Diseases

Sporotrichosis Information

Definition of Sporotrichosis

Sporotrichosis is an infection caused by a fungus called Sporothrix schenckii. The fungus lives throughout the world in soil, plants, and decaying vegetation. Cutaneous (skin) infection is the most common form of infection, although pulmonary infection can occur if a person inhales the microscopic, airborne fungal spores. Most cases of sporotrichosis are sporadic and are associated with minor skin trauma like cuts and scrapes; however, outbreaks have been linked to activities that involve handling contaminated vegetation such as moss, hay, or wood.

Diagnosis and Testing

Sporotrichosis is typically diagnosed when your doctor obtains a swab or a biopsy of the infected site and sends the sample to a laboratory for a fungal culture. Serological tests are not always useful in the diagnosis of sporotrichosis due to limitations in sensitivity and specificity.

Sources

The fungus lives in sphagnum moss, hay, other plant materials, and soil. The fungus can enter the skin through small cuts or punctures from thorns, barbs, pine needles, or wires. In rare cases, inhalation of the fungus can cause pulmonary infection. Sporotrichosis is not spread from person to person; however, a small number of human cases have been caused by scratches or bites from infected animals such as cats.

Sporotrichosis facts*

*Sporotrichosis facts medical author: Charles Patrick Davis, MD, PhD

• Sporotrichosis (also termed rose gardener's or rose handler's disease) is an infection caused by the fungus Sporothrix schenckii, found throughout the world; it is usually associated with minor skin cuts and scrapes that occur when handling vegetation (moss, hay, wood, sharp-stemmed plants like rosebushes).
• The first symptom of sporotrichosis is usually a small bump on the arm, finger, or hand that may occur about one to 12 weeks after exposure; the bump or nodule eventually comes larger and resembles a sore or ulcer. Immunodepressed individuals develop disseminated infections and/or pneumonia that can cause shortness of breath, cough, and fever.
• Risk factors include people who handle plants like rosebushes and other items, such as moss or bales of hay; vocational outbreaks have occurred with rose gardeners, greenhouse workers, and/or children playing on bales of hay.
• There is no vaccine to prevent sporotrichosis; individuals can reduce exposure by wearing gloves and long-sleeved shirts to prevent small cuts or abrasions that allow the fungi into the skin.
• Rarely, inhalation of the fungi can cause pulmonary infections; there is no person-to-person spread, but infections have occurred from scratches or bites by animals, such as cats.
• Sporotrichosis is usually diagnosed by swabbing or taking a biopsy of an infected site that is sent for fungal culture.
• The usual treatment for sporotrichosis is oral itraconazole (Sporanox) for about three to six months; other treatments include supersaturated potassium iodide and amphotericin B in patients with more severe disease.
• The incidence worldwide of sporotrichosis is unknown, but there have been outbreaks in the U.S., Western Australia, Brazil, and Peru, for example. The fungi Sporothrix schenckii is associated with soil and plant matter.

Statistics

The exact incidence of sporotrichosis is unknown, but people at increased risk for sporotrichosis usually have occupational or recreational exposures related to agriculture, horticulture, forestry, or gardening.Sporothrix schenckii can be found throughout the world in soil and plant matter. Peru is suspected to be an area where S. schenckii is extremely common in the environment. Outbreaks of sporotrichosis have been documented in the United States, Western Australia, and Brazil.

Symptoms of Sporotrichosis

The first symptom is usually a small painless nodule (bump) resembling an insect bite. The first nodule may appear any time from 1 to 12 weeks after exposure to the fungus. The nodule can be red, pink, or purple in color, and it usually appears on the finger, hand, or arm where the fungus has entered through a break in the skin. The nodule will eventually become larger in size and may look like an open sore or ulcer that is very slow to heal. Additional bumps or nodules may appear later near the original lesion.Most Sporothrix infections only involve the skin. However, the infection can spread to other parts of the body, including the bones, joints, and the central nervous system. Usually, these types of disseminated infections only occur in people with weakened immune systems. In rare cases, a pneumonia-like illness can occur after inhaling Sporothrix spores, which can cause symptoms such as shortness of breath, cough, and fever.If you think you have sporotrichosis, you should see a healthcare provider.

Treatment and Outcomes

Most cases of sporotrichosis only involve the skin and/or subcutaneous tissues and are non-life-threatening, but the infection requires treatment with prescription antifungal medication for several months. The most common treatment for this type of sporotrichosis is oral itraconazole for 3 to 6 months. Itraconazole may also be used to treat bone and joint infections, but treatment should continue for at least 12 months.For patients with severe disease, and/ or an infection that has spread throughout the body, a lipid formulation of amphotericin B should be used. Itraconazole can be used for step-down therapy once the patient has stabilized. Supersaturated potassium iodide (SSKI) is another treatment option for cutaneous or lymphocutaneous disease. SSKI and azole drugs like itraconazole should not be used during pregnancy. Treatment recommendations may differ for children.