New World cutaneous leishmaniasis in Adult
Cutaneous leishmaniasis results from infection of the skin with obligate intracellular parasites of the Leishmania genus. The parasites are transmitted by the bite of infected female phlebotomine sandflies (species in the Lutzomyia genus in the New World and in the Phlebotomus genus in the Old World). The World Health Organization (WHO) estimates that 1.5 million new cases of cutaneous leishmaniasis occur each year. Over 90% of the cases occur in the following countries:
Afghanistan, Algeria, Iran, Iraq, Saudi Arabia, and Syria.
Brazil and Peru.
However, the geographic areas of acquisition of infection for cases evaluated in the developed world reflect travel and immigration patterns.
NWCL typically is a zoonotic disease with various mammalian reservoir hosts. Humans are incidental hosts of infection. The most common leishmanial species that cause NWCL include those in the Leishmania mexicana complex (eg, L. mexicana, Leishmania amazonensis) and the Viannia subgenus; for example, Leishmania (V.) braziliensis, Leishmania (V.) panamensis, Leishmania (V.) guyanensis. The organisms in the Viannia subgenus and L. amazonensis may disseminate from the skin to the naso-oropharyngeal mucosa (ie, cause mucosal leishmaniasis).
The appearance and evolution over time of the skin lesions of NWCL can vary widely. Typically, the primary lesions are noted several weeks to months after the sandfly exposure and evolve thereafter, over weeks to months, from papular, to nodular, to ulcerative. Some lesions persist as nodules or plaques. Ultimately, over months to years, lesions may heal without therapy, leaving hypopigmented, atrophic scars. Lymphangitis that ascends the lymphatic chain and lymphadenopathy (sometimes bubonic) can be seen; the latter may precede the presence of skin lesions. Pruritus, pain, and bacterial superinfection may also be present. Systemic symptoms are rarely seen. Ultimately, over months to years, lesions may heal without therapy, leaving hypopigmented, atrophic scars. Reactivation of infection, typically first noted at the margins of scars, can occur months, sometimes years, after clinical resolutions of lesions.
Diffuse cutaneous leishmaniasis (DCL) is a rare variant caused by L. mexicana. It occurs in the context of leishmanial-specific anergy and is manifested by disseminated, nonulcerated lesions.
B55.1 – Cutaneous leishmaniasis
39625001 – Mucocutaneous leishmaniasis
- Tinea corporis
- Cutaneous tuberculosis
- Buruli ulcer
- Mycobacterium marinum infection
- Infection with other atypical mycobacteria
- Basal cell carcinoma
- Squamous cell carcinoma
- Foreign body reactions
- Traumatic ulcerations
- Superinfected arthropod bites