Sections View Full Chapter Figures Tables Videos Annotate Full Chapter Figures Tables Videos Supplementary Content + Download Section PDF Listen ++ For further information, see CMDT Part 35-03: Leishmaniasis + Key Features Download Section PDF Listen +++ +++ Essentials of Diagnosis ++ Sand fly bite in an endemic area Chronic, painless, moist ulcers or dry nodules Amastigotes in macrophages in aspirates, touch preparations, or biopsies Positive culture, serologic tests, polymerase chain reaction, or skin test +++ General Considerations ++ Transmitted by bites of sand flies of the genus Lutzomyia in the Americas and Phlebotomus elsewhere Caused by about 20 species of Leishmania; taxonomy is complex When sand flies feed on an infected host, the parasitized cells are ingested with the blood meal Clinical syndromes are generally dictated by the infecting species, but some species can cause more than one syndrome Old World cutaneous leishmaniasis is caused mainly by Leishmania tropica, Leishmania major, and Leishmania aethiopica in the Mediterranean, Middle East, Africa, Central Asia, and Indian subcontinent New World cutaneous leishmaniasis is caused by Leishmania mexicana and Leishmania amazonensis in Central and South America +++ Demographics ++ The estimated annual incidence of disease has been decreasing; current estimate is 700,000 to 1 million annual cases About 90% of cases of cutaneous leishmaniasis occur in Afghanistan Pakistan Syria Saudi Arabia Algeria Iran Brazil Peru + Clinical Findings Download Section PDF Listen +++ +++ Symptoms and Signs ++ Cutaneous swellings appears 1 weeks to several months after sand fly bites and can be single or multiple Characteristics of lesions and courses of disease vary depending on the leishmanial species and host immune response Lesions begin as small papules and develop into Nonulcerated dry plaques Large encrusted ulcers with well-demarcated raised and indurated margins Satellite lesions may be present The lesions are painless unless secondarily infected Local lymph nodes may be enlarged Systemic symptoms are uncommon, but fever, constitutional symptoms, and regional lymphadenopathy may be seen Leishmaniasis recidivans is a relapsing form of L tropica infection associated with hypersensitivity, in which the primary lesion heals centrally, but spreads laterally, with extensive scarring Diffuse cutaneous leishmaniasis Involves spread from a primary lesion with local dissemination of nodules and a protracted course Involves multiple nodular or ulcerated lesions, often with mucosal involvement +++ Differential Diagnosis ++ Hansen disease (leprosy) Fungal infection Cutaneous tuberculosis Neoplasm Syphilis, yaws Sarcoidosis L donovani [see Leishmaniasis, Visceral (Kala Azar)] + Diagnosis Download Section PDF Listen +++ +++ Laboratory Tests ++ Identifying amastigotes within macrophages in tissue samples provides a definitive diagnosis Biopsy specimens should be taken from raised border of skin lesion, with samples for histopathology, touch preparation, and culture Histopathology shows inflammation with mononuclear cells Macrophages filled with amastigotes may be present, especially early in infection Intradermal leishmanin (Montenegro) skin test Positive in most individuals with cutaneous disease but negative in those with progressive visceral or diffuse cutaneous disease This test is not approved in the United States + Treatment Download Section PDF Listen +++ +++ Medications +++ OLD WORLD CUTANEOUS LEISHMANIASIS ++ Generally self-healing over some months Does not metastasize to the mucosa May be justified to withhold treatment in regions without mucocutaneous disease if lesions are small and cosmetically unimportant Lesions on the face or hands are generally treated +++ NEW WORLD CUTANEOUS LEISHMANIASIS ++ Has a greater risk of progression to mucocutaneous disease, so treatment is more often warranted Standard therapy is with pentavalent antimonials for 20 days (see Leishmaniasis, Visceral [Kala Azar]) Other treatments include Azole antifungals Miltefosine Allopurinol Topical therapy has included Intralesional antimony Intralesional pentamidine Paromomycin ointment Cryotherapy Local heat Surgical removal Diffuse cutaneous leishmaniasis and related chronic skin processes generally respond poorly to therapy + Outcome Download Section PDF Listen +++ +++ Prognosis ++ For most species, healing occurs spontaneously in months to a few years, but scarring is commonly seen +++ Prevention ++ Avoidance of sand fly bites by Using insect repellants and fine-mesh insect netting Wearing long sleeves and pants Avoiding warm shaded areas where flies are common Disease control measures include Destroying animal reservoir hosts Mass treatment of humans in disease-prevalent areas Spraying residual insecticide in dwellings Limiting contact with dogs and other domesticated animals Using permethrin-impregnated collars for dogs + References Download Section PDF Listen +++ + +Burza S et al. Leishmaniasis. Lancet. 2018 Sep 15;392(10151):951–70. [PubMed: 30126638] + +Rubiano LC et al. Noninferiority of miltefosine versus meglumine antimoniate for cutaneous leishmaniasis in children. J Infect Dis. 2012 Feb 15;205(4):684–92. [PubMed: 22238470] + +Torres-Guerrero E et al. Leishmaniasis: a review. F1000Res. 2017 May 26;6:750. [PubMed: 28649370]