A 14-year-old girl was referred with an 8-year history of a scarring rash on her left cheek that began, while living in Afghanistan, as a red bump (Fig 1). Additional red bumps developed, followed by ulceration at the site over the next 6 months. Thereafter, the site was stable, but it had scarred and the red bumps persisted.
A 20-year-old man presented with an ulcerated lesion on his right forehead that had developed from a "pimple" during the previous 2 to 3 months (Fig 2). Two months before onset of the lesion, he had traveled in Central America. Figure 3 shows a biopsy specimen from the forehead lesion of the patient in Fig 2.
Denouement and Discussion
Cutaneous Leishmaniasis
Epidemiology
Leishmaniasis is a major cause of morbidity throughout the world, with an annual incidence of approximately 400 000 persons. Leishmania species are protozoans that are transmitted by female arthropods and flies, usually at night, while the sand fly feeds on its particular vertebrate host, which may include humans. In endemic areas of the Old World, the rate of cutaneous infection in children with the Leishmania tropica or Leishmania major complexes may approach 100%. Cutaneous leishmaniasis in the New World is caused by subspecies of the Leishmania braziliensis or Leishmania mexicana complexes and is most common when a human enters a previously undisturbed forest.