The Three Main Variants

Let's now look at the variants of IBS. For research purposes some investigators have restricted the term IBS to describe the Spastic Colon Syndrome (e.g. Rome II Classification 1999). There is a feeling that one should refer to two predominant forms, namely:

- diarrhoea predominant IBS
- constipation predominant

IBS Our recent research has highlighted the existence of a diarrhoea predominant form of Spastic Colon Syndrome in which the patient experiences:

- abdominal pain
- visible abdominal distension (bloating)
- bowel frequency, particularly in association with pain**
- pain relieved by bowel action
- rectal passage of mucus
- sensation of incomplete evacuation

We acknowledge that there are patients with the Spastic Colon Syndrome variant in whom constipation predominates. While we have not yet completed our motility studies we are confident of the existence of a constipation predominant Spastic Colon Syndrome in which patients experience:

- abdominal pain
- visible abdominal distension (bloating)
- constipation, particularly in association with pain**
- pain relieved by bowel action
- rectal passage of mucus
- sensation of incomplete evacuation

** Note the differences in background bowel habit. We have previously restricted ourselves to the simple classification 'Spastic Colon Syndrome' as we, like others, are aware that patients often switch from one to the other, constipation or diarrhoea predominant form and vice versa, a phenomenon which others have referred to as 'alternating IBS'.

Bearing that phenomenon in mind, we have described three major variants of IBS, namely Spastic Colon Syndrome, Functional Diarrhoea and Primary Motility Disorder of the Midgut (Pain, Gas, Bloat Syndrome), independently described by the Mayo Clinic Group in America headed by, Professor Michael Camilleri

In practice, we find that there is a degree of cross over between the three variants and some patients might complain of more than one symptom of any one of the variants at any one time.
Outline of Variants: their Main Symptoms and Treatments:

The pages linked below describe the symptoms of each of the three variants and give information about accepted treatments.
     

IBS ResearchUpdate.org Current Page:
Main Variants Of IBS