title: Evidence for leishmania (viannia) parasites in the skin and blood of patients before and after treatment.
abstract: BACKGROUND
  American cutaneous leishmaniasis is considered to be a zoonotic disease transmitted by sand flies that feed on infected sylvatic mammals. However, the "domestication" of transmission and the increase in treatment failure with antimonial drugs have raised the suspicion of anthroponotic transmission of American cutaneous leishmaniasis.
  
  
  METHODS
  The objective of the present study was to explore the potential of humans as a source of infection for sand flies. Biological (xenodiagnosis and culture) and molecular (polymerase chain reaction/Southern blot) detection methods were used to evaluate peripheral-blood monocytes and tissue fluids from sites accessible to sand flies from 59 adult patients with parasitologically confirmed American cutaneous leishmaniasis.
  
  
  RESULTS
  Overall, 44.1% of patients (26/59) presented biological and/or molecular evidence of Leishmania parasites in normal skin, peripheral-blood monocytes, lesion scars, or lesion border (by xenodiagnosis) before (18/59 [30.5%]) or after (10/27 [37.0%]) treatment. Leishmania parasites were cultured from the unaffected skin of 2 (3.6%) of 55 patients, and xenodiagnosis gave positive results for 5 (8.8%) of 57 patients before treatment.
  
  
  CONCLUSIONS
  The presence of Leishmania parasites in the unaffected skin and peripheral-blood monocytes of a high proportion of patients even after treatment and the acquisition of infection by sand flies support the plausibility of anthroponotic transmission of American cutaneous leishmaniasis.
authors.affiliation: Centro Internacional de Entrenamiento e Investigaciones Medicas, Cali, Valle, Colombia.
authors.forename: Carolina
authors.initials: C
authors.lastname: Vergel
authors.forename: Ricardo
authors.initials: R
authors.lastname: Palacios
authors.forename: Horacio
authors.initials: H
authors.lastname: Cadena
authors.forename: Claudia Jimena
authors.initials: CJ
authors.lastname: Posso
authors.forename: Liliana
authors.initials: L
authors.lastname: Valderrama
authors.forename: Mauricio
authors.initials: M
authors.lastname: Perez
authors.forename: John
authors.initials: J
authors.lastname: Walker
authors.forename: Bruno Luis
authors.initials: BL
authors.lastname: Travi
authors.forename: Nancy Gore
authors.initials: NG
authors.lastname: Saravia
mesh_terms: D000293:Adolescent; D000328:Adult; D000818:Animals; D000981:Antiprotozoal Agents / Q000627:therapeutic use; D002921:Cicatrix / Q000469:parasitology; D016054:DNA, Protozoan / Q000032:analysis; D004197:Disease Reservoirs; D005260:Female; D006801:Humans; D007303:Insect Vectors / Q000469:parasitology; D007891:Leishmania / Q000302:isolation & purification*; D016773:Leishmaniasis, Cutaneous / Q000188:drug therapy / Q000469:parasitology* / Q000635:transmission*; D007963:Leukocytes, Mononuclear / Q000469:parasitology; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D011576:Psychodidae / Q000469:parasitology; D012867:Skin / Q000469:parasitology
chemical_list: D000981:Antiprotozoal Agents; D016054:DNA, Protozoan