Sporotrichosis
Sporotrichosis is caused by fungus called Sporothrix schenckii commonly found in soil and on plants. The skin infection that gains access through a break in the skin. Other routes of infection are by ingestion or inhalation of spores. The disease is most common among male cats that prowl in thorny underbrush or sharp prairie grass. Most cases are reported in the northern and central portions of the United States.
Siamese cats seem to be more predisposed to develop the infection than most other breeds. Entire male cats under 4 years of age often get infected during fights with other males.
There are two forms of the infection. Plaque sporotrichosis — occurs if the infection is localized at the site of puncture. Disseminated sporotrichosis&mdash occurs when the infection is spread to lymph nodes, joints, eyes, and meninges. Individuals with chronic diseases such as diabetes mellitus, HIV, or cats who are given glucocorticoids are especially predisposed to develop disseminated form of sporotrichosis.
Signs of Sporotrichosis
A nodule forms at the site of a skin wound, usually on the feet and legs, face or base of tail. The hair over the nodule falls out, leaving a most ulcerated surface. In some cases there is a little surface reaction, but you may see several small firm nodules beneath the skin that appear to form a chain. Skin necrosis may occur to reveal the underlying muscle. Normal grooming may spread the infection to other parts of the body.
On rare occasions the disease spreads internally to the liver and lungs. In these individuals the outlook for cure is guarded. The diagnosis is made by removing a piece of tissue and examining it under the microscope; or growing the fungus in culture.
Treatment of Sporotrichosis
The reponse to treatment is excellent when disease is limited to the skin and surrounding tissues. Potassium iodide is the agent of choice. ketoconazole and Itraconazole also have been used. Amphotericin B is used for internal infection. These drugs have toxic potential and require close veterinary supervision.
CAUTION: Sporotrichosis has been known to infect humans handling cats with infective drainage from nodules and ulcers. Wear rubber gloves and use strict hygienic precautions when handling cats with draining wounds.
The first symptom is usually a small painless bump that’s red, pink, or
purple. This is followed by one or more additional bumps/nodules which open and
may resemble boils. Eventually lesions look like open sores, or ulcerations, and
heal slowly.
Most cases of sporotrichosis occur in people who work with plants or contact infected cats. Some outbreaks have been linked to contaminated sphagnum moss,
hay, or wood. Disseminated sporotrichosis is a serious, potentially life-threatening disease with a grave prognosis. Disseminated sporotrichosis appears to be more common in people with underlying conditions such as alcoholism, diabetes, cancer, or suppressed immune system. 1
References
- Sporotrichosis. Rose Handler's Disease
Thursday, February 09, 2012
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