Otitis externa in animals
Encyclopedia
Otitis externa
is an inflammation
of the outer ear
and ear canal. Animals are commonly prone to ear infection, and this is one of the most common manifestations of allergy in dogs. In dogs, those breeds with floppy ears are more prone, since air flow is limited and a warm, moist environment built up, which is conducive to infection. The external ear in animals is longer and deeper than in humans, which makes it easier for infection or wax to build up or be hard to remove. Complete ear canal inspection requires the use of an otoscope
by a veterinarian
.
Infections are usually secondary to inflammation or to improper grooming techniques. Infections can be caused by both bacteria
l and fungal
origin, as well as small organisms such as ear mite
s. Malassezia pachydermatis is a common fungal agent for ear infections in dogs. Staphylococcus intermedius is the most common bacterial infection. A more serious ear infection, with pus in the ear, may be caused by Pseudomonas aeruginosa
.
The aim of cleaning is to remove any byproducts of the infection which lead to further irritation and discomfort, and may be in turn, causes of further infection. Good care often involves cleaning the ear daily, to prevent build-up and bring the infection under control.
Ear medications are applied after cleaning and drying, and is usually in the form of ear drops or ointment applied daily or twice daily for one or two weeks. The type of infection must be identified by the veterinarian by examining a sample of ear exudate
under a microscope
, since bacterial infection will only respond to antibiotic
s, fungal infection to a fungicide
, and ear mites to an insecticide
.
may be indicated. Treatment for ear mites include ear drops that contain pyrethrins or an avermectin such as ivermectin or selamectin.
Cleaning of the ears is very important for treatment of ear infections. Cleansing and antiseptic
mixtures are made from isopropyl (rubbing) alcohol
, boric acid
and acetic acid
(vinegar
) in various proportions. In some recipes, povidone-iodine
(betadine
) is added as well.
Otitis externa
Otitis externa is an inflammation of the outer ear and ear canal. Along with otitis media, external otitis is one of the two human conditions commonly called "earache". It also occurs in many other species. Inflammation of the skin of the ear canal is the essence of this disorder...
is an inflammation
Inflammation
Inflammation is part of the complex biological response of vascular tissues to harmful stimuli, such as pathogens, damaged cells, or irritants. Inflammation is a protective attempt by the organism to remove the injurious stimuli and to initiate the healing process...
of the outer ear
Ear
The ear is the organ that detects sound. It not only receives sound, but also aids in balance and body position. The ear is part of the auditory system....
and ear canal. Animals are commonly prone to ear infection, and this is one of the most common manifestations of allergy in dogs. In dogs, those breeds with floppy ears are more prone, since air flow is limited and a warm, moist environment built up, which is conducive to infection. The external ear in animals is longer and deeper than in humans, which makes it easier for infection or wax to build up or be hard to remove. Complete ear canal inspection requires the use of an otoscope
Otoscope
thumb|right|200px|Otoscope - Image of an otoscope thumb|200px|Anatomy of the human ear.thumb|200px|Right tympanic membrane as seen through a speculum.An Otoscope or auriscope is a medical device which is used to look into the ears...
by a veterinarian
Veterinarian
A veterinary physician, colloquially called a vet, shortened from veterinarian or veterinary surgeon , is a professional who treats disease, disorder and injury in animals....
.
Infections are usually secondary to inflammation or to improper grooming techniques. Infections can be caused by both bacteria
Bacteria
Bacteria are a large domain of prokaryotic microorganisms. Typically a few micrometres in length, bacteria have a wide range of shapes, ranging from spheres to rods and spirals...
l and fungal
Mycosis
A mycosis is a fungal infection of animals, including humans. Mycoses are common, and a variety of environmental and physiological conditions can contribute to the development of fungal diseases...
origin, as well as small organisms such as ear mite
Ear mite
Ear mites are mites that live in the ears of animals. The most commonly seen species is Otodectes cynotis .-Contagion:...
s. Malassezia pachydermatis is a common fungal agent for ear infections in dogs. Staphylococcus intermedius is the most common bacterial infection. A more serious ear infection, with pus in the ear, may be caused by Pseudomonas aeruginosa
Pseudomonas aeruginosa
Pseudomonas aeruginosa is a common bacterium that can cause disease in animals, including humans. It is found in soil, water, skin flora, and most man-made environments throughout the world. It thrives not only in normal atmospheres, but also in hypoxic atmospheres, and has, thus, colonized many...
