Ear infections in adults may involve the inner, middle or external ear. The causes of ear infections prove similar in adults and children. Viruses, bacteria and, less commonly, fungi can cause ear infections in adults. Viral ear infections typically resolve spontaneously. Bacterial and fungal ear infections may require topical or oral prescription therapy.
Ear Canal Trauma
Earwax coats the external ear canal, inhibiting the overgrowth of bacteria and protecting the delicate skin within the ear. Infection of the ear canal, known as otitis externa, may arise with skin trauma caused by the removal of earwax with cotton swabs, hairpins or other makeshift ear-cleaning implements, report Drs. J. David Osguthorpe and David Nielsen in a November 2006 article published in "American Family Physician." Removal of the antibacterial earwax often causes small scratches in the ear canal skin, potentially leading to infection. Common signs and symptoms of otitis externa include ear canal itching, pain, redness and discharge.
Ear Canal Moisture
Excessive moisture in the ear canal may lead to bacterial overgrowth and otitis externa, reports the American Academy of Otolaryngology -- Head and Neck Surgery. Although otitis externa, also known as swimmer's ear, occurs most commonly in children and teenagers, the condition also affects adults. Swimming, scuba diving, snorkeling, showering and other activities that expose the external ear canal to water may predispose to the development of otitis externa. Earplugs may help keep water out of the ear canal. Cotton swabs should not be inserted into the ear canal, states the Academy.
Upper Respiratory Infection
An upper respiratory infection, such as a cold, sore throat or sinusitis, may lead to a middle ear infection in adults, reports the medical information website eMedTV. Viruses or bacteria in the nasal cavity may enter the eustachian tube, the pressure-equalizing structure between the back of the nose and the middle ear. Germs may migrate through the eustachian tube, causing a middle ear infection, or otitis media.
The risk for otitis media associated with an upper respiratory infection proves significantly lower for adults compared to infants and young children. In adults, the eustachian tube angles downward from the middle ear. This helps keep germs in the nose and throat from ascending into the middle ear. In infants and young children, the eustachian tube is virtually horizontal, which increases the likelihood of nasal contaminants reaching the middle ear.
Contamination of the Inner Ear
Infections of the inner ear, known as vestibular neuritis and labyrinthitis, most commonly arise due to viral contamination of the inner ear structures. These infections occur primarily in adults, reports Dr. Timothy Hain of Northwestern University Medical School in an online article published by the American Hearing Research Foundation. Uncommonly, bacteria in the middle ear may spread to the inner ear, causing infection, notes Hain. Symptoms of an inner ear infection typically include dizziness, nausea, vomiting, hearing impairment and phantom noise, such as buzzing or ringing. Inner ear infections typically do not cause pain.
References
- "American Family Physician"; Otitis Externa: Review and Clinical Update; J. David Osguthorpe, M.D., David R. Nielsen, M.D.; November 2006
- American Academy of Otolaryngology --- Head and Neck Surgery: Swimmer's Ear
- eMedTV: Adult Ear Infections
- American Hearing Research Foundation: Vestibular Neuritis and Labyrinthitis
