Diverticular disease of the colon: new perspectives in symptom development and treatment

Abstract

Diverticular disease of the colon is a common disease worldwide. Although the disease is asymptomatic in about 70-80 % of patients, it represents, at least in Western countries, one of the most important gastrointestinal diseases in terms of direct and indirect health costs. Pathogenesis of the disease is still unknown. However, it is the result of complex interactions between colonic structure, intestinal motility, diet and genetic factors. Whilst efficacious preventive strategies remain to be identified, fibre supplementation in the diet is recommended. Why symptoms develop is still unclear. Results of recent experimental studies on irritable bowel syndrome speculated that low grade inflammation of colonic mucosa, induced by changes in bacterial microflora, could affect the enteric nervous system, which is crucial for normal gut function, thus favouring symptom development. This hypothesis could be extrapolated also for diverticular disease, since bacterial overgrowth is present, at least in a subgroup of patients. These perspectives on symptom development are reviewed and new therapeutic approaches are hypothesized.

Figure 1

Diverticular disease: putative role of intestinal bacterial overgrowth in symptom development. Altered intestinal microflora could contribute to chronic low-grade inflammation (supported by both immunocytes and mast cells) which abnormally sensitised both intrinsic primary efferent and extrinsic primary afferent neurons. This condition could lead to neural and muscle dysfunction (i.e. altered intestinal motility and visceral sensitivity) and, finally, to symptom development.