What are the key clinical features that differentiate otitis externa from otitis media in children?

Key clinical features differentiating otitis externa from otitis media in children include the site and nature of symptoms, examination findings, and associated systemic signs.

Otitis externa primarily affects the external auditory canal and is characterised by ear pain that worsens on manipulation of the pinna or tragus, ear canal tenderness, and often visible inflammation or swelling of the external ear canal skin. There may be discharge from the ear canal, but the tympanic membrane typically appears normal on otoscopy.

In contrast, otitis media involves infection or inflammation of the middle ear space behind the tympanic membrane. Children with otitis media often present with ear pain that is less affected by external ear manipulation, fever, and sometimes hearing difficulties. Otoscopic examination reveals a bulging, erythematous, or opaque tympanic membrane, sometimes with effusion or perforation. Systemic symptoms such as fever and irritability are more common in otitis media.

Otitis media with effusion (OME), a subtype, presents with hearing difficulties, delayed speech, or behavioural changes without acute pain or fever, and the tympanic membrane may appear dull or retracted with visible fluid levels or air bubbles. OME is less likely to present with the external ear canal inflammation seen in otitis externa.

Thus, the key differentiators are the site of pain and tenderness (external canal in otitis externa vs. middle ear in otitis media), otoscopic findings (normal canal but inflamed skin in otitis externa vs. abnormal tympanic membrane in otitis media), and systemic features (more common in otitis media) ¹.

Recent literature on intractable otitis media highlights the complexity of middle ear pathologies but does not alter these fundamental clinical distinctions (Yoshida, 2023).