Old World leishmaniasis is usually limited to the skin, whereas New World leishmaniasis can cause mutilating mucocutaneous involvement. After a period of months to years, the mucocutaneous, or secondary, form of the disease may develop, depending on host immunologic factors. Lesions in this stage range from edema of the lips and nose to perforation of the nasal cartilage. A rare form, disseminated cutaneous leishmaniasis, which has widespread nodules resembling lepromatous leprosy, may occur in immunosuppressed patients. The differential diagnosis includes various inflammatory and neoplastic disorders, including squamous cell carcinoma.
Diagnosis is made by skin biopsy with histopathologic examination.
Appropriate therapy depends on species identification. A pentavalent antimony compound, such as sodium stibogluconate, is the drug of choice for New World leishmaniasis, which tends to be more aggressive. Lesions acquired in the Middle East and North Africa may spontaneously involute or may respond to local therapy, including cryosurgery, heat therapy, or intralesional injection of antimonials. They may have excoriations or skin inflammation and erosions consistent with factitial dermatitis. Frequently, patients will bring small containers filled with lint, hairs, pieces of skin, fibers, or other debris for examination.