Leishmaniasis caused by Leishmania (Viannia) guyanensis in north-central Pacific region of Ecuador: A clinico-epidemiological feature

Acta Trop. 2018 Sep:185:204-211. doi: 10.1016/j.actatropica.2018.05.016. Epub 2018 May 28.

Abstract

The current four year study was undertaken to investigate the clinical and epidemiological features of Leishmania (Viannia) guyanensis infections in Valle Hermoso, Santo Domingo de Los Tsachilas province, north-central Pacific areas of Ecuador. A total of 155 parasitologically confirmed (Leishmania-amastigote-positive) clinical cases diagnosed at a rural health center during January 2014-December 2017 were analyzed thoroughly. Molecular characterization of the causative Leishmania parasites from different endemic sites within the study areas was performed by PCR amplification of cytochrome b (cyt b) sequencing. All the FTA-card and/or smear impregnated materials tested were characterized, and identified as L. (V.) guyanensis, without detecting any other Leishmania species. The following features were described: 1) the majority of patients were suffered from a single ulcer lesion (simple and mild to chronic), followed by multiple lesions, including recidiva cutis-"like" and Chiclero's ulcer-"like" clinical forms; 2) the majority (65.70%) of lesions were less than 10 mm in size, and distributed mainly on the upper body regions (arm, forearm, face, and neck including ear and head); 3) about 30% (29.68%) of the subjects tested were less than 10 years of age, strongly suggesting the intra- and/or peri-domestic transmission of the disease in the areas. The current clinico-epidemiological feature detected emphasizes the need for further such investigations of the L. (V.) guyanensis infections prevalent at different Pacific ecoregions of Ecuador, including Amazon regions.

Keywords: Amastigote-positive cases; Clinico-epidemiology; Ecuador; Leishmania (Viannia) guyanensis; PCR.

MeSH terms

  • Adolescent
  • Adult
  • Aged
  • Animals
  • Child
  • Child, Preschool
  • Cytochromes b / genetics
  • Ecuador / epidemiology
  • Female
  • Humans
  • Infant
  • Leishmania guyanensis* / genetics
  • Leishmania guyanensis* / isolation & purification
  • Leishmaniasis, Mucocutaneous / epidemiology*
  • Leishmaniasis, Mucocutaneous / transmission
  • Male
  • Middle Aged
  • Prevalence
  • Young Adult

Substances

  • Cytochromes b