Inter- and Intraspecific Variations of Leishmania Strains Isolated from Patients with Cutaneous and Visceral Leishmaniases in Fars Province, South of Iran

Cutaneous and visceral leishmaniases are present in Fars Province in the south of Iran. The current study aimed to evaluate the inter- and intragenic diversities of Leishmania species isolated from patients with leishmaniasis in Fars Province, using PCR-based analyses and DNA sequencing of the N-acetylglucosamine-1-phosphate transferase (nagt) gene.
Clinical samples were taken from the skin lesions of 120 individuals with clinical suspicion of cutaneous leishmaniasis (CL) referred to the major health centers of Shiraz. Along with microscopic examination, a part of each sample was used for in vitro cultivation. DNA was extracted from the cultured parasites and the nagt gene was PCR-amplified. For RFLP analysis, the PCR product of the nagt gene was digested with the Acc1 restriction enzyme. Moreover, the PCR products of 23 isolates were sequenced and analyzed, using MEGA5.
From the 120 patients with clinical suspicion of CL, 110 (91.7%) cases were found to be positive by direct microscopy while 77 (64.1%) of the cultures were positive. Digestion of the PCR product with the Acc1 restriction enzyme detected L. major in 57 out of the 77 (74.1%) and L. tropica, in 20 out of the 77 (25.9%) cases with CL. Phylogenetic analysis grouped the Leishmania isolates into 3 main clades, representing L. major, L. infantum, and L. tropica, encompassing 2, 2, and 2 haplotypes, respectively. Within the clades, the L. tropica intraspecies divergence was more pronounced in L. major.
The findings of this study demonstrated that the causative agent of CL in Fars Province was mainly L. major and that there was considerable heterogeneity between the Leishmania species and also within the L. major isolates.