Sporotrichosis is a fungal disease that can affect both animals and people. It is usually acquired from the environment through a cut or scrape in the skin but can be acquired from contact with animals as well. Infection with sporotrichosis in cats can range from no signs of illness to very serious disease. Signs often begin with small draining wounds that become raised lumps with the surface eroded away. The disease can worsen.
Three forms of sporotrichosis can infect people.
- The first form is the cutaneous or skin form, which can progress from small raised areas on the skin to infection invading the lymph nodes and forming nodules that eventually ulcerate.
- The second is the disseminated form, which occurs when the infection affects the internal organs and bones.
- In the third form, the pulmonary form, a person acquires the infection through inhalation the fungus into the lungs, which often leads to chronic disease similar to tuberculosis.
The latter two forms are potentially fatal.
The symptoms of sporotrichosis depend on where the fungus is growing. Contact your healthcare provider if you have symptoms that you think are related to sporotrichosis.
Sporotrichosis usually affects the skin or tissues underneath the skin. The first symptom of cutaneous (skin) sporotrichosis is usually a small, painless bump that can develop any time from 1 to 12 weeks after exposure to the fungus. The bump can be red, pink, or purple, and it usually appears on the finger, hand, or arm where the fungus has entered through a break in the skin. The bump will eventually grow larger and may look like an open sore or ulcer that is very slow to heal. Additional bumps or sores may appear later near the original one.
Pulmonary (lung) sporotrichosis is less common than the cutaneous (skin) form of the infection. Symptoms include cough, shorthess of breath, chest pain, and fever.
Symptoms of disseminated sporotrichosis depend on the body part affected. For example, infection of the joints can cause joint pain that may be confused with rheumatoid arthritis. Infections of the central nervous system can involve difficulty thinking, headache, and seizures.
Who gets sporotrichosis?
Overall, sporotrichosis is rare, but people who handle plant matter such as sphagnum moss, rose bushes, or hay are more likely to get the infection. For example, sporotrichosis outbreaks have occurred among forestry workers, people who worked in tree nurseries and garden centers, and people who handled hay bales.
The severe forms of sporotrichosis (those that affect the lungs, bones or joints, or central nervous system) usually affect people with weakened immune systems or underlying diseases including diabetes, chronic obstructive pulmonary disease (COPD), alcoholism, or HIV infection.1,3,4
How can I lower the chance of developing sporotrichosis?
You can lower the chance of getting sporotrichosis by wearing protective clothing such as gloves and long sleeves when handling plant matter that can cause minor cuts or scrapes.
How is sporotrichosis treated?
Most cases of sporotrichosis only involve the skin or the tissues underneath the skin. These infections are not life-threatening but must be treated with prescription antifungal medication for several months. The most common treatment for this type of sporotrichosis is itraconazole, taken by mouth for 3 to 6 months. Supersaturated potassium iodide (SSKI) is another treatment option for cutaneous (skin) sporotrichosis. However, SSKI and azole drugs like itraconazole should not be used during pregnancy.
Patients with severe forms of sporotrichosis are usually treated with amphotericin B, which is given through a vein. Itraconazole is often used after the initial treatment with amphotericin B, for a total of at least 1 year of antifungal treatment. People with sporotrichosis in the lungs may also need surgery to cut away the infected tissue.