Otitis Media

Mary Bennett, Amanda Buisman & Roline Campbell

Pertinent AnatomyOssicles

(malleus, incus, stapes)

ORTympanic Membrane

External Ear Canal

ORAuricl

e

Pertinent Anatomy

(Cone of light)

Physiology of the Ear

External Ear

Consists of the pinna (auricle) and the auditory ear

canal

• The pinna functions to both protect the tympanic

membrane, and to collect sound waves.

• The auditory ear canal distributes sounds in the

form of pressure waves to the tympanic

membrane.

Physiology of the EarMiddle Ear

Consists of the tympanic membrane, auditory ossicles

(malleus, incus, stapes) and the eustachian tube.

• The tympanic membrane receives sound waves (in the

form of pressure waves) from the auditory ear canal and

converts the waves into mechanical vibrations by way of

the auditory ossicles. The mechanical vibrations are then

transmitted to the inner ear.

• The eustachian tube links the pharynx to the middle ear

and while it is normally closed, it can let a small amount

of air though to equalize the pressure between the

middle ear and the atmosphere. It also drains mucous

from the middle ear.

Physiology of the EarInner Ear

Consists of the semicircular canals, vestibule, acoustic nerve,

and the cochlea.

• Mechanical vibrations are received from the TM and are

transformed into fluid vibrations, which are then converted

into nerve impulses by nerve endings located in the cochlea.

These impulses are conducted via the auditory nerve to

higher levels and interpreted as sound by the brain.

• The semicircular canals and vestibule function to maintain

balance and equilibrium.

Pathophysiology of Otitis Media (OM)

OM is defined as inflammation in the middle ear

without reference to etiology. OM is one of the most

common reasons for a child to visit the pediatrician.

OM can be classified into four categories;

• Acute Otitis Media (AOM)

• Otitis Media with Effusion (OME)

• Recurrent AOM

• Chronic OME

Pathophysiology of Acute Otitis Media (AOM)

The most important factor in the pathogenesis of

AOM is abnormal function of the eustachian tube.

• Reflux, aspiration, or insufflation of

nasopharyngeal bacteria into the middle ear via

the dysfunctional eustachian tube may lead to

infection.

• Eustachian tube dysfunction occurs due to either

abnormal patency, or obstruction (either

functional or mechanical).

Pathophysiology of Acute Otitis Media (AOM)

Common causative microorganisms for AOM

are:

• Streptococcus pnumoniae (30-50% of

cases)

• Haemophilus influenzae (20-30% of cases)

• Moraxella catarrhalis (7-25% of cases)

Acute Otitis Media (AOM)With and Without Perforation

When AOM is present and the TM is intact,

it is referred to as “AOM without

perforation”.

When AOM is present and the TM is NOT

intact, it is referred to as “AOM with

perforation”.

AOM with PerforationAOM with perforation has two categories;

• AOM complicated by perforation of the tympanic

membrane presenting as otorrhea. (Left)

• AOM in a patient with tympanostomy tubes. (Right)

OM with Effusion (OME)

OME occurs when thick fluid accumulates behind the TM. OME typically occurs

immediately following treatment of AOM due to the resolution of acute

inflammation, allowing visualization of the middle ear fluid behind the TM.

Epidemiology

The overall prevalence of AOM is 15-20%, with

the highest peak at 6-36 months of age.

An additional smaller peak occurs at 4-6 years of

age.

Between 60-80% of infants have had at least

one episode of AOM by one year of age.

AOM is uncommon in older children and

adolescents.

Epidemiology

AOM is more common in boys, and the

prevalence is greatest in Alaskan natives

and Native Americans (Caucasian race is

also considered a risk factor however).

AOM is most common in the winter

months and in early spring, coinciding

with peaks in the incidence of URI’s.

EpidemiologyRisk factors for developing OM;

• Male gender

• Absence of breastfeeding

• White race

• Passive exposure to tobacco smoke

• Daycare attendance

• Low socioeconomic status

• Presence of siblings in the household

• Altered host defenses/underlying conditions

Patient Evaluation-History

Clinical presentation- children with AOM often have a

history of rapid onset of fever and ear pain (usually

within 48 hours). The patient may also have hearing

loss, otorrhea, and irritability. Nonverbal children

present with “ear pulling” and generalized fussiness.

