Comparison of diagnostic sensitivities of three assays (Bartels enzyme immunoassay [EIA], Biotest EIA, and Binax NOW immunochromatographic test) for detection of Legionella pneumophila serogroup 1 antigen in urine.

The Bartels enzyme immunoassay (EIA), Biotest EIA, and Binax NOW immunochromatographic test (ICT) urinary antigen kits for the detection of Legionella pneumophila serogroup 1 were compared using 178 frozen urine samples. When nonconcentrated urine samples were used, the sensitivity levels of both enzyme EIAs were significantly higher than the sensitivity level of the ICT (Bartels EIA, 71.3%; Biotest EIA, 65.1%; Binax NOW ICT, 37% [P < 0.001]). After concentration of the urine samples, no significant differences in sensitivity were found among the three tests.