Definition Sporotrichosis is a fungal infection that causes red, tender nodules on the fingers, wrists, and arms. The lymph nodes may also become infected.
What is going on in the body? A person may get sporotrichosis when exposed to soil, or when a thorn or splinter punctures the skin. The infection is caused by a fungus in the soil. Sometimes, breathing in the fungus can create an infection throughout the body.
What are the signs and symptoms of the disease? Sporotrichosis may begin with a sore or central blister that is red, tender, and appears under the skin of the fingers. A few days to a few weeks after exposure, the disease may progress:
The nodule becomes pink and ulcerates. Several days to a few weeks after the initial nodule appears, a chain of dark red nodules develops. Red streaks may move up the arm from the sores located on the wrist or arm.
A productive cough may develop if the organism is inhaled or reaches the lungs.
What are the causes and risks of the disease? Usually, infection from the fungus causing sporotrichosis comes about through a skin puncture with a contaminated thorn or sticker. Gardeners, farmers, and others working in brush, with rose bushes, barberry bushes, or certain types of moss are more at risk for this infection.
What can be done to prevent the disease? Prevention of sporotrichosis includes:
avoiding thorns or stickers while working in the garden
wearing gloves and protective clothing to reduce the risk of becoming infected
wearing a mask to protect the lungs from infection
How is the disease diagnosed? The first step in the diagnosis of sporotrichosis is a medical history and physical examination. The doctor may order a culture of pus from the sore to look for the fungus. Biopsy of the lesion is sometimes helpful. Other tests, including bone scan, bone marrow biopsy, blood tests, and x-rays may be used to rule out other conditions.
What are the long-term effects of the disease? Sporotrichosis can involve infection of various organs of the body. This condition can become life threatening if it spreads throughout the body.
What are the risks to others? Sporotrichosis is not contagious. It does not spread from one person to another.
What are the treatments for the disease? Sporotrichosis is usually treated with antifungal medications taken by mouth, such as a solution of potassium iodide or itraconazole. If the person has severe symptoms, is resistant to oral medications, or has infection elsewhere in the body, the doctor may give the amphotericin B through an intravenous line or IV. An IV is a thin tube inserted into the person's vein to provide fluids or medication. Covering the sores with loose-fitting bandages may help prevent secondary infection. If the bones, joints, or lungs have been infected with lesions, surgery may be necessary.
What are the side effects of the treatments? Side effects will depend on the medication used. Saturated solution of potassium iodide has the highest rate of side effects including nausea, vomiting, rash, and fever. Amphotericin B may cause fever, chills, and decreased kidney function. Surgery poses a risk of bleeding, infection, or allergic reaction to anaesthesia.
What happens after treatment for the disease? With prompt treatment, the sporotrichosis infection is usually completely cleared away. The infection, however, may come back.
How is the disease monitored? Any new or worsening symptoms should be reported to the doctor.
Author: Danielle Zerr, MD Reviewer: HealthAnswers Australia Medical Review Panel Editor: Dr David Taylor, Chief Medical Officer HealthAnswers Australia Last Updated: 1/10/2001 Contributors Potential conflict of interest information for reviewers available on request