.
Symptoms
Signs of ear infection include shaking of the head, and scratching at or under the ear. Some animals may also paw the ear or try to rub it on other objects to relieve pain and discomfort. Ear infections often result in a darker red ear, dirt in the ear, or a general inflamed appearance.Treatment
Treatment is usually by a dual regimen of ear cleaning and ear medication. Ear cleaning should be demonstrated by a veterinarian, due to the risk of pushing infected material deeper into the ear.The aim of cleaning is to remove any byproducts of the infection which lead to further irritation and discomfort, and may be in turn, causes of further infection. Good care often involves cleaning the ear daily, to prevent build-up and bring the infection under control.
Ear medications are applied after cleaning and drying, and is usually in the form of ear drops or ointment applied daily or twice daily for one or two weeks. The type of infection must be identified by the veterinarian by examining a sample of ear exudate
Exudate
An exudate is any fluid that filters from the circulatory system into lesions or areas of inflammation. It can apply to plants as well as animals. Its composition varies but generally includes water and the dissolved solutes of the main circulatory fluid such as sap or blood...
under a microscope
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...
, since bacterial infection will only respond to antibiotic
Antibiotic
An antibacterial is a compound or substance that kills or slows down the growth of bacteria.The term is often used synonymously with the term antibiotic; today, however, with increased knowledge of the causative agents of various infectious diseases, antibiotic has come to denote a broader range of...
s, fungal infection to a fungicide
Fungicide
Fungicides are chemical compounds or biological organisms used to kill or inhibit fungi or fungal spores. Fungi can cause serious damage in agriculture, resulting in critical losses of yield, quality and profit. Fungicides are used both in agriculture and to fight fungal infections in animals...
, and ear mites to an insecticide
Insecticide
An insecticide is a pesticide used against insects. They include ovicides and larvicides used against the eggs and larvae of insects respectively. Insecticides are used in agriculture, medicine, industry and the household. The use of insecticides is believed to be one of the major factors behind...
.
Specifics of treatment
In mild cases, a product with anti-inflammatory, anti-fungal and anti-bacterial ingredients are often employed. In more severe cases, ear cleaning under sedation or anesthesia may be required and evaluation for otitis mediaOtitis media
Otitis media is inflammation of the middle ear, or a middle ear infection.It occurs in the area between the tympanic membrane and the inner ear, including a duct known as the eustachian tube. It is one of the two categories of ear inflammation that can underlie what is commonly called an earache,...
may be indicated. Treatment for ear mites include ear drops that contain pyrethrins or an avermectin such as ivermectin or selamectin.
Cleaning of the ears is very important for treatment of ear infections. Cleansing and antiseptic
Antiseptic
Antiseptics are antimicrobial substances that are applied to living tissue/skin to reduce the possibility of infection, sepsis, or putrefaction...
mixtures are made from isopropyl (rubbing) alcohol
Isopropyl alcohol
Isopropyl alcohol is a common name for a chemical compound with the molecular formula C3H8O. It is a colorless, flammable chemical compound with a strong odor...
, boric acid
Boric acid
Boric acid, also called hydrogen borate or boracic acid or orthoboric acid or acidum boricum, is a weak acid of boron often used as an antiseptic, insecticide, flame retardant, as a neutron absorber, and as a precursor of other chemical compounds. It exists in the form of colorless crystals or a...
and acetic acid
Acetic acid
Acetic acid is an organic compound with the chemical formula CH3CO2H . It is a colourless liquid that when undiluted is also called glacial acetic acid. Acetic acid is the main component of vinegar , and has a distinctive sour taste and pungent smell...
(vinegar
Vinegar
Vinegar is a liquid substance consisting mainly of acetic acid and water, the acetic acid being produced through the fermentation of ethanol by acetic acid bacteria. Commercial vinegar is produced either by fast or slow fermentation processes. Slow methods generally are used with traditional...
) in various proportions. In some recipes, povidone-iodine
Iodine
Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....
(betadine
Betadine
Povidone-iodine is a stable chemical complex of polyvinylpyrrolidone and elemental iodine. It contains from 9.0% to 12.0% available iodine, calculated on a dry basis....
) is added as well.