First some tests to rule out anything sinister
The main symptoms of IBS (abdominal pain and constipation and/or diarrhoea) are common to several other disorders as well. So, when you present to your doctor with gut issues, expect to be sent for some gut health tests to make sure that there is no anatomical reason for your bowel problems and rule out certain conditions, particularly if your doctor identifies ‘red flags’ such as:
· unintentional and unexplained weight loss
· rectal bleeding
· a family history of bowel or ovarian cancer
· a change in bowel habit to looser and/or more frequent stools persisting for more than six weeks in a person aged over 60 years
You will have blood tests for levels of inflammation and to rule out other gut conditions, such as inflammatory bowel diseases (IBDs), coeliac disease, cancer. Sometimes it may be necessary for a colonoscopy to check the inside of your bowel for anything abnormal. (Although this is unpleasant, it is usually painless).
The test results are negative - Time to Determine if it’s IBS
If the results across a range of diagnostic exams and tests are negative – that is, your digestive tract appears perfectly normal, then your doctor (or gastroenterologist) will use the Rome IV diagnostic criteria to determine if you are experiencing IBS.
The Rome IV criteria
The Rome IV criteria state that for a diagnosis of IBS to be given, certain factors need to be met. These are:
Recurrent abdominal pain, on average at least 1 day/week in the last 3 months, associated with two or more of the following criteria:
1. Related to defecation
2. Associated with a change in frequency of stool
3. Associated with a change in form (appearance) of stool
These criteria must be fulfilled for the last 3 months with symptom onset at least 6 months prior to diagnosis.
[Source: The Rome Foundation]
Other symptoms such as lethargy, nausea, backache, and bladder symptoms are common in people with IBS and the presence of these may help your doctor in making his/her diagnosis of IBS.
You will be assigned an IBS sub-category
Once you have your IBS diagnosis, your doctor (gastroenterologist) will place you into one of three IBS categories based on your symptoms:
· IBS-C is accompanied by constipation.
· IBS-D is accompanied by diarrhoea.
· IBS-M includes both diarrhoea and constipation.
This categorisation will inform the treatment plan your doctor puts you on.