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Acute
Otitis
Media
and Otitis Media with Effusion
Dr.
Joel Schwab
Acute otitis media (AOM)
is defined
as an inflammatory process of the middle ear associated with an
effusion.
It is the most common childhood infection for which antibiotics are
prescribed,
representing one of the most frequent reasons for visits to the
pediatrician with
an estimated expenditure of $350 per child with AOM, totaling
approximately
$2.8 billion/year in the U.S. Almost
all
children
will
have one episode of AOM by 7 years of age; however, it is
an unusual
finding in older children and adults. The highest incidence is between
6-13
months of age during the winter season. In
the past 20 years, there has been three times the number
of visits to pediatrician's offices for ear infections. The placement
of
ventilating tubes into the middle ear is the second most frequently
performed
surgical procedure in the United States behind circumcision. The management guidelines below are based
on AAP/AAFP joint clinical guidelines from May 2004, although new AOM
management guidelines are currently in preparation by the AAP.
Risk factors
- First episode before 6
months of age may be related to anatomical abnormalities or minor
immunologic deficiency.
- Family history of
frequent ear infections.
- Formula feeding. Breast
feeding allows for passive transmission of antibodies, typically with
breastfeeding > 3mos.
- Anatomical variations-
cleft palate, Eustachian tube abnormalities, nasopharyngeal tumors,
Down Syndrome
- Altered immune system:
HIV, immune suppression secondary to drugs, IgA deficiency,
Kartagener's syndrome
- Exposure to smoke,
allergens. Increased exposure in daycare
centers.
- Native Americans and
Eskimos, Whites > African-Americans
- Males
- Allergic rhinitis
- Bottle propping
Pathogenesis
- Normal Eustachian tube
function
- Equalizes pressure
between the middle ear and atmosphere-middle ear pressure slightly
negative normally
- Protects the middle ear
from nasopharyngeal secretions and sounds
- Drains secretions from
the middle ear into the nasopharynx
- Eustachian tube in
infants is shorter and at a greater angle than in older children
- Eustachian tube
obstruction leads to negative pressure within the middle ear and
transudation of capillary fluid into the space.
- Functional obstruction:
supporting structures of the Eustachian tube in infants are not well
developed.
- Extrinsic obstruction may
be due to tumors or enlarged lymphoid tissue.
- Inflammatory obstruction:
viral infections, especially RSV and Influenza, may increase the
vulnerability to AOM due to obstruction secondary to inflammatory
changes.
Microbiology
- Streptococcus pneumoniae
(35-40%): The least likely to resolve spontaneously. The highest
incidence of antibiotic resistance is in daycare attendees and those
with prior exposure to antibiotics within the last 1-3 months. The introduction of Prevnar has resulted in a decrease
incidence of AOM by 34% for culture-confirmed
pneumococcal episodes, and by 57% for serotypes contained in the
vaccine, with a shift towards predominantly non-typable H. influenzae. However, there may be a new shift back towards
S. pneumo with non-vaccine serotypes. Further
surveillance
with
the introduction of PCV13 is needed.
- Non-typable Hemophilus
influenzae (20-25%): may be associated with conjunctivitis. Frequently
will resolve without antibiotic treatment.
- Moraxella catarrhalis
(5-20%): Often cures spontaneously. Usually beta-lactamase resistant.
- Group A beta hemolytic
strep/Streptococcus pyogenes (2-3%)
- Staphylococcus aureus and
Mycoplasma are unusual pathogens.
- Viral causes <10%. The
incidence may be higher if PCR were done on all specimens. Often
associated with bacterial infections. The presence of viruses may
promote bacterial suprainfection, impair Eustachian tube function, and
destroy normal epithelial cell barriers.
- Sterile middle ear fluid
may result from prior antibiotic treatment, Mycoplasma or Chlamydia
infections, anaerobes and improper collection of specimens.
- Nasopharyngeal cultures
are not indicated. They are and not specific for middle ear pathogens.
- Newborns have an
increased incidence of Group B strep and gram-negative organisms.
Symptoms
- Often there is a history
of a preceding URI. There may be fever, irritability, ear
pulling,, vomiting, diarrhea, and pain on swallowing.
- The older child will
complain of ear pain and the younger child may awake at night with some
discomfort.
- Otorrhea: spontaneous
rupture of the tympanic membrane
- Decreased hearing
- Vertigo, nystagmus,
tinnitus, and facial paralysis are unusual presenting symptoms.
- Eye drainage: infections
secondary to non-typable H. influenza are often associated with
conjunctivitis
Diagnosis: A symptomatic child with
a red,
bulging, tympanic membrane that doesn't move with insufflation.
- A clinical diagnosis
based on 3 main criteria: signs of acute infection, evidence of middle
ear inflammation, evidence of middle ear effusion (MEE)
2.
