A 2-year-old presents to ED with pyrexia – he’s pulling at his ear constantly in the waiting room. You know where this heading, but are you supposed to treat him with antibiotics or not?
Do you know the difference between acute otitis media (AOM) and otitis media with effusion?
Treat acute otitis media (AOM) < 2 yrs old with antibiotics
Treat AOM > 2 yrs if systemically unwell
Re-evaluate at 48 hours if needed
Don’t forget the pain relief
What is otitis media?
Otitis media is a general term that has been used to describe multiple disorders of middle ear inflammation
Acute otitis media (AOM)
Otitis media with effusion (OME)
Chronic otitis media (COM)
Establishing the diagnosis is important as antibiotic treatment is not recommended for OME
The definition of acute otitis media requires three equally important components, which must all be present.
- Acute onset (<48 hours) of signs and symptoms
- Middle ear effusion (MEE)
- Signs and symptoms of middle ear inflammation (at least one of fever, otalgia, irritability in an infant; red tympanic not due to crying or fever)
Who gets it?
There is considerable overlap between presenting signs and symptoms of upper respiratory illnesses and acute otitis media, especially in the preverbal child.
The peak incidence is between 6 and 18 months of age. Neonatal acute otitis media is uncommon. Most effusions of the middle ear in this age are sterile and develop in utero.
Prevention of the disease burden is possible through the use of newer vaccines such as the contemporary pneumococcal vaccine that includes protection from seven serotypes of Streptococcus pneumoniae.
What are the most common bugs?
Bacteria from the nasopharynx are the most common cause of acute otitis media and can be isolated from middle ear fluid in a majority of cases. The most common pathogens in the post-pneumococcal vaccine era are:
- Non-typeable Haemophilus influenzae (56%)
- S. pneumoniae (31%)
- Moraxella catarrhalis
- Mycoplasma may cause a bullous myringitis
Neonates may be affected by gram negative organisms and Staph aureus.
The role of viruses is unclear.
These data were obtained in the post-pneumococcal vaccine era and represent a change from before this vaccination program was initiated. Of importance is a major change in the increased prevalence of β-lactamase organisms such as M. catarrhalis (almost 100%) and non-typeable H. influenzae (35% to 40%).
What is otitis media with effusion (OME)?
OME usually follows an episode of acute otitis media, and both are processes of the same disease continuum. OME may persist for weeks to months after an episode of acute otitis media.
Close to 90% of episodes of OME resolve spontaneously after an acute otitis media episode is diagnosed.
Guidelines recommend watchful waiting without the immediate use of antibiotics for children with uncomplicated otitis media with effusion.
Children with permanent hearing loss, craniofacial anomalies, or underlying speech delays may receive immediate antibiotics or have close outpatient follow-up by the primary care clinician.
Should I treat it?
Consensus guidelines strongly recommend the treatment of pain associated with acute otitis media.
Antibiotics are not analgesics so prescribing only an antibiotic for the treatment of acute otitis media is inappropriate.
Ibuprofen and paracetamol are the primary systemic analgesics and antipyretics used to treat acute otitis media. In one randomized trial comparing ibuprofen, acetaminophen, and placebo, only ibuprofen was found to be superior to placebo.
High-dose amoxicillin, 80 to 90 mg/kg PO per day divided into two daily doses for 5 to 7 days, is the first-line recommended antibiotic for the treatment of uncomplicated acute otitis media.
The higher dose achieves concentrations in the middle ear that exceed the minimum inhibitory concentration for highly resistant forms of S. pneumoniae (the most common bacteria found in acute otitis media), M. catarrhalis and non-typeable H. influenzae, although the addition of clavulanic acid increases the likelihood of vomiting and diarrhoea.
IM ceftriaxone for three daily doses may be considered if children cannot tolerate oral medications. Children with a known allergy to the penicillin class may consider the use of a macrolide agent, such as azithromycin.
A 10-day course of antimicrobials has been recommended for decades without any evidence to support an exact duration of therapy. Shortened treatment regimens (5 to 7 days) may reduce resistance to antibiotics and reduce side effects by decreasing total drug exposure.
What is the evidence for treatment?
Two randomized double-blinded placebo-controlled trials of young children diagnosed with AOM
Hoberman et al, University of Pittsburgh
Tahtinen et al, Turku University Hospital in Turku, Finland
In children between 6 months and 2 years of age with certain AOM, the use of antibiotics result in faster recovery and less treatment failure (reduced by 42-62% in the severe group)
Although a majority of patients receiving placebo also recovered spontaneously (53% in Hoberman et al, 55% in Tahtinen et al.), a physician cannot predict at the onset of illness which patients will improve without antibiotics.
Even in patients with non-severe illness, antibiotics were associated with a decrease rate of treatment failure.
Antibiotics are advised for…
All infants under 6 months
Age 6 months – 2 years with certain diagnosis or uncertain diagnosis and severe illness
Age 2 years and over with certain diagnosis and moderate/severe illness
Age 6 months onwards with uncertain diagnosis and follow up assured observation without antibiotics is an option for mild illness (no systemic features) with re-evaluation at 48 hours & antibiotics if no improvement
Summary of Antibiotic Choice
1st line treatment is high dose amoxicillin, due to reduced side effects and drug exposure
Whether amoxicillin alone will yield the same benefit is unclear, although in previous studies, 80% were successfully treated with amoxicillin
In severe disease, amoxicillin-clavulanate is the preferred first line
What are the complications of otitis media?
As in the photo below, there can still be a perforation that does not heal within a few weeks. This is considered to be a natural myringotomy and usually heals well. GP follow-up is all that is required.
Facial nerve palsy
The facial nerve descends over the posterior wall (mastoid) of the middle ear and can be affected by otitis media.
The infection can extend into the mastoid (posterior to the middle ear). It can cause bone destruction, brain abscess, meningitis, VI and VII nerve palsies, lateral venous sinus thrombosis. It is very unlikely if the ear exam is normal as it is linked to otitis media.
A CT is advised along for IV antibiotics (usually ampicillin)
Cystic cholesterol lesions are linked to chronic OM and can erode local structures.
Bacteraemia occurs in 3%.
Conductive deafness can follow a persistent effusion.
Resolution and follow-up
Fever and ear pain are expected for 24 to 48 hours after an ED evaluation. If symptoms persist after 72 hours of antibiotics, reevaluation is needed. Routine, scheduled visits are not recommended for uncomplicated acute otitis media if symptoms have resolved.
There should be obvious by 2-3 days. Treatment failure may suggest the wrong diagnosis, development of a complication or the presence of a resistant organism. If the initial treatment was amoxicillin, change to amoxicillin/clavulanate.
All children should be reviewed by the local doctor at 2 weeks for the presence of a persistent effusion (glue ear) or healing of the tympanic membrane (if ruptured).
ENT consultation is advised for children with persistent hearing loss or speech delay, chronic effusion for more than 3 months, frequent episodes of otitis media or underlying pathologies such as cleft palate or adenoidal hypertrophy.
Hawke Library – otitis media guide