Sporotrichosis is a fungal infection that frequently occurs following a minor injury while gardening or farming. Spores, which live in vegetation, enter the skin and begin to grow. The fungus follows the lymph channels up the extremity. Granulomatous lesions develop along the lymph channel, ulcerate, and drain. If left untreated, this condition can persist for years.
What is sporotrichosis?
Sporotrichosis is a fungal infection caused by a fungus called Sporothrix schenckii. It usually infects the skin.
Who gets sporotrichosis?
Persons handling thorny plants, sphagnum moss, or baled hay are at increased risk of getting sporotrichosis. Outbreaks have occurred among nursery workers handling sphagnum moss, rose gardeners, children playing on baled hay, and greenhouse workers handling bayberry thorns contaminated by the fungus. A number of cases have occurred among nursery workers, especially workers handling sphagnum moss topiaries.
How is the fungus spread?
The fungus can be found in sphagnum moss, in hay, in other plant materials, and in the soil. It enters the skin through small cuts or punctures from thorns, barbs, pine needles, or wires. It can also be inhaled and cause pulmonary infection or disseminated infection. It is not spread from person to person.
What are the symptoms of sporotrichosis?
The first symptom is usually a small painless bump resembling an insect bite. It can be red, pink, or purple in color. The bump (nodule) usually appears on the finger, hand, or arm where the fungus first enters through a break on the skin. This is followed by one or more additional bumps or nodules which open and may resemble boils. Eventually lesions look like open sores (ulcerations) and are very slow to heal. Pneumonia rarely occurs as a result of inhalation of fungal spores, and can cause symptoms such as shortness of breath, cough and fever. The infection can spread to other parts of the body, including bones and joints and the central nervous system.
Does sporotrichosis involve any other organs besides the skin?
The majority of infections are limited to the skin. Cases of joint, lung, and central nervous system infection have occurred but are very rare. Usually they occur only in persons with weakened immune system.
How soon do symptoms appear?
The first nodule may appear any time from 1 to 12 weeks after exposure to the fungus. Usually the nodules are visible within 3 weeks after the fungus enters the skin.
How is sporotrichosis diagnosed?
Sporotrichosis can be confirmed when a doctor obtains a swab or a biopsy of a freshly opened skin nodule and submits it to a laboratory for fungal culture.
If I have symptoms should I see my doctor?
Yes. It is important for the diagnosis to be confirmed by a doctor so that proper treatment can be provided.
How is sporotrichosis treated?
Itraconazole is the preferred treatment for cutaneous and lymphocutaneous sporotrichosis. It may also be used to treat bone and joint infections. For patients with severe disease, and/or pulmonary, central nervous system or disseminated infection, a lipid formulation of amphotericin B should be used initially. Itraconazole can be used for step-down therapy once the patient has stabilized. Potassium iodide (SSKI) is another option for cutaneous or lymphocutaneous disease that does not respond to itraconazole. SSKI and azole drugs like itraconazole should be avoided during pregnancy. Treatment recommendations may differ for children. Consult your doctor for more information.
Fluconazole is used in patients who do not respond to itraconazole. Systemic or disseminated infection is often treated with Amphotericin B, or sometimes itraconazole. Therapy for systemic disease can last up to 12 months.
How can sporotrichosis be prevented?
Control measures include wearing gloves and long sleeves when handling wires, rose bushes, hay bales, conifer (pine) seedlings, or other materials that may cause minor skin breaks. It is also advisable to avoid skin contact with sphagnum moss. Moss has been implicated as a source of the fungus in a number of outbreaks.
With treatment, full recovery can be expected. Disseminated sporotrichosis is more difficult to treat and requires chemotherapeutic agents. Disseminated sporotrichosis can be life-threatening for immunocompromised people.
Possible Complications (1)
In people with a normal immune system:
Secondary skin infections
In people who are immunosuppressed:
Lung and breathing problems (such as pneumonia)
Complications from medications — amphotericin B can have serious side effects
(1) Medline Plus