Define acute otitis media
Presence of inflammation in the middle ear accompanied by the RAPID onset of signs and symptoms of an ear infection
Who does AOM effect commonly? When?
Most common in children and is often preceded by a viral or bacterial upper respiratory tract infection
What encompasses the middle ear?
The Incus, Malleus and Stapes
Seperated from the outer ear by the tympanic membrane
Define otitis media with effusion (OME)?
Presence of fluid in the middle ear without signs and symptoms of an ear infection
Describe the pathophysiology of AOM
Patient has a preceding event (viral URTi)
Inflammation of the respiratory mucosa
Edema obstructs pharyngotympanic tube (Eustachian tube) (poor ventilation and negative middle ear pressure)
Viruses from bacteria from URT enter the middle ear (from where the ear and throat connect)
Microbial growth results in clinical signs of AOM
Describe the anatomical considerations of inflammation and fluid accumulation in the middle ear?
Inflammation and fluid accumulation in the middle ear:
The middle ear is the location of the hearing apparatus
It is seperated from the outer ear canal by the tympanic membrane
Normally the eustachian tube protect the middle ear from nasopharyngeal secretions and provides draingae from such secretions
Describe the etyiology of AOM? Resolution?
70% of bacterial infections occur due to the following pathogens:
S. pneumonaie (25-50%) - 20% spontaneous resolution
H. Influenzae (15-30%) - 50% spontaneous resolution
M. Catarhhalis (3-20%) - 75% spontaneous resolution
H. Influenzae and M. Catarhhalis are likely to resolve spontaneously
Up to 50% of AOM cases are due to viral causes listed (rarely fungal) and resolve without antibiotic therapy
- RSV (RSV), parainfluenza viruses, coronavirus, rhinovirus, and adenovirus (Similar organism to viral pharyngitis)
Describe the epidemiology of AOM?
Peak incidence between 6-18 months (< 2 years old - Treat for 10 days, If older than or equal to 2, treat for 5 days)
Common in 6 months- 3 years of age and affects about 70% of children (spreads quickly)
Uncommon after 8 years of age
Recurrent AOM affects about 15-30% of otitis-prone children
How can one distinguish if AOM is likely bacterial?
Likely bacterial if:
- Bulging tympanic membrane that is hemorhhagic or yellow
- Perforation of the tympanic membrane with purulent discharge (otorrhea)
Describe the common symptoms of AOM and other symptoms patients may experience
The 3 most common symptoms include:
1) Otalgia (ear pain)
2) Irritability
3) Fever (absent in 50% of cases)
Patients may also experience nasal congestion, coughing, loss of appetite, vomitting, and otorrhea
Describe the severity of illness of AOM? When is antibiotics needed?
Mild AOM:
- Absence of pain or mild pain
- Alert, responsive, able to sleep
- Oral temp < 39 C without antipyretic
< 48 hours of symptoms
Moderate-Svere AOM - REQUIRE ANTIBIOTIC
- Moderate to severe otalgia
- Tugging on the ear, inability to sleep AND/OR
- Oral Temperature greater than or equal to 39 C AND/OR
Greater than or equal to 48 hours of symptoms
What is the most common complication of AOM?
Acute Mastoiditis - Inflammation and infection of the mastoid bone
AOM is likely if the following are present:
Acute onset (e.g. otalgia)
Middle-ear effusion (MEE/OME - fluid buils up in the middle ear that is not infected)
Middle-Ear Inflammation
What are the methods for diagnosis of AOM?
Visualizing the tymapnic membrane with an otoscope
- Bulging
- Redness/opacity
- Immobility
- Perforation (high-sensitivity for bacterial cause, warranting antibiotics)
Diffrentiational Diagnoses AOM
Otitis mediation with effusion (OME, can last days to weeks after infection has resolved)
Acute otitis externa
Imapcted earwax
Chronic otitis media
Define recurrent AOM
Greater than or equal to 3 episodes in 6 months or greater than or equal to 4 episodes in 12 months
Describe the risk factors for AOM
Age: Children peak between 6 months - 3 years of age
Childcare attendance or presence of siblings in the home
Crowded household
Pacifier Use
Second hand smoke exposure
Orofacial abnormalities (e.g. cleft palate)
Recent episode of influenza/URTi
Indigenous/Inuit/children of First Nations (due to access to care/systemic inequity)
Family history of reccurent otitis media
Low socioeconomic status
Immunocompromised patients
Feeding while lying down, shorter duration of breastfeeding
AOM Goals of Therapy
Resolve signs and symptoms
Eradicate ear infection and sterilize the middle ear
Prevent complications
Avoid inappropriate use of antibiotics
Describe the role of vaccination in AOM?
The annual influenza vaccine is reccomended for all individuals greater than or equal to 6 months, especially those with chronic medical conditions:
- Renal disease, cardiac or pulmonary disorders (e.g. cystic fibrosis, asthma), metabolic disorders (e.g. diabetes), cancer, immunocompromised status, anemia, or neurodevelopmental conditions
The pneumococcal conjugate vaccine is reccomended in children as young as 2 months
Non-typable H. Influenzae strains cause the majority of AOM cases, limiting the effectiveness if the Haemophilus Influenzae type b (Hib) vaccine
Describe the AOM treatment algorithm and referral
When should watchful waiting be considered?
During the first 24-48 hours in children greaater than or equal to 6 months of age with the following:
- Mild Illness
- Uncomplicated AOM , oral temp less than 39 C
- No serious commorbidities (e.g, immunodeficiency, tympanosotomy tubes)
- Guardian can recognize when illness is worsening and return for follow up
For which patients is watchful waiting inappropriate?
< 6 months
Perforated tympanic membrane
Moderate, Severe Presentation:
- irritable, difficulty sleeping, severe otalgia, poor response to antipyretics OR
- sx greater than or equal to 48 hours OR
- Temp greater than 39 C (without antipyretic use)
Otorhhea (ear discharge - any age)
Typamostomy tubes, cochlear implants
Recurrent AOM
Bilateral AOM ( if < 2 years)
medical comorbidities (e.g. craniofacial abnormalities, immunodeficiency)
Unrelaible caregiver or follow up
What are the conditions for watchful waiting?
Option is indicated for patients whose infection is expected to resolve spontaneously
Caregiver should have ready access to clinicians and should return if the child does not improve or worsens anytime within 48 hours
If antibiotic prescription is issued, the parent is asked to not fill the prescription unless symptoms persist or worsen over 24-48 hours
Describe the first line treatment and rationale regarding suceptibility of organisms? What about allergies?
Amoxicillin is considered first line therapy for AOM, as infection is predominately caused S. Pneumonaie
M. Catarhhalis and H Influenzae can be resistant to amoxicillin due to their ability to produce beta-lacatamases, but infection caused by those pathogens is less common and more likely to resolve spontaneously
In patients with a history of penicillin of amoxicillin hypersensitivity, use second or 3rd gen cephalosporins UNLESS the previous reaction was life-threatning (e.g. hypotension, bronchospasms)
- Alternative agents with life threatning hypersensitivity reactions: macrolides (e.g. azithromycin or clarithromycin) or clindamycin –> Less efficacy against S. Penumonaie and H influenzae
