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Dermatophytosis

Issue Description
Ringworm is the common name for the skin infection caused by a special group of fungi; it is not caused by a worm at all. The fungi feed upon the dead cells of skin and hair causing, in people, a classic round, red lesion with a ring of scale around the edges and normal recovering skin in the center. Because the ring of irritated, itchy skin looked like a worm, the infection was erroneously named. The fungi responsible are called "dermatophytes," meaning "plants that live on the skin" thus the more correct term for ringworm is dermatophytosis. The characteristic "ring" appearance is primarily a human phenomenon. In animals, ringworm requently looks like a dry, grey, scaly patch but can also mimic any other skin lesion and have any appearance.
Other Names
Ringworm


Symptoms
Dermatophytes are known to thrive deep in the hair follicles. When an infection develops, fungi can damage the hair shaft that result to falling out hair or breaking of skin. When the infection remains untreated, it can spread to other areas of the body that may lead to round or irregular shaped lesions that come in various sizes.

In dogs, canine ringworm is one of the most common skin disorders because it can be highly contagious. Studies show that canine ringworm can be acquired when a dog come to close contact with another dog that is infected with the fungal infection or when the dog stays in a place where the fungus thrive. Canine ringworm can also be transmitted when a dog get in touch with contaminated items such as collars, beddings, or blankets.

Canine ringworm symptoms may include circular patches of broken hair that is spreading rapidly, existence of evident skin lesions, crusty, scurfy, or scaly skin, and itchy and painful hairless skin patches. Once one or two of these symptoms, dogs should be brought to a veterinarian for proper diagnosis.


Treatment
Commitment is the key to success especially if you have more than one pet. Infected animals are constantly shedding spores into the environment (your house) thus disinfection is just as important as treatment of the affected pet. There are primarily two medications being used to treat ringworm: Griseofulvin and Itraconazole (brand name "Sporonox"). Veterinary dermatologists disagree as to which is better. Both medications are relatively expensive, must be given with food, and have significant potential to cause birth defects in pregnant pets.

Treatment with either medication typically is continued for 1-2 months and should not be discontinued until the pet cultures negative. Stopping when the pet simply looks well visually frequently leads to recurrence of the disease.

Griseofulvin (brand name Fulvicin)

This medication must be given with a fatty meal in order for an effective dose to be absorbed by the pet. Persian cats and young kittens are felt to be sensitive to its side effects which usually are limited to nausea but can include liver disease and serious white blood cell changes. Cats infected with the Feline Immunodeficiency Virus commonly develop life-threatening blood cell changes and should never be exposed to this medication. Despite the side effects, which can be severe for some individuals, Griseofulvin is still the traditional medication for the treatment of ringworm and is usually somewhat less expensive than Itraconazole.


Itraconazole
This medication is highly effective in the treatment of ringworm but is available in capsules far too large to be useful to most small animals. This means that a special company must reformulated the medication into a more useful size. Nausea is a potential side effect for this medication but probably the main reason it is passed by in favor of griseofulvin is expense. Itraconazole is also effective in treating many life-threatening fungal infections whereas Griseofulvin only treats ringworm.

By increasing the amount of Itraconazole in the environment, we may be creating resistance in more dangerous fungi which could become a problem over the years.

There have been several studies which showed that this fungal infection should eventually resolve on its own. Typically, this takes four months, a long time in a home environment for contamination to be occurring continuously. We recommend treatment for this infection rather than waiting for it to go away.


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