Phenolphthalein Method as a Simple and Low Cost Test for Detection of Fecal Occult Blood

Abstract

Background: Colorectal cancer is one of the main causes of cancer related death worldwide. Different investigation showed that screening with fecal occult blood is able to reduce incidence of colorectal cancer in a given area. To provide a simple and cost effective test for screening of colorectal cancer in this work sensitivity of phenolphthalein method in detection of occult blood has been investigated. Methods: In this descriptive study alcohol pyramidon and phenolphthalein methods were used to estimate the minimum amount of human occult blood which can be detected in distilled water and fecal samples. Then 100 fecal samples were examined by the two tests. Results: Alcohol pyramidon method detected minimum amount of 0.125 µL blood in 1 ml distilled water while phenolphthalein methods detected minimum amount of 0.0312 µL blood in 1 mL distilled water. In another experiment Alcohol pyramidon method detected minimum amount of 1 µL blood in 1 mL fecal sample while phenolphthalein methods detected minimum amount of 0.25 µL blood in about 1 mL fecal sample. Phenolphthalein method provided more positive results when 100 fecal samples were tested. Conclusion: phenolphthalein method is a sensitive, simple and economy test for colorectal cancer screening which can be used both in labs and at home.