Comparison of clinical samples and methods in chronic cutaneous leishmaniasis

Abstract

This study aimed at finding out the most effective clinical samples and methods in chronic cutaneous leishmaniasis (CCL). Smear, aspiration fluid, and filter paper samples were taken from 104 skin lesions of suspected cases with CCL, and they were compared using microscopic examination, culture, and molecular methods. We characterized four different forms of CCL and identified the causative agents in CCL forms using high-resolution melting curve real-time polymerase chain reaction assay. We observed that smear was detected to be the most sensitive (63.5%) among clinical samples, and real-time polymerase chain reaction method was the most sensitive (96.8%) among the methods used in diagnosis of CCL. We identified 68.8% Leishmania tropica and 31.2% L. infantum in papular lesions, 69.2% L. infantum and 30.8% L. tropica in nodular lesions, 57.9% L. tropica and 42.1% L. major in ulcerating plaque lesions, and 55.5% L. tropica and 44.5% L. major in noduloulcerative lesions in CCL patients.

© The American Society of Tropical Medicine and Hygiene.

Figures

Figure 1.

Venn diagram with data about PCR, real-time PCR, and parasitologic examination (PE; microscopic examination and culture) positivity regarding CCL-suspected cases (N = 104 CCL-suspected cases). The analysis of positivity for PE, PCR, and real-time PCR in patients suspected of CCL shows that one, one, and three patients were positive exclusively in each one of the methods, respectively, and that 38 patients were positive and 35 patients were negative in all three methods. AS = aspiration fluids; CU = culture; FP = filter paper; ME = microscopic examination; OD = other dermatologic diseases; S = smear.