Associated symptoms include URI, cough, diarrhea,

and nonspecific complaints such as decreased

appetite, waking at night, or irritability in infants.

Patient Evaluation- HistoryIt is important in the history to differentiate

nonspecific symptoms of OM from those

indicating a more serious condition such as

meningitis.

For infants or children with a history of

persistent or recurrent OM, it is important to

find out when they had their last documented

infection and what treatment they received.

Patient Evaluation- HistoryHelpful questions to ask when

obtaining the patient’s history;

• Does the infant have fever, ear pain, hearing

loss, or otorrhea?

• Is the infant/child inconsolable or lethargic?

• Has the infant/child had a previous ear

infection? If so, when?

• Did the child complete the course of

prescribed antibiotics?

Helpful Questions• How many ear infections has the child had in

the past year?

• Is the child taking any medication to prevent

recurrent OM?

• Does the child attend daycare?

• Is the child exposed to passive smoke?

• Is the infant breast-fed?

• Does the child appear to hear?

• Is the child’s speech development normal?

Physical Exam Findings

To diagnose OM, the TM must be

visualized. The position, color,

degree of translucency, and mobility

of the TM must be evaluated.

Classically, in AOM the TM is full or

bulging, opaque, and has limited or

no mobility, or is retracted. The light

reflex is usually absent or distorted.

Physical Exam FindingsAssociated physical exam findings may

include;

• posterior auricular and/or cervical

adenopathy

• pain on movement of the pinna

• anterior ear displacement

*The presence of these symptoms may also suggest a more serious condition

such as mastoiditis therefore thorough history taking and visualization of the TM

is essential.

Normal (no AOM present) Exam Findings

Position- process of the malleus should be

visible but not prominent through the

membrane.

Color- pearly gray.

Translucency- middle ear or bony landmarks

should be visible through the TM.

Mobility- normal ear will move with

pneumatic otoscopy.

Physical Exam Findings

Here is a normal TM

Physical Exam Findings

Here is a picture of a typical TM with AOM. The TM is noted to appear erythematous or injected in color, the light reflex is absent, landmarks are poorly visualized, and there is a poor degree oftranslucency.

Physical Exam Findings

Here is an example of AOM with a bulging TM. Note the color, position, transparency, lack of visible landmarks,and distorted light reflex

Physical Exam Findings

Here is a retracted TM

Diagnosis of AOM• Accuracy in diagnosis of utmost

importance• Ensures appropriate treatment for

AOM• Avoids unnecessary use of

antibiotics in OME• Prevents overuse of antibiotics –

considered a major factor in increased drug-resistance

AOM in Infants & Children

• Challenges in establishing a diagnosis:

– Uncooperative

– TM obscured by cerumen

– Symptoms of AOM may overlap with other conditions (URI)

– Symptoms may be subtle or even absent

• Successful diagnosis facilitated by:

– Systematic assessment

– Stringent diagnostic criteria

– Training and experience

AAP & AAFP Diagnostic Criteria Three diagnostic criteria

1. Recent, abrupt onset of ME inflammation & effusion (ear pain, irritability, otorrhea, and/or fever)

2. MEE confirmed by:– bulging TM,– limited or absent mobility (pneumatic otoscopy),– air-fluid level behind TM, or– Otorrhea (with TM not intact)

3. Evidence of ME inflammation - confirmed by:– distinct erythema of TM, or – distinct otalgia interfering with normal sleep or

activity

Diagnostic Techniques• Pneumatic otoscopy

– Assess inflammation

– Assess effusion

– Assess perforation & character of otorrhea

• Tympanometry and/or acoustic reflectometry

– Assess/confirm effusion

• Tympanocentesis (by otolaryngologist)

– Identify infectious organism

– Use in special populations

TympanometryAcoustic

Reflectometry• Analyzes sound reflected off the TM to detect MEE

• No pressure seal required

• Small quantity of cerumen does not affect this test

• Increased use in primary care

• Accurate & objective assessment of effusion

• Requires an air-tight seal & pressurization of the ear canal

• Painful & uncomfortable for children

• Limited use & costly

Pneumatic Otoscopy

• Allows direct visualization of TM & ear structures

to confirm presence of inflammation, effusion and

assess for perforation.

