Natural infection of North African gundi (Ctenodactylus gundi) by Leishmania tropica in the focus of cutaneous leishmaniasis, Southeast Tunisia.

North African gundis (Ctenodactylus gundi) were trapped in the Leishmania (L.) tropica focus of cutaneous leishmaniasis, situated in southeast Tunisia and evaluated for Leishmania infection by real-time kinetoplast DNA polymerase chain reaction (PCR). Species identification was performed by internal transcribed spacer one (ITS1)-PCR-restriction fragment length polymorphism (RFLP) and high-resolution melting (HRM) analysis of the 7SL RNA gene. Real-time PCR on blood was positive in 6 of 13 (46.2%) tested gundis. Leishmania tropica was identified in five infected gundis and Leishmania major in one specimen. Alignments of the ITS-1 DNA sequences and 7S-HRM curves analysis indicated that similar genotypes were present in humans, a sandfly, and gundis from the same region suggesting a potential role of this rodent as reservoir host of L. tropica in southeast Tunisia.

First report on natural infection of Phlebotomus sergenti with Leishmania promastigotes in the cutaneous leishmaniasis focus in southeastern Tunisia.

During September 2010, 133 female sand flies were caught inside houses of patients with cutaneous leishmaniasis in the focus for this disease in southeastern Tunisia and subsequently dissected. One specimen was positive for Leishmania protozoa. This sand fly species was identified as Phlebotomus sergenti, and the parasite was identified as L. tropica. This is the first report of P. sergenti involvement in transmission of L. tropica in Tunisia.

Advantages and limits of real-time PCR assay and PCR-restriction fragment length polymorphism for the identification of cutaneous Leishmania species in Tunisia.

Cutaneous leishmaniasis (CL), a public health problem in Tunisia, is associated to three species: Leishmania (L.) infantum, L. major and L. killicki. Accurate and sensitive procedures for the diagnostic of Leishmania infection and for species identification are required to enable adequate treatment and appropriate control measures. Several PCR-methods are applied for the diagnosis and the identification of Leishmania parasites such as PCR-restriction fragment length polymorphism (PCR-RFLP), DNA sequencing, hybridization probes and real-time PCR (RT-PCR). In this study, PCR-RFLP and RT-PCR were performed on skin scrapings from 27 patients with confirmed CL by microscopic examination, in order to compare their usefulness and efficiency for identification of Leishmania species in routine diagnostic laboratories. Identification of Leishmania species was successfully achieved in 96.3% and 81.5% respectively. Agreement between using internal transcribed spacer 1 (ITS1)-PCR-RFLP and kDNA-RT-PCR assays was 70% (19/27). Characterization problems using RT-PCR were mainly due to the difficulties in analyzing the melting temperatures. ITS1-PCR-RFLP and kDNA-RT-PCR presented an interesting alternative to conventional methods for the identification of Leishmania parasites from clinical samples. Both PCR assays can be used in a routine diagnostic, however, further prospective studies including largest sampling, are required to determine their performances in a routine use.

Epidemiologic and clinical features of cutaneous leishmaniasis in southeastern Tunisia.

Species-specific diagnosis was performed in 66 patients with cutaneous leishmaniasis (CL) living in Tataouine focus in southeastern Tunisia. Leishmania DNA was extracted directly from dermal scrapings (n = 66) and from parasites obtained in culture (n = 12). Species were identified by using polymerase chain reaction-restriction fragment length polymorphism analysis for internal transcribed spacer region 1 and isoenzyme analysis. Leishmania tropica and L. major were identified in 31 (47%) and 35 (53%) cases respectively. Leishmania tropica CL cases were geographically scattered, and L. major CL cases were clustered. Lesions caused by L. tropica were mostly single (83.8%) and face-localized (55.8%), and lesions caused by L. major were multiple (57.1%; P < 0.001) and situated on limbs (83.7%; P < 0.001). For both species, most lesion onsets were reported during June-January. However, lesions that emerged during February-May were mainly caused by L. tropica (83.3%; P < 0.01). Moreover, the delay before seeking medical advice was higher for L. tropica infections than for L. major infections (P < 0.05).