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Jul 19Doctors on Manly Road

10:00am 10:10am 10:30am 10:40am 10:50am 11:30am 11:40am 11:50am

Jul 19Alpha Medical Clinic

8:00am 8:15am 8:30am 8:45am 9:00am 9:15am 9:30am 10:00am

Jul 19Joondanna Medical Centre

9:00am 9:15am 9:45am 10:15am 11:30am 11:45am 12:15pm 12:30pm

Jul 19Newington Medical

3:30pm 3:45pm 4:30pm

Jul 19Woodville Road Medical and Dental Centre

9:10am 9:20am 9:30am 9:40am 9:50am 10:00am 10:10am 10:20am

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Faecal Occult Blood Test

Faecal Occult Blood (FOB) is a simple bedside test which can also be performed in the laboratory. It uses a colour-change indicator to detect small (“occult”) amounts of blood in the stools (faeces).

How the Test is Performed

The Faecal Occult Blood (FOB) test can be performed in a laboratory, or as a “side-room” test in the hospital or doctor’s rooms. It involves placing a small amount of stool in contact with a small tablet, with a drop of water. If the tablet changes colour (usually to blue) it indicates a strong possibility of microscopic amounts of blood being present in the stool.

Medical Conditions and Symptoms

A Faecal Occult Blood (FOB) test may be requested by your doctor if there is a suspicion of bleeding from the gastrointestinal tract. Small amounts of blood loss that are not visible in the stools can be detected by this test. FOB is often performed in the setting of anaemia (low Haemoglobin or “blood count”), especially if this is due to iron deficiency, it may point to chronic (i.e., over a long period of time) blood loss from the stomach or bowel. A positive FOB test can be caused by any condition that causes bleeding from the stomach, small intestine, or colon, as well as swallowed blood, for example from a nosebleed (epistaxis). Typical examples include an ulcer in the stomach or duodenum, inflammation anywhere along the gastrointestinal tract, or even a tumour of the colon or rectum.

Test Results Explained

Faecal Occult Blood (FOB) may be reported as:

negative – no blood in the stool, normal
positive – blood present in the stool, due to a wide range of possible causes, or a false positive result (for example, due to eating red meat or certain raw fruits and vegetables in the 48 hours prior to the test).