DETECTION OF PRO- INFLAMMATORY INTERLEUKIN 17 IN PATIENTS WITH L. TROPICA IN THI-QAR PROVINCE, IRAQ

Cutaneous leishmaniasis (CL) is a widespread health problem and considered one of the endemic diseases in Iraq. The dermal lesion occurs due to an obligate intracellular Leishmania parasite, which transmits by the bite of the infected female sandfly. This study aims to identify Leishmania species in Thi-Qar province/South of Iraq and detect IL-17 level in serum of infected patients with L. tropica. The study was conducted in three local locations, Al-Hussein Teaching, Al-Suq Al-Shyokh General, and Al-Shatrah General Hospitals in the province for the period from the beginning of November 2018 to the end of October 2019. After clinical diagnosis, eighty out of two hundred forty-seven samples were selected for molecular examination by nested-PCR technique, where the lesion edge was injected by normal saline and pulled again to obtain the parasite DNA. Also, a measure of the IL-17 concentration level in serum of the patients with ELISA. The findings of the electrophoresis of the kinetoplast minicircle DNA gene showed that 65 samples were positive for cutaneous leishmaniasis, and observed two species of Leishmania spp. in the study area, 46 (57.5%) samples were L. tropica at 750 bp and 19 (23.75%) samples were L. major. Serum IL-17 concentration recorded a significant increase among patients infected with L. tropica at different infection stages than control samples. Generally, the Nested-PCR technique is an accurate method for diagnosing clinical samples and molecular determination of Leishmania parasites. L. tropica is the dominant specie that caused CL in Thi-Qar province, while L. major recorded a low incidence.