 39].
Congenital CMVI may cause delayed-onset HL; up to 43% of newborns with
cCMVI pass the hearing screening but develop SNHL in the following period [37].
Close follow-up and audiologic monitoring are required in all infants with cCMVI
to avoid delayed diagnosis and intervention of HL.
Rubella is a common cause of congenital infections. Although rubella was
eradicated in many high-income countries with large-scale immunization, it still
is an important cause of intrauterine infections in low- and middle-income countries. Congenital rubella syndrome (CRS) is a devastating intrauterine infection
characterized by HL, growth retardation, and neurologic, visual, and cardiac
defects. Rubella infection within the rst trimester results in CRS in 90% of newborns [40]. The prevalence of HL in congenital rubella infection is as high as 19%
[36]. As nonimmune pregnant women constitute a signicant risk for developing
CRS, maternal vaccination is critical to avoid this devastating infection’s
consequences.
Congenital toxoplasmosis is another tragic intrauterine infection associated with
HL. Fetal transmission generally occurs in primary Toxoplasma gondii infection
during pregnancy [41]. As most infections are asymptomatic, the screening of
Toxoplasma-specic antibodies in all pregnant women is recommended [41, 42].
Congenital syphilis was a common cause of congenital HL.It still is a cause of
congenital HL in low- and middle-income countries. However, after the introduction of penicillin and prevention and treatment programs, congenital syphilis prevalence decreased gradually for decades and is a very exceptional entity today in
high-income countries [43]. Hearing loss in congenital syphilis is progressive and
delayed-onset in most affected children. Hearing tests are usually normal in the
neonatal period, and screening tests may be ineffective [44].
Congenital Zika syndrome (CZS) is associated with numerous congenital malformations, including microcephaly. Adverse outcomes of CZS were reported as
much as 46% [45]. Current literature supports a possible association between CZS
and HL, and prompt audiologic evaluation of infected newborns is recommended [46].
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2.2.2 Perinatal Period
2.2.2.1 Perinatal Asphyxia
Perinatal asphyxia can trigger neuronal injury that may result in hypoxic–ischemic
encephalopathy (HIE). The prevalence of perinatal asphyxia is about 2%, and
although most recover entirely, 0.16% of newborns develop HIE [47]. Hypoxic–
ischemic injuries frequently cause sensory impairments, including HL, due to the
permanent disruption of hair cells in the organ of the Corti. Hearing loss following
HIE is reported as high as 17.1% in patients with accompanying neurologic impairments [48].
2.2.2.2 Hyperbilirubinemia
The prevalence of neonatal jaundice in term and late preterm newborns is 84% [49].
It is mostly transient, and long-term complications are rare. But neurologic decits
like HL may occur in some infants, particularly those with bilirubin levels over
20mg/dL.Hearing loss is commonly caused by damage to the auditory nerve or
brainstem and presents as auditory neuropathy spectrum disorder (ANSD). Hearing
loss is more common in premature infants as they are more susceptible to bilirubin
toxicity [50].
2.2.2.3 Low Birth Weight
As access to neonatal intensive care units (NICUs) has become widespread, survival
rates of very low birth weight (VLBW, <1500g) infants have substantially increased.
The incidence of HL is signicantly higher in VLBW infants. There may be no
direct relationship between birth weight and HL.Still, VLBW is associated with
various risk factors, such as hyperbilirubinemia, the requirement for ototoxic medications, and hypoxia that may synergistically impair hearing [16].
2.2.2.4 Perinatal Infections
The most common cause of acquired HL in infancy and early childhood is bacterial
meningitis which accounts for about 6% of all SNHLs [51]. Most cases are under
2years of age and have bilateral HL [52]. Bacterial meningitis results in SNHL in up
to 30% of pediatric patients [53]. The pathogenesis of SNHL in bacterial meningitis
depends on suppurative labyrinthitis due to bacterial infection spread from the subarachnoid space to the cochlea through the cochlear aqueduct. The inammatory process in the inner ear frequently leads to brosis and subsequent ossication of the
perilymphatic spaces, causing the destruction of the sensory hairy cells. The brosis
and ossication may occur as early as weeks after the onset of meningitis [54].
Occlusion of the cochlear duct by brous tissue and subsequent ossication, and labyrinthitis ossicans, consists of an obstacle for cochlear implantation in case of severe
SNHL. Therefore, severe hearing impairment after meningitis is an emergency for
cochlear implantation. Patients with residual hearing compensable with conventional
hearing aids should be followed up closely with audiologic and radiologic monitoring.
Care must be taken to avoid missing progressive HL and cochlear ossication, which
will make the salvage therapy, and cochlear implantation much more complicated [55].
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