Irritable Bowel Syndrome
Irritable bowel syndrome (IBS, or spastic colon) is a symptom-based diagnosis characterized by chronic abdominal pain, discomfort, bloating, and alteration of bowel habits. Irritable bowel syndrome (IBS) is a very prevalent and high incident disease. As the great majority of functional diseases, it is female predominant and leads to serious damage to the quality of life.
The Irritable Bowel Syndrome is a common functional disorder probably affecting 10-15% of the population in developed countries, being 2-3-fold more common in females.
The Rome III criteria should be used to characterize the disease: recurrent abdominal pain and/or discomfort for at least 3 days a month in the last 3 months associated with 2 or more of the following: improvement with defecation and/or altered bowel movement frequency and/or altered stool form.
1. Constipation-predominant IBS (IBS-C): hardened, dry or lumpy stools (coprolith) in ≥ 25% and soft or pasty stool in <25% of evacuations;
2. Diarrhea-predominant IBS (IBS-D): loose or pasty stool in ≥ 25% and hardened, dry or lumpy stools (coprolith) in <25% of evacuations;
3. Mixed IBS (IBS-M): hardened stools in ≥ 25% and loose or soft stools in ≥ 25%;
4. Undetermined IBS: Insufficient abnormality in stool consistency to be allocated in one of the above subtypes.
The physiopathology of Irritable Bowel Syndrome is complex, involving several aspects such as altered processing of visceral pain through altered processes in peripheral afferent pathways, cortical pain processing and descending control of pain perception, visceral nociception, autonomic dysfunction and even genetic mechanisms, which may also vary from individual to individual.