Acute Otitis Media (AOM) can have viral or bacterial origin. The commonest bacterial causes include: Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Group A streptococcus (strep.pyogenes or GAS).
Co-infection is possible.
Who do you treat with antibiotics?
High grade fever (>/= 39 degrees Celcius)
Moderately to severely unwell child
No improvement within 48h (as with viral AOM, we usually see improvement within this time frame)
Those who have bulging tympanic membrane (TM)
Middle ear effusion (MEE) – reduced mobility of tympanic membrane has high sensitivity an specificity for MEE.
Perforated tympanic membrane with purulent drainage (otorrhea) – commonly caused by GAS
Erythematous or yellow tympanic membrane
Of note: air fluid level visible on TM without erythematous TM is not consistent with AOM.
Why do you treat?
Bacteria such as strep. pneumoniae can become invasive and there can be complications.
Complications include (although, rarely at presentation):
1) Acute mastoiditis (commonest complication) – clinically, this may manifest as pain or swelling over the mastoid bone. Ensure IV antibiotics, imaging to delineate extent of infection, and surgical consultation for potential intervention.
2) less common:
acute facial (CN VII) nerve palsy – associated with temporal bone inflammation
abducens (VI) nerve palsy – associated with petrous bone inflammation or infection (Gradenigo’s syndrome)
labyrinthitis- associated with cochlear space spread
venous sinus thrombosis of transverse, lateral or sigmoid venous sinuses
If infection is in keeping with viral:
Do not treat with antibiotics due to increased rates of resistant bacterial infections.
Amoxicillin cover strep. pneumonia and GAS, and has good middle ear penetration. It does not have good cover for H.influenzae or M.catarrhalis, but these infections tend to self-resolve within a few hours. Amoxicillin also has good middle ear penetration.
Amoxicillin 75-90 mg/kg/day divided twice per day (capsules/suspension)
Amoxicillin 45- 60 mg/kg/day divided there times per day (capsules/suspension)
For clinical cure: amoxicillin should be adequate for over 50% o the day, therefore twice per day regimens require higher dosing.
If penicillin allergic:
second generation cephalosporin such as cefuroxime, cefprozil, or third generation cephalosporin such as ceftriaxone.
cefuroxime axetil – 30mg/kg/day divided twice or three times/day (tablet/suspension)
ceftriaxone – 50mg/kg IM/IV daily for three days
What if the patient does not entirely appear to have bacterial features, as above, and it has only been one day since symptoms started, and they appear mild to moderately affected, but are eating/drinking well, no otalgia, and have lower grade temps?
One option is to “watch and wait”, and have the patient return the following day to be re-assessed.
Another option is to provide a prescription for antibiotics, so if the child becomes more febrile, more ill, or increasingly impacted by otalgia or other symptoms. It is always important to counsel on signs and symptoms to return to seek medical attention, however.
Other conditions to consider:
H. influenzae and M. catarrhalis if there is otitis conjunctivitis syndrome. In this case, a macrolide/azalide should be administered, although they are bacteriostatic, and as such, have less bactericidal activity than B-lactams (penicillins/cephalosporins). In this case, amoxicillin/clavulin or cefuroxime should be administered.
If treated with amoxicillin in the last thirty days, there is relapse or no response –> start amoxiclav.
If the child is 2 years of age or older, with uncomplicated AOM:
5 days of antibiotics
If the child is under 2 years of age (i.e., 6 months to 23 months):
10 days of antibiotics
Over 6 months, with perforated TM or recurrent AOM:
This is a brief summary of the CPS Statement, which can be found below: