Skin lesion of histoplasmosis Health Article

Definition

A histoplasmosis infection, which is caused by the fungus Histoplasma capsulatum, can result in skin lesions.

Causes, incidence, and risk factors

Histoplasmosis is a widespread fungal infection that occurs worldwide. The infection gets into the body through the lungs.

Histoplasma grows in soil. The fungal particles become airborne, and are breathed into the lung. Soil contaminated with bird or bat droppings may have a higher concentration of the fungus.

The skin lesions can be caused by an immune reaction to the lung infection. In this case, lesions called erythema nodosum or erythema multiforme occur.

Skin lesions can also occur when the fungus has spread to distant organs throughout the body, including the skin, bone marrow, and the brain. This is most common among immunosuppressed people, such people with AIDS.

Symptoms

The symptoms may include:

• Mouth ulcer, usually painless
• Pustules or nodules throughout the body
• Other symptoms related to erythema nodosum and erythema multiforme

Signs and tests

In some cases, a biopsy of the skin lesion can identify the fungus. On the other hand, erythema nodosum and erythema multiforme skin lesions are inflammatory reactions and usually do not have fungus in them.

Treatment

Anti-fungal drugs, such as amphotericin B, itraconazole, and ketoconazole, are the usual treatments. Anti-fungals may be given intravenously depending on the form or stage of disease. In some cases, long-term treatment with anti-fungal drugs may be used.

Expectations (prognosis)

The outlook depends on the form of histoplasmosis and the condition of the individual's immune system. Death can occur in some cases.

Complications

• Bacterial skin infection
• Complications of medications (for example, amphotericin B can have severely unpleasant side effects)

Calling your health care provider

The skin lesions may be similar to skin problems from other infections or illnesses. Notify your health care provider if you develop any suspicious lesions on your skin, so that you may be tested correctly.

Prevention

Histoplasmosis may be prevented by reducing exposure to dust in chicken coops, bat caves, and other infected locations. Wear masks and other protective equipment if you work in these environments.

References

Wheat JL. Histoplasmosis: a review for clinicians from non-endemic areas. Mycoses 2006;49 (4),274-82.