otitis externa otitis externa otitis externa, also called swimmer's ear, is inflammation of the ear canal. it often presents with ear pain, swelling of the ear canal, and occasionally decreased hearing. typically there is pain with movement of the outer ear. a high fever is typically not present except in severe cases. not to be confused with surfer's ear. otitis externaother namesexternal otitis, swimmer's eara moderate case of otitis externa. there is narrowing of the ear channel, with a small amount of exudate and swelling of the outer ear.specialtyotorhinolaryngologysymptomsear pain, swelling of the ear canal, decreased hearing, difficulty chewingtypesacute, chroniccausesbacterial infection, allergies, autoimmune disordersrisk factorsswimming, minor trauma from cleaning, using hearing aids or ear plugs, diabetes, psoriasis, dermatitisdiagnostic methodbased on symptoms, microbial culturedifferential diagnosisperichondritispreventionacetic acid ear dropstreatmentantibiotic drops such as ofloxacin, acetic acidfrequency~2% of people a year otitis externa may be acute (lasting less than six weeks) or chronic (lasting more than three months). acute cases are typically due to bacterial infection, and chronic cases are often due to allergies and autoimmune disorders. the most common cause of otitis externa is bacterial. risk factors for acute cases include swimming, minor trauma from cleaning, using hearing aids and ear plugs, and other skin problems, such as psoriasis and dermatitis. people with diabetes are at risk of a severe form of malignant otitis externa. diagnosis is based on the signs and symptoms. culturing the ear canal may be useful in chronic or severe cases. acetic acid ear drops may be used as a preventive measure. treatment of acute cases is typically with antibiotic drops, such as ofloxacin or acetic acid. steroid drops may be used in addition to antibiotics. pain medications such as ibuprofen may be used for the pain. antibiotics by mouth are not recommended unless the person has poor immune function or there is infection of the skin around the ear. typically, improvement occurs within a day of the start of treatment. treatment of chronic cases depends on the cause. otitis externa affects 1–3% of people a year; more than 95% of cases are acute. about 10% of people are affected at some point in their lives. it occurs most commonly among children between the ages of seven and twelve and among the elderly. it occurs with near equal frequency in males and females. those who live in warm and wet climates are more often affected. signs and symptoms a mild case of otitis externa. a severe case of acute otitis externa. note the narrowing of the ear channel, the large amounts of exudate, and swelling of the outer ear. tenderness of pinna is the predominant complaint and the only symptom directly related to the severity of acute external otitis. unlike other forms of ear infections, we observe tenderness in outer ear i.e., the pain of acute external otitis is worsened when the outer ear is touched or pulled gently. pushing the tragus, the tablike portion of the auricle that projects out just in front of the ear canal opening, also typically causes pain in this condition as to be diagnostic of external otitis on physical examination. people may also experience ear discharge and itchiness. when enough swelling and discharge in the ear canal is present to block the opening, external otitis may cause temporary conductive hearing loss. because the symptoms of external otitis lead many people to attempt to clean out the ear canal (or scratch it) with slim implements, self-cleaning attempts generally lead to additional traumas of the injured skin, so rapid worsening of the condition often occurs. causes the two factors that are required for external otitis to develop are (1) the presence of germs that can infect the skin and (2) impairments in the integrity of the skin of the ear canal that allow an infection to occur. if the skin is healthy and uninjured, only exposure to a high concentration of pathogens, such as submersion in a pond contaminated by sewage, is likely to set off an episode. however, if there are chronic skin conditions that affect the ear canal skin, such as atopic dermatitis, seborrheic dermatitis, psoriasis or abnormalities of keratin production, or if there has been a break in the skin from trauma, even the normal bacteria found in the ear canal may cause infection and full-blown symptoms of external otitis. fungal ear canal infections, also known as otomycosis, range from inconsequential to extremely severe. fungi can be saprophytic, in which there are no symptoms and the fungus simply co-exists in the ear canal in a harmless parasitic relationship with the host, in which case the only physical finding is the presence of a fungus. if the fungus begins active reproduction, the ear canal can fill with dense fungal debris, causing pressure and ever-increasing pain that is unrelenting until the fungus is removed from the canal and anti-fungal medication is used. most antibacterial ear drops also contain a steroid to hasten resolution of canal edema and pain. unfortunately, such drops make the fungal infection worse. prolonged use of them promotes the growth of fungus in the ear canal. antibacterial ear drops should be used for a maximum of one week, but 5 days is usually enough. otomycosis responds more than 95% of the time to a three-day course of the same over-the-counter anti-fungal solutions used for athlete's foot. swimming swimming in polluted water is a common way to contract swimmer's ear, but it is also possible to contract swimmer's ear from water trapped in the ear canal after a shower, especially in a humid climate. prolonged swimming can saturate the skin of the canal, compromising its barrier function and making it more susceptible to further damage if the ear is instrumented with cotton swabs after swimming. constriction of the ear canal from bone growth (surfer's ear) can trap debris leading to infection. saturation divers have reported otitis externa during occupational exposure. objects in ear even without exposure to water, the use of objects such as cotton swabs or other small objects to clear the ear canal is enough to cause breaks in the skin, and allow the condition to develop. once the skin of the ear canal is inflamed, external otitis can