Improved detection of DNA Schistosoma haematobium from eggs extracted by bead beating in urine

<p>Diagnosis of Schistosoma haematobium relies primarily on microscopical analysis of urine. The method is time consuming and<br> requires some expertise. Genus-specific real-time PCRs have been developed, but we still observed low sensitivity. In the present<br> study, in order to achieve a more sensitive DNA detection of eggs of S. haematobium in urine samples, we wanted to develop a<br> novel protocol of DNA extraction using mechanic disruption of eggs by bead beating as supplementary step. We tested<br> Schistosoma spp. internal transcribed spacer 2 real-time PCR after both methods with and without bead beating. First, we<br> preliminary assessed the DNA detection after bead beating using dilution of 2, 10, 50, and 90 eggs/10 mL, and the Ct value<br> analysis showed significant improved DNA detection per each point of egg concentration using the novel supplementary step.<br> Twenty microscopy positive and five microscopy negative urine samples were used to validate the procedure. All urines came<br> from imported cases and admitted at center for tropical medicine, and were examined by microscopy. PCR results after novel<br> method with bead beating showed 100% to be positive for S. haematobium, compared with 85% positive by our standard<br> extraction procedure. Results confirmed mechanic disruption of eggs by bead beating before DNA extraction to be highly<br> effective method for the detection of S. haematobium DNA in urine.</p>