Generally apparent signs such as diarrhea and constipation are considered enough to know that a person has IBD or IBS, and doctors can recommend some treatment accordingly. However, if the problem is a rather infection and is not dying away with some initial treatments, doctors will need to carry out further tests to know the level of the problem and thus recommend the treatment.
The most common test in detecting IBS is test of blood sample of the patient. This test is essential if the patient is suffering from some other conditions such as ulcers, colitis. Sometimes, chances of infection are greater, if a person has moved to a new location, and the environment is rather unhealthy.
Another test commonly performed is the full blood count (FBC). This test is performed if the doctors suspect that a person might also be suffering from anaemia, which is associated with almost all gut disorders. Anaemia chances are greater if gut disorder is not just a disorder but a gut infection. The tests help the doctors to know if the person also has anaemia above the gut infection and can prescribe solutions accordingly.
Erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) is another test that is performed in the patients of gut disorder during the diagnostic process. The test is not as extensively used as are other two testing methods, but doctors do need this test if the patient's conditions does not improve through the initial treatment process and they are required to be admitted to a hospital.
Antibody testing is another test. However, this one is carried out for coeliac disease. The test is not performed if the person has a general gut disorder, including infection. Nevertheless, it is one of the ways to know if the person is suffering from a rather serious problem.
Although it is not required very often, doctors can carry out the detailed test of endoscopy, which involves examining of bowel through use of telescopic tools. This test is performed if the symptoms of IBS are rather unusual and doctors are unable to know the level of the problem through other testing methods.