Conventional and ITS1 Gene-PCR Studies on Suspected Cutaneous Leishmaniasis Patients Referred to Different Public Health Hospitals in Quetta, Pakistan

Abstract

Background: Cutaneous leishmaniasis (CL) is a neglected tropical disease that remains endemic in several areas of Balochistan Province, including Quetta city. We aimed to evaluate the effectiveness of conventional and molecular diagnostic methods for the detection and identification of CL.

Methods: Overall, 100 suspected patients were examined using conventional techniques, including microscopy, culture, and histopathology during 2024-2025, from various public hospitals of Quetta city, Pakistan. In molecular methods ITS1 gene was used to detect Leishmania on species level. Specific primers of ITS1 gene were used to amplify the targeted regions.

Results: Microscopy and PCR amplification of the ITS1 gene confirmed CL infection in 86% of cases, Culture techniques yielded promastigote growth in 16 samples, while 14 slides showed histopathological effects, indicating comparatively lower detection rates. Molecular characterization through ITS1 sequencing revealed that the isolates shared a 99% and 100% similarity with Leishmania tropica. Phylogenetic analysis further supported this relationship, confirming the predominance of this species in the study area.

Conclusion: The findings highlight the limitations of conventional diagnostic methods and focus on the implication of molecular methods, particularly PCR, for exact and early detection of CL on species-level, which is critical for effective disease management and control strategies in endemic regions like Quetta. Other demographic characteristics such as gender, age, education status, and site of lesions were also recorded.