Observations on Pediatric Practice

Educational Objectives

The goal of this program is to improve the management of pediatric hearing disorders and respiratory abnormalities. After hearing and assimilating this program, the participant will be better able to:

1.   Recognize and test for auditory dyssynchrony and hearing impairment in children.

2.   Identify the common abnormalities associated with hearing loss in children and diagnose hereditary hearing loss.

3.   Describe the syndromes that commonly cause hearing loss in children.

4.   Effectively implement genetic testing and clinical evaluation to diagnose syndromic and nonsyndromic hearing loss.

5.   Choose appropriate treatments when presented with difficult cases, such as eustachian tube dysfunction sec­ondary to Down syndrome, and children with respiratory distress and stridor.

Faculty Disclosure

In adherence to ACCME Standards for Commercial Support, Audio-Digest requires all faculty and members of the planning com­mittee to disclose relevant financial relationships within the past 12 months that might create any personal conflicts of interest. Any identified conflicts were resolved to ensure that this educational activity promotes quality in health care and not a proprietary business or commercial interest. For this program, the faculty and the planning committee reported nothing to disclose. Drs. Holinger, Miller, and Schroeder presented information related to off-label use of a therapy, product, or device.

Acknowledgements

Dr. Grundfast’s lecture was recorded at Masters of Otolaryngology Symposium: Temporal Bone Dissection and Otology Up­date, held February 20-21, 2009, in Augusta, GA, and presented by the Medical College of Georgia, Division of Continuing Education and School of Medicine. The panel discussion was recorded at Young Guns and Wisemen Panel Discussion of Common Controversial Pediatric Cases, held November 3, 2008, in Chicago, IL, and presented by the Chicago Laryngolog­ical and Otological Society. The Audio-Digest Foundation thanks the speakers and the sponsors for their cooperation in the production of this program.

Top 10 Things You Need to Know About Pediatric Hearing Disorders

Kenneth M. Grundfast, MD, Professor and Chair, Department of Otolaryngology – Head and Neck Surgery, Boston University School of Medicine, Boston, MA

Parents know when children have impaired hearing: parents generally know when their child has hearing impair­ment (HI) before audiologic tests confirm hearing loss (HL)

Early detection of childhood HI mandatory: in United States before 1970, HI not detected in children until ³3 yr of age; at time of Consensus Conference Joint Committee on Infant Hearing in 1993, high-risk register used to de­termine which newborns at risk for HI and in need of testing; by 2005, 95% of newborns screened for HL, re­gardless of risk factors; now, Congress has mandated development of Early Hearing Detection and Intervention (EHDI) systems as described at Department of Health and Human Services (HHS) website; additional informa­tion available on website of National Center for Hearing Assessment and Management

Recommendations from Joint Committee on Infant Hearing (2007): access to hearing screening for all infants using physiologic measure at £1 mo of age; hospitals may use either auditory brainstem response (ABR) or otoacoustic emissions (OAE), but most use combined tests; rescreen all infants who fail initial testing; all infants with con­firmed permanent HL should receive early intervention services as soon as possible (£6 mo of age); provide in­formation about interventions including manual communication (sign language), hearing aids, and cochlear implants; continued monitoring of children in home and assessment of development of communication; provide interdisciplinary intervention programs

Auditory dyssynchrony (auditory neuropathy): recognition and diagnosis increasing because of universal screen­ing; characterized by presence of OAE, absent or abnormal ABR, normal function of outer hair cells, but abnor­mal neural function at level of vestibulocochlear nerve; seen with hyperbilirubinemia and associated with various neurologic abnormalities; many cases resolve in 3 to 6 mo; amplification not appropriate, but cochlear implants helpful for severe persistent cases; associated abnormalities  —  gait ataxia, hereditary motor sensory neuropathy (Charcot-Marie–Tooth syndrome), and Friedreich’s ataxia; additional information available on website of Na­tional Institute on Deafness and Other Communication Disorders (NIDCD)

Speaker’s experience: »50% of apparently normal children with absent ABR but present OAE improve within 6 mo

Hearing tests in children: accuracy relative and evolving; hearing complex and includes response to auditory stimuli (measured electrophysiologically) and comprehension of auditory input; behavioral tests show what child really hearing; accuracy of testing improves over years and depends on skill of audiologist in working with children