• Important to:

– Remove cerumen obscuring TM

– Ensure adequate lighting

– Appropriately restrain the child to allow examination

& prevent injury

– For pneumatic otoscopy – adequate airtight seal by

choosing correct size and shape speculum.

Assessment of the TM

• Locate border between external ear canal & TM

• Assess:

– Surface

– Opacity

– Color

– Mobility

– Other findings

The Surface of the TM

• Are the landmarks

visible?

• Are the landmarks

obscured or unusually

prominent?

• Where is the cone of

light?

• Is the TM intact?

Retracted & Bulging TMAbnormally retracted TM Bulging TM

Opacity of the TM

Normal Tympanic Membrane- Usually translucent

Scarred Tympanic Membrane

- note loss of translucency at area of scar

Color of the TMExpected Findings

• Normal TM = Pearly grey

• Crying infant = Pink TM

• Classic AOM = red or

infused TM

• Atypical AOM = white or

yellow TM (from purulent

middle ear fluid)

AOM with infused

erythema

Mobility of the TM• Successful pneumatic otoscopy requires airtight seal of external ear canal

• With normal mobility the TM will– move inward when positive pressure is

applied– move outward when negative pressure is

applied• A retracted TM will show – decreased or absent inward deflection– but normal outward deflection with negative

pressure• Crying children have increased middle ear

pressures during exhalation which fleetingly normalize during inspiration

• Severely diminished or absent mobility is indicative of effusion

Normal TM Movement

Decreased TM Movement

Other Findings

Air-fluid level behind the TM

- Indicative of Middle Ear Effusion (MEE)

Cholesteatoma – grey or white mass behind the TM

Blebs / blisters on the surface of the TM – Bullous Myringitis

Cholesteatoma →

↖ Bleb / blister

Clinical Diagnosis of AOM

Requires:

Acute onset of symptoms AND

Middle Ear Effusion AND

Middle Ear Inflammation

OR

Acute purulent otorrhea

via perforated TM or tympanostomy tube

AND otitis externa has been excluded

Differential DiagnosesViral

MyringitisOME AOM

Otalgia Present

Usually absent - some reports "fullness“

Acute pain

InflammationPresent Absent Present

Bulging TM No bulgingNormal position or retracted

Bulging

TM Mobility Normal Decreased Decreased

Diff. Dx

S & S

AOM or OME?

Two year old Ron’s mom reports him rubbing and

slapping at his left ear since early this morning. He

refused breakfast and has been irritable all day.

Pneumatic otoscopy reveals a bulging, yellow

tympanic membrane with marked decrease in

mobility.

Is this AOM or OME?

Summary: MEE• MEE (Middle Ear Effusion) = fluid in

middle ear

• Occurs in both AOM and OME

• OME often precedes development of

AOM

• OME mostly also follows resolution of

AOM

OM with ruptured TMAOM with TM intact

• Acute onset otalgia

• Inflamed TM

• Middle Ear Effusion present (Bulging and decreased mobility)

AOM with ruptured TM

(or with Tympanostomy tube)

• History of acute onset otalgia which improved when ear started draining (relief of pressure when TM ruptured)

• Inflamed TM

• TM ruptured & draining purulent fluid into external ear canal

Treatment of AOM

• Clinical course of 24 – 72 hours with

appropriate antimicrobial Rx

• Slightly slower resolve of acute

symptoms when not treated

• MEE may persist for weeks or months

Clinical Practice Guideline

• AAP and AAFP Clinical Practice Guidelines

(2004) state that the following aspects of

management should be considered:

1. Symptomatic therapy

2. Observation (“Watchful waiting”)

3. Appropriate antimicrobial therapy

1. Symptomatic Therapy - Pain• Acetaminophen

– 10 -15mg/kg PO/PR every 4 – 6 hours as needed

– not to exceed 90mg/kg/day

• Ibuprofen– 5 - 10mg/kg PO/PR every 6 – 8 hours as

needed– not to exceed 40mg/kg/day

• Topical agents– Antipyrine-benzocaine otic drops– 4 – 5 drops into affected ear(s) every 2 hours

as needed– not to be given in case of TM perforation– Aqueous lidocaine ear drops (30 minute

efficacy – needs further evaluation – not currently a recommendation)

Treatment of pain (cont.)

