Acute Otitis Media

Question 1

Prevalence of AOM?

Answer 1

75% experience 1+ AOM before starting school

Question 2

Factors predisposing to more AOM in kids?

Answer 2

More viral infections (viral infections cause ET dysfxn or obstruction - impaired mucociliary clearance)

ET shorter and more horizontal

Question 3

Risk factors for AOM?

Answer 3

• Young age
• Frequent contact with other children
• Household crowding, cigarette smoke
• Orofacial abnormalities (cleft palate)
• Pacifier use
• Shorter duration of breastfeeding
• Prolonged bottle feeds while lying down
• FHx of AOM
• First Nations/Inuit
• Lower levels of IgA

Question 4

If AOM spontaneously regresses, what organisms are more likely?

Answer 4

• Viruses
• Moraxella catarrhalis
• Haemophilus influenza

(S pneumo, GAS more virulent)

Question 5

3 most common organisms in AOM?

Answer 5

S pneumo, H flu, M cat

less commonly GAS

Question 6

Diagnostic criteria for AOM?

Answer 6

Acute onset of symptoms (otalgia) +

1. Middle ear effusion - decreased mobility, loss of bony landmarks, A/F level
2. Bulging TM

Question 7

What is the most sensitive and specific predictor of MEE associated with AOM?

Answer 7

Impaired TM mobility

- bulging TM also very sens and spec

Question 8

Acute perforation with otorrhea associated with which bacteria?

Answer 8

S. pneumo (S. pyogenes too)

Question 9

Most common complication of AOM?

Other complications?

Answer 9

Acute mastoiditis

CN VII palsy - facial nerve palsy (temporal bone inflammation)
CN VI palsy - failed ipsilateral eye abduction
(petrous bone inflammation)
Labyrinthitis - infection spread to cochlear space
Sinus venous thrombosis
Meningitis

Question 10

What is the NNT if stringent AOM dx criteria are applied?

Answer 10

4

Question 11

Perforated TM with purulent drainage - how to manage?

Answer 11

Treat with 10 day course of abx

Question 12

MEE + bulging TM - how to manage if “mildly ill”?

Answer 12

Mildly ill (mild otalgia, sleep ok, T

Question 13

MEE + bulging TM - how to manage if “moderately to severely ill”

Answer 13

(Irritable, not sleeping, severe otalgia, poor response to abx
OR T > 39 OR >48h of symptoms)

10 days abx (6 mos-2 yrs)
5 days abx (>2 yrs)

Question 14

First line antibiotic for AOM and why?

Answer 14

Amoxicillin

• S. pneumo is >90% susceptible to penicillin (and causes invasive disease)
• Also covers GAS
• Good middle ear penetration
• Narrow abx spectrum
• Unlikely to cover beta-lactamase producing Moraxella and H. flu (but more likely to resolve spontaneously + less common)

Question 15

Amoxicillin dosing?

Answer 15

45-60 mg/kg/day divided TID
OR
80-90 mg/kg/day divided BID
(for adequate middle ear levels for > 50% of the day)

Question 16

Abx if otitis-conjunctivitis syndrome (purulent conjunctivitis)?

Which are causative organisms?

What is another indication to use this antibiotic?

Answer 16

H. flu and M. catarrahalis

Clavulin (beta lactamase inhibitor)
OR
Cefuroxime

Clavulin can also be used for tx with amoxicillin within past 30 days; nonresponse to amoxil

Question 17

Abx choice if hypersensitivity run to amoxicillin?

Answer 17

Cefuroxime or ceftriaxone (if non-anaphylactic)

Macrolide (clarithromycin or azithro if anaphylactic)

Question 18

When to prescribe 10 days vs 5 days of abx?

Answer 18

10 days if = 2 years old, perforated TM, failed initial therapy, recurrent AOM