Method for differentiating the source of occult gastrointestinal bleeding

摘要

The presence of fecal occult blood in a stool sample is detected by mixing a liquid stool sample with an acidic liquid, such as a phosphate/citrate buffer, to precipitate hematin from the solution. The precipitated hematin is separated and the presence or absence of hemoglobin is determined by exposing the solution to a peroxidase diagnostic assay. A positive response indicates the presence of blood originating in the lower gastrointestinal tract, a leading indicator of lower GI cancer.