Chapter 39 : Evaluation of a Rapid Immunochromatographic Assay for Detection of Legionella pneuntophila in Urine

Abstract:

Current methodologies for the diagnosis of legionellosis are time-consuming and labor-intensive, which dissuades many doctors from ordering the tests. To make the urinary rapid diagnostic, antibody was raised to the carbohydrate portion of Legionella serogroup 1. The antibody was immobilized on nitrocellulose and conjugated to colloidal gold particles to produce an immunochromatographic test (ICT). To evaluate the test, a retrospective study was performed in which 300 frozen archive urine samples were thawed and evaluated using the ICT device. Results were compared with culture diagnosis. A prospective study was then performed in which 93 urine samples were collected from symptomatic patients reporting to the hospital with lower respiratory symptoms or sepsis. The purpose of this study was to evaluate the test with fresh urine samples. These patients were evaluated by culture and the ICT. In these samples, the specificity of the test was 100%. No samples were positive either by culture or ICT for Legionella pneumophila. Since the test can be performed rapidly with accurate results, the test is leading to more patients being properly diagnosed and treated accordingly.