Otitis media is the most commonly diagnosed illness in childhood. This infection occurs in half of all infants before their first birthday and in 80% by their third birthday.
Acute otitis media
consists of inflammation of the middle ear. Fever and ear pain are the most common acute symptoms. Irritability, anorexia, vomiting, and diarrhea may also be present.
Acute otitis media is most common in children of age 6 months to 3 years. The majority of children have had at least one episode of acute otitis by age 3. It is uncommon after age 8. The incidence rises during winter and declines during summer.
Otitis media with effusion
consists of a chronic bacterial infection persisting more than 2 weeks, manifesting as an asymptomatic middle-ear effusion. The syndrome usually develops after an acute otitis media.
The most common bacterial pathogen in all age groups is Streptococcus pneumoniae, causing 40% of effusions. The next most common is non-typable Haemophilus influenzae, causing 20% of effusions.
caused bybeta-lactamase occurs in 30-50% of H influenzae and up to 80% of M. catarrhalis.
Penicillin-resistant S. pneumoniae
results from bacterial alterations in penicillin-binding proteins, rather than beta-lactamase. Highly resistant strains are resistant to penicillin, trimethoprim/sulfamethoxazole (TMP/SMX), and third-generation cephalosporins.
Diagnosis A. Acute otitis media
The position, color, translucency and mobility of the tympanic membrane should be assessed. The normal eardrum is translucent, and landmarks should be visible through the eardrum. A cloudy opacified tympanic membrane in children is often associated with a middle-ear effusion. Erythema of the eardrum alone is often the result of a viral infection or crying.
In otitis media, the tympanic membrane is dull and bulges externally, losing its concave contour and light reflex. An air-fluid level or air bubbles may sometimes be visualized behind the tympanic membrane.
Reduced or absent mobility of the tympanic membrane with air insufflation is the most specific sign of acute otitis media.
Otitis media with effusion.
In the absence of symptoms or signs of acute illness, evidence of middle- ear inflammation indicates that an otitis media with effusion is present. Typical findings include diminished tympanic membrane mobility and visualization of air-fluid levels.
Treatment of acute otitis media
Oral antibiotics should be prescribed for 10-14 days.
Amoxicillin is the first-line antimicrobial agent for treating AOM. For patients with treatment failure after three days of therapy, alternative agents include oral amoxicillin-clavulanate, cefuroxime axetil, and intramuscular ceftriaxone.
Streptococcus pneumoniae causes 40-50% of all cases of AOM. This bacterium has reduced susceptibility to penicillin in 8-35% (2-4% highly resistant) of isolates and reduced susceptibility to third-generation cephalosporins in 10% of isolates (about 4% highly resistant).
Cefuroximeaxetil(Ceftin)andamoxicillin-clavulanate (Augmentin) orally, and ceftriaxone (Rocephin) intramuscularly, are useful as second-line drugs for treatment failure after three days of therapy.