[Identification of mutation for drug resistance gene in cutaneous leishmaniasis]

Cutaneous leishmaniasis is a common parasitic disease and one of the health problems world wide. The pentavalent antimonial drugs [e.g. pentostam and Glucantime] are the first line treatment for leishmaniasis, and resistance to these drugs is a serious problem. Using PCR method, this study was carried out to identify the mutation for sodium stibogluconate resistance gene in cutaneous leishmaniasis cases referred to different health centers during 2006-8. This descriptive study was conducted on 150 isolates of leishmania major and leishmania tropica to identify the mutation in drug resistance gene. Promastigote clones were cultured in enriched RPMI 1640 medium and then the genomic DNA was isolated and using a pair of primers, a 400 bp of the gene was amplified. Finally, the PCR products were screened by conformation sensitive gel electrophoresis [CSGE] method and then the mutation was confirmed using RFLP with Sdu1 enzyme. Screening using CSGE and RFLP methods showed that 6.3% of the samples carried a mutation for drug resistance gene. Results showed a resistance for cutaneous leishmania against sodium stibogluconate. Further studies are required to determine the biochemical mechanism of this resistance

[Detection of drug resistance gene in trichomonas vaginalis by PCR]

Trichomoniasis is a worldwide protozoan parasitic disease. Considering the importance of the disease in public health and the controversial ideas about the prevalence of drug resistance, this study was designed to determine the prevalence of metronidazole resistance gene in trichomonas vaginalis [T. vaginalis] with PCR-RFLP method in Tehran and in Kashan. In this descriptive study 140 samples of T. vaginalis in patients with T. vaginalis infections were collected and assessed microscopically. Then they were isolated and examined by culturing in dorset's medium, DNA extraction and PCR amplification. The PCR products were analyzed using RFLP and suspected samples were sequenced. All but 7 samples were T. vaginalis positive by PCR. Sixty-two samples [44.4%] were examined by microscopic, culture and PCR techniques; 12 samples [8.5%] by microscope and PCR, 56 samples [40%] by culture and PCR and other 3 samples [2.1%] were positive only by PCR. Two samples [1.5%] were also examined for detection of mutation in 18S rRNA gene with RFLP in Tehran. This study shows that T. vaginalis infections in the female population living in Tehran are metronidazole-resistant. Since metronidazole is considered as the drug choice for T. vaginalis infections, more studies are recommended for identification of the drug resistance mechanisms and prevention of the disease