• Complementary treatments

– Herbal extracts:

• Otikon Otic solution

• Compared well to topical anesthetic

• Home remedies

– Distraction

– External application of heat or cold

– Instillation of oil into external auditory canal

– Clinical evidence still lacking

Symptomatic Therapy - Congestion

• Decongestants and antihistamines– Still commonly used in some populations

– No proof of efficacy in treatment of AOM

– Demonstrated:• Increased medication side-effects

• Did not improve healing or reduce complications/surgery

• Prolonged duration of MEE

• AAP recommends OTC cough and cold medications NOT used in infants & children < 2 years (danger of life-threatening side effects!)

2. “Watchful waiting”• Objective is to reduce the unnecessary use of

antibiotics

• Limit development of drug-resistance

• Option only for selected children

• Certain criteria must be met to ensure safety

• “Watchful waiting” is NOT appropriate for any infant < 6 months – Infants < 6 months should be treated with

antibiotics REGARDLESS of the degree of diagnostic certainty.

Considerations for “Watchful Waiting”

• Age of infant/child

• Certainty of diagnosis

• Severity of illness

• Can follow-up be ensured?

• Ability to acquire prescription medications if

needed

• Parents must understand risks and benefits of

“watchful waiting” vs immediate treatment

3. Antimicrobial treatment

• Selection of drugs should be based on: Clinical & microbiologic efficacy Acceptability of the oral preparation

(taste & texture) Absence of side effects and toxicity Convenience of dosing schedule Cost

First-line antimicrobial therapy

Amoxicillin

• Controversy but still recommended as drug of

choice (safe, effective, affordable, narrow spectrum)

• Doubled dose increase concentration in ME

• Then active against most intermediate strains of S.

pneumoniae (including many resistant strains)

• 80 – 90 mg/kg per day (divided in 2 doses)

• Heavier children – max of 3g/day

When is Amoxicillin contra-indicated?

• High risk for AOM caused by an amoxicillin-

resistant otopathogen

– Treated with antibiotics in previous 30 days

(especially beta-lactam antibiotics)

– Concurrent purulent conjunctivitis (non-typable H.

influenzae)

– Receiving amoxicillin chemoprophylaxis for recurrent

AOM or UTI

– Allergy

Alternative 1st Choice treatmentAmoxicillin-clavulanate

• Active against beta-lactamase-producing non-typeable H. influenzae

• Also active against S. pneumoniae• Dosing:

< 3 months: 30mg/kg/day PO divided in 2 daily doses

≥ 3 months & < 40 kg: 90mg/kg/day PO divided in 2 daily doses x 10 days

Children weighing > 40 kg – 250-500mg every 8 hours

Secondary treatment options

• Choice of alternatives depend on type of previous hypersensitivity reaction

HISTORY OF NON-TYPE 1 REACTIONS

Cefdinir • 14 mg/kg/day in 1 or 2 doses (limit total 600mg/day)

Cefpodoxime • 10 mg/kg /day once daily (limit 800 mg/day)

Cefuroxime (cefuroxime axetil suspension)• 30 mg/kg/day in 2 divided doses (limit total 1 g/day)

Cefuroxime tablets• 250 mg every 12 hours

Treating AOM due to Penicillin-resistant S. pneumoniae

• Oral Cephalosporins are not effective against penicillin-

resistant S. pneumonia

• Consider :

Ceftriaxone

• 50mg/kg in single IM dose

• If clinical signs do not improve after 48 hours, a second dose

may be given. In some cases even a third dose may be

necessary.

• Be mindful of the physical discomfort and psychological

distress caused in a young child when following this approach.