Newly discovered vs newly occurring sensorineural hearing loss (SNHL): unlike newly discovered HL, newly oc­curring HL may indicate progression and potential for additional loss in future; differentiate by obtaining records of newborn screening test, performing computed tomography (CT) to look for congenital abnormality, or performing genetic tests; mild congenital unilateral or bilateral HI or HL often missed until child about to enter kindergarten; new requirements for newborn screening expected to phase out this problem

Delayed development of speech: speaker has observed that children referred for hearing evaluation because of de­layed development of speech usually have normal hearing; evidence of development of speech usually begins at »14 mo of age; examine ears and oral cavity, observe child’s behavior, and obtain hearing test; speaker has noted that boy’s age at onset of speech correlates with age at which father began speaking; if child does not speak by 2 to 2.5 yr of age, order audiology testing but consider possibility of developmental delay including pervasive develop­mental delay, autism, attention-deficit disorder, or attention-deficit/hyperactivity disorder; early indication of these disorders sometimes apparent from child’s behavior in office and during examination

Sudden SNHL in an adolescent: in speaker’s experience, usually functional; bilateral symmetric SNHL without ev­idence of neurologic disorder rare; unilateral sudden SNHL occurs, but important to rule out functional (nonor­ganic) HL

Association of childhood HL with other abnormalities: most congenital SNHL nonsyndromic; »80% of HL results from recessive, »18% from dominant, 2% from X-linked, and small fraction from mitochondrial mutations; con­genital HL present at birth; hereditary HL caused by abnormal gene or mutation; examples  —  rubella, cytomega­lovirus, and fetal alcohol syndrome cause congenital, but not hereditary, HL; otosclerosis (autosomal dominant but 50% penetrant), delayed onset nonsyndromic auditory dominant progressive SNHL (affects hearing between 10 and 20 yr of age), and Usher syndrome type 2 cause hereditary, but not congenital, HL

Diagnosing hereditary HL: determine type of HL, age at onset, stability, family history, and physical findings; chil­dren with some syndromes may appear normal (eg, children with Alport syndrome have abnormal kidney func­tion, and those with Jervell and Lange-Nielsen syndrome have abnormal cardiac rhythm); shape of audiogram (eg, U-shape or “cookie bite” audiogram) suggests hereditary HL

Family history: presence of affected sibling, parent, or grandparent in infant with HL, or HL in adolescent who has affected older sibling, parent, or grandparent, suggests autosomal dominant disorder; however, infant with heredi­tary HL due to autosomal recessive mutation may have no family history of HL

Syndromic vs nonsyndromic: »30% of patients have syndromic HL associated with noticeable abnormalities (often ocular or pigmentary); »60% of patients have nonsyndromic HL and appear normal

Causes of HL

Usher syndrome: autosomal recessive; characterized by retinitis pigmentosa, and SNHL; type 1  —  congenital with ataxic gait due to loss of vestibular function; type 2  —  probably progressive with normal vestibular function and gait

Pendred syndrome: autosomal recessive; nontoxic goiter (usually euthyroid); genetic test available; associated with both Mondini and enlarged vestibular aqueduct deformities

Jervell and Lange-Nielsen syndromes: autosomal recessive; associated with prolonged QT interval, syncope, and risk for sudden death

Treacher Collins syndrome: autosomal dominant; expression varies widely; characteristics  ¾  include constricted midface, anti-mongoloid slant of eyes, and cup-shaped ears; SNHL, conductive, or mixed HL; stenosis or atresia of external auditory canal; congenital fixation of stapes; poorly pneumatized mastoid; patients not candidates for sur­gical correction; not always easily recognized, as children may appear normal

Waardenburg’s syndrome: pigmentary disorder; autosomal dominant with 95% penetrance, but gene expression highly variable; patients with type 1 have lateral displacement of medial canthi (dystopia canthorum); often have confluent eyebrows and very blue eyes; distinct from hypertelorism (orbits displaced laterally); patients may have poliosis and may or may not have HI

X-linked mixed HL with stapes gusher: men affected and women carry mutation; diagnosed by CT showing bul­bous lateral aspect of internal auditory canal with potential connections between cerebrospinal fluid (CSF) space and vestibule

