Sporotrichosis

Background

• Also known as "Rose gardener's disease"
• Caused by the fungus Sporothrix schenckii
• Usually affects skin, although other rare forms can affect the lungs, joints, bones, and brain
• Enters skin through small cuts and abrasions, and inhalation for pulmonary disease
• Can also be acquired from handling cats with the disease

Clinical Features

Progresses slowly: first symptoms may appear 1 to 12 weeks (average 3 weeks) after the initial exposure to the fungus

Forms and symptoms

• Cutaneous or skin sporotrichosis

This is the most common form of this disease. Symptoms of this form include nodular lesions or bumps in the skin, at the point of entry and also along lymph nodes and vessels. The lesion starts off small and painless, and ranges in color from pink to purple. Left untreated, the lesion becomes larger and look similar to a boil and more lesions will appear, until a chronic [ulcer develops.

Usually, cutaneous sporotrichosis lesions occur in the finger, hand, and arm.

• Pulmonary sporotrichosis

This rare form of the disease occur when S. schenckii spores are inhaled. Symptoms of pulmonary sporotrichosis include productive coughing, nodules and cavitations of the lungs, fibrosis, and swollen hilar lymph nodes. Patients with this form of sporotrichosis are susceptible to developing tuberculosis and pneumonia

• Disseminated sporotrichosis

When the infection spreads from the primary site to secondary sites in the body, the disease develops into a rare and critical form called disseminated sporotrichosis. The infection can spread to joints and bones (called osteoarticular sporotrichosis) as well as the central nervous system (sporotrichosis meningitis)

The symptoms of disseminated sporotrichosis include weight loss, anorexia, and appearance of bony lesions.

Workup

Fungal culture of skin, sputum, synovial fluid, or CSF

Management

• Saturated potassium iodide solution

Although its mechanism is unknown, application of potassium iodide in droplet form can cure cutaneous sporotrichosis. This usually requires 3 to 6 months of treatment.

• Itraconazole (Sporanox) and fluconazole

These are antifungal drugs. Itraconazole is currently the drug of choice and is significantly more effective than fluconazole. Fluconazole should be reserved for patients who cannot tolerate itraconazole.

• Amphotericin B

This antifungal medication is delivered intravenously. Many patients, however, cannot tolerate Amphotericin B due to its potential side effects of fever, nausea, and vomiting.

Lipid formulations of amphotericin B are usually recommended instead of amphotericin B deoxycholate because of a better adverse-effect profile. Amphotericin B can be used for severe infection during pregnancy. For children with disseminated or severe disease, amphotericin B deoxycholate can be used initially, followed by itraconazole.

In case of sporotrichosis meningitis, the patient may be given a combination of Amphotericin B and 5-fluorocytosine/Flucytosine.

• Newer triazoles

Several studies have shown that posaconazole has in vitro activity similar to that of amphotericin B and itraconazole; therefore, it shows promise as an alternative therapy. However, voriconazole susceptibility varies. Because the correlation between in vitro data and clinical response has not been demonstrated, there is insufficient evidence to recommend either posaconazole or voriconazole for treatment of sporotrichosis at this time.

• Surgery

In cases of bone infection and cavitatory nodules in the lungs, surgery may be necessary.

Sometimes become superinfected

Disposition

• Normally treated as outpatient