External otitis

from Wikipedia, the free encyclopedia
Inflammation of the ear canal with eczema
Classification according to ICD-10
H60 External otitis
ICD-10 online (WHO version 2019)

The otitis externa ( Latin ) or German outer ear inflammation (in animals also called "Ohrenzwang") is an inflammation of the outer ear , especially the external auditory canal , in a broader sense also the auricle. In small animal medicine , it is considered the most common disease. In humans, the term is primarily used for inflammation of the cutis and subcutis of the external auditory canal, which may also affect the eardrum and auricle.

causes

Causes of otitis externa are softening ( maceration ) of the skin of the ear canal due to fluids, minor injuries (e.g. from cotton swabs) or foreign bodies with subsequent local bacterial infection . The most common bacterial pathogens causing otitis externa in humans are Pseudomonas aeruginosa and staphylococci . The pseudomonads occur in warm water and are also chlorine-tolerant, so otitis externa diffusa is a common disease during bathing holidays and is therefore also called "bathing otitis" or "swimming pool otitis". It is carried surfer's ear ( "surfers ear" ( Surfer's ear ), "swimmers ear" ( swimmer's ear ) or "divers ear" ( diver's ear favors)).

External otitis can also be a manifestation of a general skin disease that is particularly pronounced on the very sensitive skin of the ear canal. Allergies and autoimmune diseases can also be triggers here.

In animals, yeasts (e.g. Malassezia ) and mites ( ear mange ) are often the trigger for otitis externa. The possible causes in dogs and cats are: Ectoparasites , foreign bodies, hypersensitivity (hypersensitivity), dermatophytes , keratinization disorders and endocrinopathies , metabolic causes, immune diseases, traumatic causes . In the case of foreign bodies, foreign bodies from the ear itself play a more important role than foreign bodies that have penetrated from the outside, which occur due to disturbances in the self-cleaning mechanism of the ear. These are not infrequently caused by improper treatment.

A severe case of external otitis. You can see a clear narrowing of the external ear canal and copious purulent discharge.

Symptoms

The main symptoms are severe pain and itching. Fever, dizziness and nausea can also occur. Pressure on the tragus and tension on the auricle ("external points") are particularly painful . Depending on the severity and pathogen, the skin is reddened and swollen or other efflorescences such as pustules , papules , ulcers or crusts appear. Lymph node swelling can also occur. In the more or less swollen ear canal, there is flaked material ( detritus ), not infrequently the ear canal becomes wet or there is even purulent secretion. Hearing can also be reduced because of the swollen ear canal. Sleeping on your side is hardly or not at all possible depending on the severity of the inflammation.

Forms and differential diagnosis

One differentiates:

  • acute otitis externa diffusa (AOE)
  • the otitis externa circumscripta
  • chronic otitis externa (COE) and
  • otitis externa maligna (necroticans) (OEM)

The acute otitis externa diffusa develops rapidly and is usually very painful because the periosteum is stimulated in the area of the ear canal. It is a phlegmon of the ear canal. There are clear signs of inflammation such as reddening of the ear canal skin and narrowing of the ear canal due to swelling. If left untreated, there is a risk of further development to otitis externa maligna. In otitis externa circumscripta , only parts of the auditory canal are inflamed, comparable to an auditory canal furuncle . The symptoms are correspondingly lower. A chronic otitis externa occurs when an acute inflammation does not heal properly or primarily a little virulent pathogen that caused the inflammation. A eczema of the auditory canal, by colonization of bacteria pass into a chronic otitis externa. The malignant external otitis (necrotizing) is the most dangerous form of the disease. It usually arises from acute otitis externa with a very virulent pathogen or when the patient's immune system is weak. The addition of necroticans means that the severe bacterial inflammation has led to tissue loss in the area of ​​the ear canal.

The following diseases do not fall under the term otitis externa and must be differentiated from a differential diagnosis:

Perichondritis is primarily an inflammation of the cartilage of the auricle or the outer part of the ear canal. Erysipelas is usually triggered by an acute infection of the skin by β-hemolytic group A streptococci and, if left untreated, spreads rapidly to the scalp. Otomycosis is a fungal infection of the skin of the ear canal and / or the auricle. Zoster oticus is a form of shingles that affects cranial nerves. The otitis externa bullosa sive haemorrhagica belongs to the autoimmune blistering dermatoses, i.e. skin diseases in which blisters develop as a result of an autoimmune reaction. Primarily these skin blisters are not infected, but can be colonized after they burst. Otitis media (otitis media) spreads to the ear canal after perforation. Because the origin is the middle ear, the term otitis externa is not used. The ear canal eczema is a chronic inflammatory, itchy skin disorder of the ear canal, often as part of Eczema other body parts. The cholesteatoma is also known as a pearly tumor and develops in the middle ear as a result of the ingrowth of squamous epithelium in the ear canal after perforation of the eardrum. The cholesteatoma can become so large that it expands through the eardrum perforation into the ear canal. Surgical removal is indicated in all cases. The skin of the ear canal, like the rest of the skin of the body, can become malignant and develop into ear canal cancer. Most often it is squamous cell carcinoma, which is difficult to treat without loss of function if it is larger.

treatment

Ear infection in a dog
Neck ruff prevents the ear from scratching

Treatment is based on the cause and takes into account predisposing and sustaining factors. Thorough cleaning or rinsing of the ear canal is essential, any foreign bodies must be removed ("Thorough cleaning is half the therapy"). Insertion of a narrow strip of gauze soaked in concentrated alcohol or special ear drops. The ear drops usually contain antibiotics and anti-inflammatory agents, not infrequently alcohol to disinfect and dry out. However, they may only be administered if the eardrum is intact. Systemic administration of a suitable antibiotic is only necessary in particularly severe cases . An incision can also be useful for an ear canal furuncle . Warmth is not recommended, it often increases the pain. Acaricides are used for mites, and this drug is mostly applied locally ( topically ). In the case of allergic or immune-related otitis, anti-inflammatory agents ( glucocorticoids ) are used.

Complications

Possible dangers in otitis externa are the spread of infection into the surrounding soft tissue , spreading to the eardrum (myringitis) and, in extreme cases, bone marrow inflammation of the skull base with multiple cranial nerve failures .

literature

Individual evidence

  1. ↑ a b c Wolfgang Osthold, Regina Wagner: Otitis externa in dogs and cats. In: Small Animal Medicine. No. 9/10, 2009, pp. 262–275 ( pdf ( memento of October 23, 2013 in the Internet Archive ))
  2. ^ A b c Susanne Wiegand, Reinhard Berner, Antonius Schneider, Ellen Lundershausen, Andreas Dietz: Otitis externa — investigation and evidence-based treatment . In: Deutsches Aerzteblatt Online . March 29, 2019, ISSN  1866-0452 , doi : 10.3238 / arztebl.2019.0224 , PMID 31064650 , PMC 6522672 (free full text) - ( aerzteblatt.de [accessed on July 21, 2019]).
  3. ↑ Inflammation of the ear: infection of the outer ear (otitis externa). In: unbeschwert-hoeren.de. Retrieved November 4, 2019 .