AOM diagnosis is NOT
associated with occurrence, duration, or severity
of parent-reported symptoms (ear pain, ear rubbing, fever). Over-diagnosis is
commonly secondary
to relying on redness, not using pneumatic otoscope, relying on past
history,
parental pressure, and rechecking too soon after treatment.
- Pneumatic otoscopic
examination is the most reliable tool to diagnose AOM. It is 95%
sensitive and 80% specific. Must establish a tight seal and remove
cerumen. Signs of middle ear inflammation (redness) and
signs of middle ear effusion (cloudy, immobile, bulging) are suggestive
of AOM but the accuracy/precision of these findings have not been
determined.
- Assessment may be
hindered by the presence of cerumen, a poor light source, failure to
establish a tight seal, mistaking the canal wall for the drum, and
narrow canals
- Redness of the tympanic
membrane may be associated with URIs, crying, sneezing, and following
cerumen removal.
- Tympanometry- tests
the
condition
of the middle ear and mobility of the eardrum using
variations of air pressure in the ear canal. Useful
for
teaching
and confirming presence of fluid that you diagnose with
pneumatic otoscope. Better negative predicative value. 50% of abnormal
tympanograms will have normal ears. Majority of normal tympanograms
will have normal ears.
- Tympanocentesis- drainage of fluid from the middle ear using a small gauge
needle.
- useful to relieve
pain
- in infants,
immunodeficient children, and treatment failures a means to obtain
organism for culture and sensitivity.
Antibiotic Therapy
- Greater than 60% will
resolve spontaneously within 10 days but there is no clinical means to
distinguish those that need to be treated. In patients
older than 6 months without severe symptoms, current studies are
controversial regarding immediate antibiotic treatment vs. observation
for 48-72 hours with possible delayed antibiotic treatment if symptoms
persist. Immediate treatment appears to have a
modest benefit over delayed treatment and placebo, but with a higher
incidence of side effects (diarrhea and rash).
- Amoxicillin is the first
drug of choice for uncomplicated AOM, and there is no evidence of
initial use of higher-cost antibiotics for uncomplicated cases. The
initial
dosage
amoxicillin should be 80 to 90 mg/kg/day.
Amoxicillin has excellent middle ear penetration and despite penicillin
resistance, levels may be high enough to kill many bacteria. It is
85-94% effective, tastes good, is inexpensive, has a narrow spectrum of
activity, and has a good safety record. Ampicillin can also be used and has been studied extensively
as well as a first line drug of choice for treatment of AOM.
- If the child is not
clinically improved on antibiotics within 48 to 72, re-evaluation of
the child is warranted, as there may be a poor response to
Amoxicillin. This occurs in 10% of cases and more frequently when
viruses are present. Alternative treatment
should be effective against drug resistant Streptococcal pneumoniae and
beta-lactamase producing organisms. This would include
amoxicillin-clavulanate (Augmentin), PO cefuroxime (Ceftin) Cefpodoxime
(Vantin), Cefuxime (Supra), PO Cefaclor, or IM ceftriaxone. PO Azithromycin has been found to
have equal efficacy to PO Cefaclor, although 10 days
amoxicillin-clavulanate was more efficacious than 5 days of
Azithromycin.
- If there is no response
after initiating second-line antibiotics, 3 daily IM injections of
Ceftriaxone or Clindamycin PO have been tried. It is important to
remember that Clindamycin is not effective against beta-lactamase
producing organisms. Tympanocentesis should be considered to obtain
cultures.
- There is an increased
incidence of drug resistance in daycare attendees, recent users of
antibiotics, and patients on prophylactic antibiotics. Often
penicillin-resistant pneumococci will also be resistant to
trimethoprim/sulfisoxazole, erythromycin, and cephalosporins.
- Antibiotic choice must
take in consideration cost, compliance and convenience of dosing
schedule, taste, and bacterial resistance in the community or
region.
- Symptomatic otitis media
greater than 2 weeks after completion of therapy should be considered
to be a new pathogen and Amoxicillin may be started.
- Current evidence suggests
that there is no benefit of long-term course of antibiotics (over 7
days) vs short-term course of antibiotics (less than 7 days). Current studies also suggest limitation of
antibiotic use to prevent further development of antibiotic resistance.
Management
1.
Active monitoring for
recurrence of
symptoms, persistent infection, OME. MEE
may still be present in 60% at 2 weeks, 50% at 4
weeks, 20% at 8
weeks and 15% at 90 days. Children who are asymptomatic should be
checked in
3-6 weeks.
2.
Adjuvant therapy: Pain
relief,
including local drops, analgesics, heating pad, warm oil. Most studies
have shown
that antihistamines and decongestants do not facilitate cure nor
decrease the
incidence of developing OME.
3.
Instructions to parents
- When to follow-up
- Directions on how to give
the medicine including the importance to complete the entire
prescription
- Tell parents that the
medicine will not help URI symptoms
- Symptoms/signs that the
medicine is not working and any complications that they should notify
you about.
- Tell the family that pain
may persist for up to 24 hours after starting treatment.