Secondary treatment options

HISTORY OF TYPE 1 REACTIONS

Erythromycin plus sulfisoxazole

• 50-150 mg/kg/day in 4 divided doses

• Limit total erythromycin to 2g/day

• Often rejected due to taste and high frequency of dosing

Azithromycin

• Single dose Rx: Give 30mg/kg in one single dose x1 day

• 3-day Rx: Give 20mg/kg/day – one dose daily x3 days

• 5-day Rx: Give 10mg/kg on day 1 & 5mg/kg/day on days

2 – 5

Secondary options cont. HISTORY OF TYPE 1 REACTIONS

Clarithromycin

• 15mg/kg/day divided in 2 doses (limit to

1g/day) OR

• 30-40mg/kg/day divided in 4 doses (limit to

1g/day)

Clindamycin

• 30-40 mg/kg/day divided in 3 – 4 doses

Treatment of AOM in children with Tympanostomy Tubes

• For some children, topical antibiotic therapy may be an alternative to oral therapy.

• Requirements:– Mild to moderate illness– No immune compromise– Must be older than 2 years

• Options:Quinolone otic drops (Ofloxacin /

Ciprofloxacin)• Efficacy has not been studied in children

with AOM & acute perforation• Oral therapy is always preferred

Complications of Otitis MediaRisks for complications associated with otitis

media:

• Increase if an acute episode of otitis media persists longer than 2 weeks.

• Increase if symptoms recur within a 2-3 week period.

• Decrease with early diagnosis and effective antibiotic treatment.

Complications of Otitis MediaIntracranial complications are uncommon in developed

counties but are a concern where access to medical

care is limited. They develop and spread:

• Through vascular channels.

• By direct extension.

• Through preformed pathways such as the round

window.

Extracranial complications are direct sequelae of:

• Localized acute inflammation, or

• Chronic inflammation.

Complications of Otitis Media

• Hearing loss:

Temporary: hearing loss of 25 to 30dB for

several months due to OME; risk of impaired

language development, vestibular, balance,

and motor dysfunctions.

Permanent: damage to the tympanic

membrane or other middle ear structures,

resulting in vertigo or facial weakness.

Complications of Otitis Media

• Adhesive otitis media: abnormal healing in inflamed

middle ear. Irreversible thickening of the mucus

membranes causing impaired movement of the

ossicles and possible conductive hearing loss (e.g.,

tympanosclerosis).

• Chronic suppurative otitis media: chronic otorrhea

through a perforated TM; the cycle of inflammation,

ulceration, infection, and granulation tissue

formation may destroy surrounding bony margins

and ultimately lead to various complications.

Complications of Otitis Media• Postauricular abscess: the most common extracranial complication.

• Tympanic membrane perforation due to increased middle ear

pressure.

• Meningitis: AOM is the most common cause of this intracranial

complication.

• Cholesteatoma: cystlike lesions of the middle ear that may erode

the ossicles, labyrinth, adjacent mastoid bone, and surrounding soft

tissues.

• Mastoiditis: inflammation as an extension of acute or chronic OM,

causing necrosis of the mastoid process and destruction of the bony

intercellular matrix.

Complications of Otitis Media• Facial nerve paresis

• Labyrinthitis: intratemporal complication

• Labyrinthine fistula

• Temporal abscess

• Petrositis: intratemporal complication

• Intracranial abscess

• Otitic hydrocephalus

• Sigmoid sinus thrombosis or thrombophlebitis

• Encephalocele

• CSF leak

Signs of possible impending complication:

• Sagging of the posterior canal wall

• Puckering of the attic or epitympanic recess

• Swelling of the postauricular areas with loss of the skin crease

• Persistent headache and/or fever

• Tinnitus

• Stiff neck

• Visual or other neurologic symptoms

• Severe otalgia

• Vertigo

• Lethargy

• Nausea and vomiting

• Fetid otorrhea

Signs or Symptoms of complication: Intracranial

• Fever associated with a chronic perforation

• Lethargy

• Focal neurologic signs (e.g., ataxia, oculomotor

deficits, seizure)

• Papilledema

• Meningismus

• Altered mental status

• Severe Headaches

Signs or Symptoms of complication:Extracranial

• Fever associated with a chronic

perforation.

• Postauricular edema or erythema.

Patient Education

• Explain the natural history of acute otitis media.

• Explain the benefits of using analgesics to treat ear

pain. Do not use longer than 3 days for pain without

consulting healthcare professional.

• Explain to parents topical analgesics must not be

used if the tympanic membrane ruptures.

• Explain the use of antibiotics in the management of

otitis media and implications of antibiotic-resistant

bacteria in AOM.

