Diagnosis of Mediterranean Visceral Leishmaniasis by Detection of Leishmania Antibodies and Leishmania DNA in Oral Fluid Samples Collected Using an Oracol Device

Abstract

Current methods for diagnosis of visceral leishmaniasis (VL) require invasive sampling procedures such as visceral aspiration and/or blood drawing. The use of diagnostic tests using oral fluid, which is easier to collect, would be more simple and practical for VL diagnosis, especially under field conditions. Oral fluids from 37 VL patients and 40 healthy controls were collected using Oracol devices. Blood samples and oral fluid specimens from both groups were analyzed by recombinant protein K39 (rK39) enzyme-linked immunosorbent assay and quantitative real-time PCR. Detection of antibodies in the oral fluid had a sensitivity of 100% and a specificity of 97.5%. Antibody levels measured in serum and oral fluid showed a significant positive correlation ( ‫؍‬ 0.655 and P ‫؍‬ 0.01). Detection of Leishmania DNA in oral fluid had a sensitivity of 94.6% and a specificity of 90%. The median parasite load estimated in blood was 133 parasites/ml (interquartile range [IR], 10 to 1,048), whereas that in oral fluid specimens was 3 parasites/ml (IR, 0.41 to 92). However, there was no significant linear relationship between parasite loads assessed in the two biological samples ( ‫؍‬ 0.31 and P ‫؍‬ 0.06). VL diagnosis based on specific antibody detection and Leishmania DNA identification using oral fluid samples was equivalent in accuracy to that using blood and therefore is promising for clinical use.

The changing profile of cutaneous leishmaniasis agent in a central province of Iran

“…DNA-based molecular techniques have improved the identification of Leishmania parasites at the species level (Weirather et al, 2011;Galaï et al, 2011;Parhizkari et al, 2011;Ghasemian et al, 2011;Veland et al, 2012). The differential diagnosis of species and also suitable therapeutic strategies for the disease can be determined through precise protocols for identification of isolates from endemic areas where more than one Leishmania species may be present.…”

Evaluation of rK-39 Strip Test Using Urine for Diagnosis of Visceral Leishmaniasis in an Endemic Region of India

“…26,27 A few non-invasive sampling methods have been developed in VL diagnosis using human sputum, oral fluid, saliva, urine, and buccal swab samples with good sensitivity and specificity. [28][29][30][31] Advantages of the urine rK-39 ICT are that it is simple, rapid, non-invasive, and userfriendly, it has a reliable indicator, it is easy to collect, and it does not require equipment. Additionally, the results are unambiguous with high sensitivity and specificity.…”

Detection of Leishmania siamensis DNA in Saliva by Polymerase Chain Reaction

“…[18][19][20] Collection of saliva is noninvasive and convenient for field studies. We describe a PCR to amplify the internal transcribed spacer1 (ITS1) gene of L. siamensis from six infected patients and compare it with specimens collected from patients and different clinical presentations.…”