be drastically enhanced by either scratching the ear canal with an object or by allowing water to remain in the ear canal for any prolonged length of time. infections the majority of cases are due to pseudomonas aeruginosa and staphylococcus aureus, followed by a great number of other gram-positive and gram-negative species. candida albicans and aspergillus species are the most common fungal pathogens responsible for the condition. diagnosis when the ear is inspected, the canal appears red and swollen in well-developed cases. the ear canal may also appear eczema-like, with scaly shedding of skin. touching or moving the outer ear increases the pain, and this maneuver on physical exam is important in establishing the clinical diagnosis. it may be difficult to see the eardrum with an otoscope at the initial examination because of narrowing of the ear canal from inflammation and the presence of drainage and debris. sometimes the diagnosis of external otitis is presumptive and return visits are required to fully examine the ear. the culture of the drainage may identify the bacteria or fungus causing infection, but is not part of the routine diagnostic evaluation. in severe cases of external otitis, there may be swelling of the lymph node(s) directly beneath the ear. the diagnosis may be missed in most early cases because the examination of the ear, with the exception of pain with manipulation, is nearly normal. in some early cases, the most striking visual finding is the lack of earwax. as a moderate or severe case of external otitis resolves, weeks may be required before the ear canal again shows a normal amount of it. classification in contrast to the chronic otitis externa, acute otitis externa (aoe) is predominantly a bacterial infection, occurs suddenly, rapidly worsens, and becomes painful. the ear canal has an abundant nerve supply, so the pain is often severe enough to interfere with sleep. wax in the ear can combine with the swelling of the canal skin and the associated pus to block the canal and dampen hearing, creating a temporary conductive hearing loss. in more severe or untreated cases, the infection can spread to the soft tissues of the face that surround the adjacent parotid gland and the jaw joint, making chewing painful. in its mildest forms, otitis externa is so common that some ear nose and throat physicians have suggested that most people will have at least a brief episode at some point in life. the skin of the bony ear canal is unique, in that it is not movable but is closely attached to the bone, and it is almost paper-thin. for these reasons, it is easily abraded or torn by even minimal physical force. inflammation of the ear canal skin typically begins with a physical insult, most often from injury caused by attempts at self-cleaning or scratching with cotton swabs, pen caps, fingernails, hair pins, keys, or other small implements. another causative factor for acute infection is prolonged water exposure in the forms of swimming or exposure to extreme humidity, which can compromise the protective barrier function of the canal skin, allowing bacteria to flourish, hence the name "swimmer's ear". prevention the strategies for preventing acute external otitis are similar to those for treatment. avoid inserting anything into the ear canal: use of cotton buds or swabs is the most common event leading to acute otitis externa. most normal ear canals have a self-cleaning and self-drying mechanism, the latter by simple evaporation. after prolonged swimming, a person prone to external otitis can dry the ears using a small battery-powered ear dryer, available at many retailers, especially shops catering to watersports enthusiasts. alternatively, drops containing dilute acetic acid (vinegar diluted 3:1) or burow's solution may be used. it is especially important not to instrument ears when the skin is saturated with water, as it is very susceptible to injury, which can lead to external otitis. avoid swimming in polluted water. avoid washing hair or swimming if very mild symptoms of acute external otitis begin. although the use of earplugs, when swimming and shampooing hair, may help prevent external otitis, there are important details in the use of plugs. hard and poorly fitting earplugs can scratch the ear canal skin and set off an episode. when earplugs are used during an acute episode, either disposable plugs are recommended, or used plugs must be cleaned and dried properly to avoid contaminating the healing ear canal with infected discharge. according to one source, the use of in-ear headphones during otherwise "dry" exercise in the summer has been associated with the development of swimmer's ear since the plugs can create a warm and moist environment inside the ears. the source claims that on-ear or over-ear headphones can be a better alternative for preventing swimmer's ear. treatment medications effective solutions for the ear canal include acidifying and drying agents, used either singly or in combination. when the ear canal skin is inflamed from the acute otitis externa, the use of dilute acetic acid may be painful. burow's solution is a very effective remedy against both bacterial and fungal external otitis. this is a buffered mixture of aluminium sulfate and acetic acid, and is available without prescription in the united states. ear drops are the mainstay of treatment for external otitis. some contain antibiotics, either antibacterial or antifungal, and others are simply designed to mildly acidify the ear canal environment to discourage bacterial growth. some prescription drops also contain anti-inflammatory steroids, which help to resolve swelling and itching. although there is evidence that steroids are effective at reducing the length of treatment time required, fungal otitis externa (also called otomycosis) may be caused or aggravated by overly prolonged use of steroid-containing drops. antibiotics by mouth should not be used to treat uncomplicated acute otitis externa. antibiotics by mouth are not a sufficient response to bacteria which cause this condition and have significant side effects including increased risk of opportunistic infection. in contrast, topical products can treat this condition. oral anti-pseudomonal antibiotics can be used in case of severe soft tissue swelling extending into the face and neck and may hasten recovery. although the acute