Molecular and parasitological study of cutaneous leishmaniasis in Bushehr province, southwest of the Islamic Republic of Iran: a cross-sectional study during 2009-2012.

Abstract

Cutaneous leishmaniasis (CL) is one of the most important parasitic disease in Iran. CL is distributed among more than half of 31 provinces of Iran. Studies on epidemiological aspects of the disease and Leishmania species identification among infected humans are necessary for providing a comprehensive prevention and control program thus; this descriptive cross-sectional study was conducted on all CL suspected patients who referred to Health Centers of Bushehr province from 2009 to 2012. Physical examinations were carried out in suspected individuals and CL cases were confirmed by microscopical examinations. Prepared slides from suspicious cases of CL were fixed with absolute methanol and stained by Giemsa 10%. All the Giemsa-stained slides examined under a light microscope with high magnification (1,000×) and classified them based on grading of Leishmania parasites. DNA from each slide was extracted, separately. The ribosomal internal transcribed spacer 1 was amplified with specific primers and PCR products were digested by restrict enzymes (HaeIII), run them in 3% gel agarose for electrophoresis and visualized on a UV transilluminator after staining with ethidium bromide. SPSS version 21 was used for data analyses. A total of 726 suspected CL cases were referred to Health Centers of Bushehr province from 2009 to 2012 and samples were only prepared from 188 of the patients whereas 43 (5.9%) of them were microscopy positive. The most frequent of CL was observed in November (14%) and December (12%). The most distribution of CL lesions were observed on hands (32%), feet (26%), and face (21%), respectively. The highest frequency of CL was observed in 1-9years old (30%). Altogether, 50% of the patients showed one skin lesion and 2-10 skin lesions were occurred in the remained CL patients. Totally, 27 out of 43 (63%) of the Giemsa stained slides were positive by PCR-RFLP assay because all the PCR-RFLP negative slides were prepared 3-4years ago and kept without cover slip, and also observed scarce amastigotes during microscopy observations. Leishmania species were identified in 21 desirable slides which 14 of them were L. major and 7 of the remained isolates were identified L. tropica using PCR-RFLP.