Faecal Occult Blood Test
Faecal Occult Blood Testing – what is FOBT
A test for fecal occult blood looks for blood in your stool. It can be a sign of a problem in your digestive system, such as a growth, or polyp, or cancer in the colon or rectum. This was the original test used in bowel cancer screening and is still in use in some areas. It is slowly being replaced by the Faecal Immunochemical Test “FIT”, which as seen as being more accurate and simpler to perform.
With the Fecal Occult Blood stool test kit, you collect small samples of your poo and wipe them on a special card. Samples are taken over three separate days.
How is the faecal occult blood test done?
The faecal occult blood test was commonly used in bowel cancer screening it is generally being replaced by the FIT test but is still being used in some areas.
A small stick / scraper is normally provided with the collection kit and in this stool test you obtain a sample by using the stick. A HyStool bag is best used to collect a stool then simply use the stick to scrape a small piece off and smear it on a window within the collection card. The remaining stool and HyStool bag can then be safely flushed away.
In the The faecal occult blood test two or three samples are required and these are collected on different days. This is because a bleeding disorder of the gut (intestine) may only bleed now and then. So, not every sample may contain blood. A series of two or three samples done on several days may be more accurate in detecting a bleeding gut disorder.
When the samples are submitted to a laboratory a chemical is added to the samples on the card. If there is a change in colour after adding the chemical, it indicates that some blood is present.
A doctor may do this test in the GP surgery, or send a sample to the laboratory for testing. Also, if required, there are test kits that you can get at pharmacies, which enable you to do the test at home. Some people are issued with test kits to do testing at home.
There are some foods and medications which may affect the results of FOB tests, making it appear there was blood present when there wasn’t. However, this is quite unusual and generally no dietary advice is now given when doing an FOB test.