Branchio-oto-renal (BOR) syndrome: »10% of population has preauricular pits; presence of branchial cleft cysts and HI suggests BOR

Fetal alcohol syndrome: characteristics include longer distance between columella and upper lip, absent philtrum, and low hairline

Cytomegalovirus: patients with severe form have chorioretinitis and mental retardation

Radiographic abnormalities: enlarged vestibular aqueduct most common radiographic abnormality associated with HL in children; linked to abnormality in gene encoding pendrin protein

Genetics: many mutations causing HL identified; genetic tests available for syndromic forms of HL, including Treacher Collins, BOR, and Waardenburg’s; those for nonsyndromic HL include mitochondrial abnormalities; ex­tensive information available on websites of NIDCD and Hereditary Hearing Loss

Evaluation

Genetic testing: available from commercial laboratories; connexin 26 most commonly mutated gene in nonsyn­dromic HL; mitochondrial mutations more likely in teenagers and adults

Recommendations: speaker recommends obtaining history including family history, performing physical examina­tion and appropriate genetic testing, and CT in patients 12 to 18 mo of age; consider consultation with clinical ge­neticist; ask pediatrician to order electrocardiography and tests for hematuria and proteinuria

Controversial Cases: A Panel Discussion

Lauren D. Holinger, MD, Professor of Pediatric Otolaryngology, Professor of Otolaryngology–Head and Neck Surgery, and Head of Otolaryngology, Feinberg School of Medicine, Northwestern University (moderator)
Andrew J. Hotaling, MD, Professor of Pediatric Otolaryngology–Head and Neck Surgery, Loyola University Medical Center; Robert P. Miller, MD, Assistant Professor of Otolaryngology–Head and Neck Surgery, Fein­berg School of Medicine, Northwestern University; James W. Schroeder Jr, MD, Clinical Instructor of Otolar­yngology–Head and Neck Surgery, Northwestern University, Feinberg School of Medicine; Dana L. Suskind, MD, Associate Professor of Surgery and Pediatrics, and Director, Pediatric Cochlear Implantation Program, University of Chicago Medical Center (all Chicago, IL)
Cecille G. Sulman, MD, Assistant Professor, Medical College of Wisconsin, Children’s Hospital of Wiscon­sin, Milwaukee

Case Example 1

Background: 2-mo-old infant with Down syndrome and no cardiac problems passed newborn hearing test; examina­tion showed very narrow external auditory canals; high-frequency tympanometry (HFT) produced normal results on left (not possible to perform on right)

Follow-up: important to keep ears clear of cerumen (significant problem in Down syndrome) and examine again in 6 to 8 wk; at 6 wk of age, eardrums did not appear to move well and HFT gave no response in either ear; children with Down syndrome have higher incidence of eustachian tube dysfunction; speaker recommends following patient for another 2 mo before placing tympanostomy tubes; moderator preferred placing tubes early (at »1 mo); tubes placed by 6 mo of age

Placement of tubes: very small titanium tubes available, but these tend to come out quickly; Shea parasol tubes have small diameter and remain in place 9 to 12 mo; panelist also recommended Teflon collar-button tube using serially increasing diameters of specula to dilate canal; follow-up every 3 to 4 mo for cleaning because narrow canal causes functional HL due to impaction of cerumen; use tympanometry liberally to determine status; lack of treatment for hearing problems in children with Down syndrome can impede development; consider canaloplasty in children with canals too small for placement of tubes

Case Example 2

Background: 2-mo-old infant seen for possible respiratory distress and stridor (present since birth); primarily inspi­ratory but sometimes biphasic

Stridor: inspiratory stridor suggests supraglottic or extrathoracic problem; biphasic stridor suggests problem at glot­tis; expiratory stridor suggests intrathoracic problem (eg, bronchomalacia or tracheomalacia); difficulty breathing during exertion or while feeding suggests laryngeal, tracheal, or bronchial problem; worsening during sleep indi­cates pharyngeal location (above larynx); laryngomalacia possibly worse in supine vs prone position; many chil­dren with inspiratory stridor have evidence of aspiration, eg, coughing while feeding