- Influenza vaccine- if
infant had many bouts the previous year, may consider vaccine to
decrease the incidence of viral illness.
- Xylitol, a sugar
substitute, has been shown to inhibit the growth of pneumococcus. Study
of 5 year olds who chewed gum containing xylitol, had a decreased
incidence of AOM.
- Prophylaxis- use of prophylactic
antibiotics may decrease the frequency of AOM. Data for appropriate
dosage and timing is not available. Studies have demonstrated that
prophylaxis is a good as ventilating tubes in preventing AOM. May
induce increase of resistant organisms and some studies have shown no
benefit. Amoxicillin and sulfasoxazole recommended if you choose to use
prophylaxis.
- If the child presents
with otorrhea, treatment is the same as AOM without perforation, but
need to reassure parents that resolution doesn't differ and there are
no long-term complications.
Complications
- Hearing Loss: usually
conductive and temporary. There have been rare cases of sensorineural
hearing loss. If there are adhesions of the drum, tympanosclerosis, or
ossicle changes, may have permanent loss of hearing.
- Perforation: May be
associated with AOM. Use same antibiotics as without perforation. Some
recommend antibiotic/corticosteroid drops to prevent external otitis.
Perforations usually heal by themselves. If there is a chronic
perforation, may need surgical repair but this is uncommon.
- Cholesteotoma: presence
of keratinized material in the middle ear. There is an odorous chronic
drainage. There may be bony destruction and invasion of the cranium.
- Mastoiditis: infection of
the mastoid process, now quite rare with antibiotic therapy. Due to inflammation of the mastoid air cell. Treatment includes placement of tympanostomy
tube and IV antibiotics usually necessary. If
an
abscess
develops in the subperiostal tissue, surgery may be
required.
- Otitic hydrocephalus: a
rare complication of AOM. Characterized by
increased intracranial pressure with normal CSF analysis.
- Intracranial abscesses
- Sinus thrombosis
- Facial nerve
paralysis
OTITIS MEDIA WITH
EFFUSION (OME)
- Definition- A common
condition of childhood characterized by the presence of fluid in the
middle ear without signs or symptoms of infection. In some
instances, aspiration may yield the presence of bacteria.
- Because of association
with hearing loss and concern of this relationship to learning, speech,
and other developmental abnormalities, physicians are anxious to treat
OME.
- Risk Factors- Same as
AOM (cleft palate, Down’s syndrome, etc)
- Diagnosis-
- May be incidental
finding
- Seen following treatment
of AOM
- Present with decreased
hearing, "discomfort", or behavioral changes.
- Pneumatic otoscope is
recommended for assessing the middle ear. Examination will have
decreased mobility of TM, yellow-orange fluid, may have air fluid
level, and drum may appear thickened. Hearing evaluation may be used in
diagnostic evaluation.
- Tympanometry
- Natural history
- Most of the cases of OME
will resolve spontaneously
- Fluctuating clinical
symptoms that vary with time and age
- Some children will
experience transient hearing loss
- Intervention is needed
due to the effects of prolonged hearing loss
- Complications
- High frequency hearing
loss
- Difficulty discriminating
sounds
- Decreased expressive
language skills (indistinct speech, language development
delay)
- Decreased attention span
- Poor educational progress
- Balance difficulties
- Recurrent infections
(AOM, URIs)
- Therapeutic Interventions
1-3 year olds -US Agency on Health
Care Policy and Research
- Once OME is diagnosed,
guidelines suggest active observation for 3 months with interval
rechecks of the status of the effusion.
- Treatment with
antibiotics. Studies have shown a slight advantage in resolution of the
fluid with antibiotic treatment.
- Environmental risk factor
control counseling
- After 6 weeks, hearing
evaluation can be considered. Also
consider
other
etiologies for hearing loss (sensorineural, permanent
conductive, non-organic causes).
- After 3 months of
effusion, evaluate hearing loss, speech and language development. If
there is significant (>20 decibel) bilateral hearing loss, consider
antibiotic treatment or bilateral tympanostomy tubes and environmental
control counseling (smoking, daycare attendance). Interventions
such
as
bilateral tympanostomy tubes should be withheld until
persistence of bilateral OME and hearing loss is confirmed for at least
3 months.
- Tympanostomy tubes have
been shown to have a 7-9 dB improvement in hearing loss when placed
unilaterally, and 4-10 dB when placed bilaterally.
Children with tubes placed should have regular
hearing checks to ensure that hearing remains normal.
- However, placement of
tympanostomy tubes remains controversial, as no benefits in
developmental outcomes has been shown for children with previous tube
placement between 3-6 y/o and 9-11 y/o.
- There is no role in the
treatment of OME for Antihistamines/decongestants, topical or systemic
steroids, adenoidectomy, or tonsillectomy. Current
guidelines do not recommend adjuvant adenoidectomy with bilateral
tympanostomy tube placement without signs/symptoms of
persistent/frequent URIs.
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