Molecular Epidemiology of Leishmania ( Viannia ) guyanensis in French Guiana

Abstract

Little information is available about the genetic variability of Leishmania populations and the possible correlations with ecoepidemiological features of leishmaniases. The present study was carried out in French Guiana, a country where cutaneous leishmaniases (CL) are endemic over the whole territory. The genetic polymorphism of a nuclear sequence encompassing the end of the ribosomal small subunit and the internal transcribed spacer 1 of 265 isolates from patients with CL was examined by restriction fragment length polymorphism analysis. Genotypes based on the fingerprinting phenetic integration were compared to epidemiological, clinical, and geographical data. In agreement with previous reports, five different Leishmania species were identified, but Leishmania (Viannia) guyanensis represented 95.8% of the samples. Two distinct L. (V.) guyanensis populations were found to originate in two ecologically characterized regions. Higher lesional parasite densities and the need for additional treatments were significantly linked to genotype group I. Parasites of genotype group II were more likely to cause chronic and disseminated cutaneous forms in patients. L. (V.) guyanensis was previously said not to be very polymorphic; however, the present analysis resulted in a significant degree of discrimination among L. (V.) guyanensis isolates from diverse ecological areas and with different clinical implications.In the highly biodiversified region of the New World (NW) that encompasses the northern Amazon Basin and the Guiana Shield, at least seven named species belonging to the Leishmania genus coexist with often overlapping hosts and vectors (39). American visceral leishmaniases due to Leishmania (Leishmania) infantum are found there, but cases of cutaneous leishmaniases (CL) are far more numerous. Human cutaneous infections may be unapparent; however, many of the Leishmania parasites are able to produce a spectrum of diseases rather than a single clinical form. Cases reported in that region range from localized and diffuse cutaneous forms to mucocutaneous leishmaniases. They are now being reported in areas where leishmaniases had previously not been endemic (2, 17): increasing risk factors related to natural and especially manmade environmental changes are making leishmaniases a growing public health concern in this particular region. However, little information is available about the genetic variability of parasite populations and the possible correlation with ecoepidemiological features of the diseases. The present study was carried out in French Guiana, a country where CL are endemic over the whole territory (incidence of 0. 2% between 1979 and 2000 [6, 14]). The genetic polymorphism of a nuclear sequence encompassing the end of the ribosomal small subunit (SSU) and the internal transcribed spacer 1 (ITS1) of 265 samples from patients with CL was examined by restriction fragment length polymorphism (RFLP) analysis. Genotypes based on the fingerprinting phenetic integration were then compared to epidemiological, clin...

Randomized Controlled Clinical Trial to Access Efficacy and Safety of Miltefosine in the Treatment of Cutaneous Leishmaniasis Caused by Leishmania (Viannia) guyanensis in Manaus, Brazil

“…A study performed in the French Guiana using ribosomal fingerprinting analysis identified two distinct nonsympatric L. ( V. ) guyanensis populations. 17 The genotype 1 was associated with higher parasite density in lesions and the need for additional treatments. Differences in L. ( V. ) guyanensis subpopulations were also found by Romero and others in isolates from his previous study reported previously.…”

Prevalence and Distribution of Leishmania RNA Virus 1 in Leishmania Parasites from French Guiana

“…14 In French Guiana, Leishmania species predominantly diagnosed are L. guyanensis, L. braziliensis, and occasionally Leishmania amazonensis (Simon and others, submitted data). 15 Leishmaniasis represents a significant risk for those in contact with the forest. Our study aimed to determine the prevalence of LRV1 in the circulating isolates of Leishmania spp.…”

Identification of Leishmania spp. by Molecular Amplification and DNA Sequencing Analysis of a Fragment of rRNA Internal Transcribed Spacer 2

“…Molecular approaches have the potential to be more sensitive and rapid; e.g., the results can be available within days versus weeks or months. However, Leishmania PCR-based assays have varied in sensitivity, specificity, and utility for genus-or complexlevel versus species-level characterization (2,3,7,10,(24)(25)(26)28); some approaches have been highly sensitive for genuslevel detection, e.g., PCR methods that target minicircle kinetoplast DNA (kDNA), whereas others have been tailored for particular species/settings.…”