Patient Education• Provide parent with extensive information about

antibiotic overuse.

• Explain signs and symptoms of allergic reaction

to antibiotics and to report to healthcare provider

immediately.

• Explain that symptoms should decrease in 24-72

hours with the use of analgesics and/or

antibiotics.

• Explain that persistent otalgia, fever, and other

systemic symptoms past 72 hours should be

reevaluated by healthcare provider.

Patient Education

• Educate regarding the signs and symptoms of

clinical deterioration.

• Educate on preventable risk factors.

• Educate parents and patients regarding the

problem of drug-resistant bacteria and the need to

avoid the use of antibiotics unless absolutely

necessary.

• Explain the entire course of the prescription of

antibiotics must be completed.

Patient Education• Measure body temperature via oral, rectal,

or axillary methods. Transtympanic measurements of temperature in children with middle ear effusions may be inconsistent.

• Heat packs to affected ear may help relieve discomfort.

• Saltwater nasal spray or rinses may decrease congestion.

• Elevating head of crib may facilitate drainage.

Patient Education

• Do not use Q-tips in ears.

• Keep follow-up appointments until the

tympanic membrane is normal. Middle ear

effusion may persist for several weeks,

affecting speech and language development.

• AOM treatment failure requires referral to

otolaryngologist.

Prevention Measures

• Identify and treat underlying conditions that

predispose the child to AOM. This includes:

1. Immune deficiencies: e.g., IgG subclass

deficiency, hypogammaglobulinemia,

granulocyte defects.

2. Anatomic abnormalities: e.g., craniofacial

abnormalities, such as micrognathia, or palatal

clefts.

Prevention Measures

• Breast feed infants: breastfeeding provides for the

transfer of protective maternal antibodies to the

infant; bottle-fed infants have a higher incidence

of AOM than breast-fed infants, probably due to

feeding position during bottle-feeding, which

facilitates the reflux of milk into the middle ear.

• Reduce or eliminate pacifier use, especially after 6

months of age.

Prevention Measures

• Minimal exposure to group settings or daycare

setting with few children.

• Avoid or eliminate bottle-propping.

• Avoid feeding infants in supine position.

• Infection can spread more easily through the

eustachian canal of infants who spend most of

the day in the supine position.

• Avoid exposure to passive tobacco smoke.

Prevention Measures

• Chewing at least 3-5 sticks a day of Xylitol chewing

gum may reduce recurrence rate (if age

appropriate). Xylitol is a sugar found in fruits and

the bark of birch trees that has bacteriostatic

effects against S. pneumonia and interferes with

bacterial adhesion to mucous membranes. Side

effects include excessive gas and diarrhea.

Prevention Measures

• Annual influenza vaccine, especially in high-risk

children who attend day care.

• Early treatment of influenza with the antiviral

oseltamivir may reduce OM.

• Immunization with heptavalent pneumococcal

conjugate vaccine (PCV7 or Prevnar) may reduce the

incidence of AOM caused by S. pneumoniae.

• Consider tympanostomy tube placement for

prevention of recurrent AOM.

References

• American Academy of Pediatrics and American

Academy of Family Physicians (2004). Diagnosis

and management of acute otitis media. Clinical

practice guideline. Retrieved from

http://aappolicy.aappublications.org/cgi/reprint/pedi

atrics;113/5/1451.pdf

• Burns, C.E., Dunn, A.M., Brady, M.A., Starr, N.B. &

Blosser, C.G. (2009). Pediatric primary care . (4th

ed.). St. Louis, MO: Saunders/Elsevier

References

• Donaldson, J. (2010). Middle ear, acute otitis media,

medical treatment. Retrieved from

http://emedicine.medscape.com/article/859316-overview

• Eaton, D. (2009). Complications of otitis media.

Retrieved from

http://emedicine.medscape.com/article/859316-overview

• Greydanus, D., Feinberg, A., Patel, D., & Homnick, D.

(2008). The pediatric diagnostic examination. NY:

McGraw-Hill.

References• Klein, J. & Pelton, S. (2011). Acute otitis media in

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References

• Leskinen, K. (2005). Complications of acute otitis

media in children. Current Allergy and Asthma

Reports, 4, 308-312. Retrieved from

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