Mnemonic to guide treatment (SPECS): severity of problem; progressive; difficulty eating and swallowing (eg, as­piration or failure to thrive); cyanosis or apneic events; sleeps quietly without obstruction (laryngomalacia some­times worse during sleep)

Flexible fiberoptic laryngoscopy: showed normal movement of vocal cords and presence of subglottic mass; speaker discussed laryngoscopy, bronchoscopy, and possibility of surgery with parents; laryngoscopy showed se­vere obstruction of airway, despite minor symptoms; diagnosis subglottic hemangioma

Treatment: options include immediate laser treatment, or medical treatment with steroid therapy or propranolol; la­ser can create subglottic stenosis, so panel recommended limiting removal to 25% to 33% (or <50%) of circumfer­ence at one time; alternative options include tracheostomy or laryngotomy and open excision, but endoscopic treatment preferred; endoscopic CO₂ laser treatment performed treatment with injection of steroids into base and intubation for 48 hr, followed by extubation and reevaluation in operating room; if open laryngotomy and excision performed, possible to place small piece of cartilage to augment subglottic airway and avoid tracheotomy; one arti­cle reported response of several cases of facial hemangioma to propranolol at 2 mg/kg per day administered for heart problems; magnetic resonance imaging (MRI) can reveal extent of lesion, but important to initiate treatment immediately and not delay to obtain MRI

Suggested Reading

Aguilar Caso SI, Ortiz Nieva G: Waardenburg syndrome in four Mexican patients. J Pediatr Opthalmol Strabismus 46:120, 2009; Borck G et al: Genetic causes of goiter and deafness: Pendred syndrome in a girl and co-occurrence of Pen­dred syndrome and resistance to thyroid hormone in her sister. J Clin Endocrinol Metab 94:2106, 2009; Chau J et al: A systematic review of pediatric sensorineural hearing loss in congenital syphilis. Int J Pediatr Otorhinolaryngol 73:787, 2009; Cristobal R, Oghalai JS: Hearing loss in children with very low birth weight: current review of epidemiology and pathophysiology. Arch Dis Child Fetal Neonatal Ed 93:F462, 2008; Dowley AC et al: Auditory neuro-pathy: unexpectedly common in a screened newborn population. Dev Med Child Neurol Mar 20, 2009 [Epub ahead of print]; Emery SB et al: Otosclerosis or Congenital Stapes Ankylosis? The Diagnostic Role of Genetic Analysis. Otol Neurotol May 22, 2009 [Epub ahead of print]; Frey U, von Mutius E: The challenge of managing wheezing in infants. N Engl J Med 14:360, 2009; Joy T et al: Alstrom syndrome (OMIM203800): a case report and literature review. Orphanet J Rare Dis 2:49, 2007; Katbamna B et al: Hearing impairment in children. Pediatr Clin North Am 55:1175, 2008; Mehra S et al: The epidemiology of hear­ing impairment in the United States: newborns, children, and adolescents. Otolaryngol Head Neck Surg 140:461, 2009; Parkin M, Walker P: Hearing loss in Turner syndrome. Int J Pediatr Otorhinolaryngol 73:243, 2009; Pober Br et al: A review of Donnai-Barrow and facio-oculo-acoustico-renal (DB/FOAR) syndrome: clinical features and differential diagno­sis. Birth Defects Res A Clin Mol Teratol 85:76, 2009; Roberts JE et al: Language and communication development in Down syndrome. Ment Retard Dev Disabil Res Rev 13:26, 2007; Skarzynski H, Podskarbi-Fayette R: Treatment of oto­rhinolaryngological manifestations of three rare genetic syndromes: Branchio-Oculo-Facial (BOF), Ectrodactyly Ectoder­mal dysplasia Clefting, and focal dermal hypoplasia (Goltz syndrome). Int J Pediatr Otorhinolaryngol 73:143, 2009; Trainor PA et al: Treacher Collins syndrome: etiology, pathogenesis, and prevention. Eur J Hum Genet 17:275, 2009; Withrow KA et al: Impact of genetic advances and testing for hearing loss: results from a national consumer survey. Am J Med Genet A 149A:1159, 2009; Yanmei F et al: Cochlear implantation in patients with Jervell and Lange-Nielsen syn­drome and a review of the literature. Int J Pediatr Otorhinolaryngol 72:1723, 2008.