What condition results in a bulging tympanic membrane (TM)?

A bulging tympanic membrane (TM) is most commonly associated with acute otitis media. This condition refers to an infection in the middle ear that leads to the accumulation of pus or fluid behind the TM. As this fluid builds up, it can create pressure that causes the TM to bulge outward. This is often accompanied by symptoms of ear pain, fever, irritability, and sometimes hearing loss.

In contrast, while chronic otitis media might also result in abnormalities of the TM, it is typically characterized by a more persistent state of inflammation that may not always lead to a pronounced bulging. Mastoiditis, which can occur as a complication of untreated acute otitis media, is an infection of the mastoid bone and may not directly cause bulging of the TM. Middle ear effusion refers to the presence of fluid in the middle ear without infection and can lead to a retracted TM or changes in its appearance, but does not typically result in a bulging membrane.