Which condition is characterized by a viral URI that leads to the development of fluid and mucus in the middle ear?

Acute otitis media is characterized by the presence of fluid and mucus in the middle ear, often following a viral upper respiratory infection (URI). During a viral URI, the Eustachian tube can become blocked or dysfunctions, preventing proper drainage and ventilation of the middle ear. This blockage allows fluid to accumulate in the middle ear space, creating an environment that is conducive to bacterial growth, which may lead to infection.

This condition typically presents with symptoms such as ear pain, irritability in children, and in some cases, fever. Diagnosis is confirmed through otoscopic examination, where a bulging, erythematous tympanic membrane may be observed, indicating fluid behind the eardrum.

Other conditions listed, such as acute sinusitis and chronic otitis media, have different pathophysiological mechanisms and may present with distinct clinical features. Acute sinusitis refers to inflammation of the sinuses, while chronic otitis media involves persistent middle ear infections over an extended period. Otitis externa, often known as swimmer's ear, refers to an infection of the outer ear canal and does not involve the middle ear or follow a URI.