Abstract
For the OC-Hemodia (quantification method using an autoanalyzer) of the LA method that is most commonly used among various types of reagents for immunological occult blood examination in colorectal cancer screening in Japan, a new autoanalyzer and a special sample collection container were recently developed. We measured the hemoglobin detection sensitivity of this new measurement system using artificial feces. When the cut-off value recommended by the manufacturer (100ng/ml) was used, the hemoglobin detection sensitivity limit was 25-30μgHb/g artificial feces. When hemoglobin detection sensitivity was evaluated with a reduction in the cut-off value from the recommended value, cut-off values to 30ng/ml were considered to be practical. In this cut-off value range, the hemoglobin detection sensitivity limit was 7.5-10μgHb/g artificial feces.
On the other hand, the hemoglobin detection sensitivity of Immudia-HemSp (qualitative method by visual observation) of the RPHA method that is also widely used in colorectal cancer screening was also measured using artificial feces. Using the cut-off value according to the manual, the hemoglobin detection sensitivity limit was 15-30μgHb/g artificial feces.
The hemoglobin detection sensitivity of the LA method using this new measurement system became higher than that of the RPHA method by reducing the cut-off value.