The presence blood in the stool is an abnormal con- dition indicative of disease states of the gastroin- testinal system, and multiple studies have shown a strong correlation between collorectal cancer (CRC) and rectal bleeding.
The use of rapid tests to verify the presence of blood in stool is very important as blood may not always be visible to the naked eye.
There are two common rapid methods for the de- tection of hidden blood in stool. The first uses the chemical Guaiac to produce color in the presence of heme in blood, called Guaiac fecal occult blood test (gFOBT).
The second is a chromatographic immunoassay that uses spesific antibodies to detect blood in stool, this method is called Immunochemical fecal occult blood test (iFOBT) or Faecal immunochemi- cal testing (FIT).