Mastoiditis, which is an infection of the bone positioned behind the ear, most commonly affects children and usually develops because of bacteria. While it isn't rare in adults, the incidence of mastoiditis in adults isn't common either. The infection can affect people of any age and cause such symptoms as fever, swelling of the ear, especially the lobe, redness, pain and fatigue. A person with this condition may also have fluid that drains from his ear and feel abnormally irritable.
Children are far more likely to develop mastoiditis than adults, but this doesn't mean adults are immune to it. There are cases of mastoiditis in adults, but they are infrequent. When an adult does develop mastoiditis, this means a bone behind his ear, which is referred to as the mastoid bone, has become infected. Usually, this occurs as a result of bacteria — Haemophilus influenzae and Streptococcus pneumoniae are among those that are most often at fault. An adult can have an acute case of mastoiditis, which means the infection develops suddenly and lasts for only a short time, or he may develop a chronic case, which usually means symptoms develop gradually, but the condition lingers on, often for weeks or months.
Although cases of mastoiditis in adults are less common than in children, it may prove more common in adults who are prone to ear infections. This is because mastoiditis doesn't usually develop on its own, but instead follows an infection of the inner ear. Often, this happens when an adult has an inner ear infection and fails to seek treatment in a timely manner. In such a case, bacteria from the ear infection can move into the cells of the mastoid bone and cause infection there. Sometimes, this issue may be compounded by a cyst that prevents the ear from draining and encourages the development of a mastoid infection.
The reason a doctor is less likely to diagnose frequent cases of mastoiditis in adults as compared to children may involve the likelihood of children to develop ear infections. In general, children are far more likely to develop infections of the middle ear as well as experience reoccurring ear infections. This may be due, at least in part, to the fact that the ears of young children do not drain as easily or effectively as those of adults. Children's immune systems may also prove weaker and less stable, which can also contribute to these differences.