Diagnosis of mediterranean visceral leishmaniasis by detection of leishmania antibodies and leishmania DNA in oral fluid samples collected using an Oracol device.

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 (ρ = 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 (ρ = 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.

Genetic identification of intestinal microsporidia species in immunocompromised patients in Tunisia.

Stool samples from 86 immunocompromised patients (51 human immunodeficiency virus (HIV)-infected patients and 35 patients with haematologic malignancies) were systematically screened for intestinal microspordiosis by microscopic examination and polymerase chain reaction (PCR) using universal primer V1/PMP2. Nine samples (10.5%) showed amplification with the predictive size of fragment (6 from HIV-infected patients and 3 from patients with myeloma). Only 5 out of them (all HIV-infected patients) were revealed positive by microscopy. By means of amplicons fragment size, species-specific primers (V1/EB450, V1/IS500) and sequencing, 3 microsporidia species were for the first time identified in Tunisia: Enterocytozoon bieneusi (3 isolates), Encephelitozoon intestinalis (2 isolates), and Encephalitozoon hellem (1 isolate). Systematic use of such sensitive and discriminative molecular tools will contribute to determining the true prevalence of microsporidiosis in Tunisia and to better management of infected immunocompromised subjects.