Glue ear is common among children after middle-ear infections (otitis media); effusion, produced by mucus cells, occurs in the middle ear and cannot be cleared.
It is a particular problem for young children because of the angle and immaturity of the Eustachian tube, and the supine position in which infants are often placed.
There are thought to be several causes of glue ear, including bacterial and viral infection, allergy, and the presence of stomach acid (and the enzyme pepsin) as a result of gastric reflux.
Andrea Tasker from the University of Newcastle upon Tyne, England, and colleagues investigated reflux of gastric juice as a potential cause of glue ear.
| Pepsin levels in effusions were 1000-fold greater than those in blood.
The investigators measured pepsin concentrations in middle ear effusions from children in Newcastle upon Tyne and Nottingham, England.
Some 45 (83%) of 54 effusions contained pepsin/pepsinogen at concentrations of up to 1000-fold greater than those in blood (used for comparison).
Andrea Tasker comments, "Gastric juice that refluxes into the middle ear will cause transient damage to the Eustachian tube and the middle-ear mucosa before it can be neutralized, resulting in inflammation.
"This provides ideal conditions for secondary bacterial colonization, leading to the symptoms associated with glue ear.
"We therefore think that antireflux treatment could prevent otitis media with effusion."