What is Colonic Diverticular?
Colonic diverticulosis is one of the most widespread diseases of developed Western countries. An increase in its prevalence has been reported, and a low-fiber diet has been shown to be the major cause among other predisposing factors. In the United States, studies have confirmed the findings of diverticula in about 5 to 10% of the population by age 50, 30% of those aged over 50, in 50% of those over 70 and in 66% of people over 85 years of age. It also affects a considerably significant proportion of younger adults. Diverticulosis frequently shows no symptoms; however, 10% to a quarter of patients with diverticulosis will eventually progress to diverticulitis and suffer with symptoms ranging from minor complaints to life-threatening conditions. Patients with severe complications may require hospital admission and treatment depending on the phase of the disease.
Most individuals do not show symptoms of the disease, so the prevalence of diverticulitis is difficult to measure. A comparison of the earliest and most recent autopsy and studies of barium enema (or x-ray of the large intestine) indicate that the occurrence is quickly increasing globally. Results of barium examinations and necropsy series are examined, and the findings may be misleading for determining the precise actual prevalence rate, since barium studies tend to mistake diverticulitis in patients who have been referred for gastrointestinal (GI) symptoms, and necropsy series may either overrate the occurrence of diverticula in older age groups or overlook the presence of small diverticula in younger populations. It is not known if these results are due to an increased number of older individuals in the population, or if more people are being tested, or if there is an actual rise in the prevalence of the disease.
Generally, colonic diverticulosis is an acquired disease, building up as mucosal and submucosal herniations through the circular muscle layer at vulnerable and frail points of the colonic wall. Serosa is being covered by diverticula which tends to develop at four well-defined points around the circumference of the colon where the vasa recta penetrate the muscular layer. These vessels penetrates the colonic wall on each side of the mesenteric taenia and on the mesenteric border of the two antimesenteric taeniae. Diverticula do not develop in the rectum, presumably because of the coalescence of the taenia with the longitudinal muscle layer that marks the junction between the sigmoid colon and the rectum. Mychosis is a set of diagnosis which consists of thickening of the muscular layer, shortening of the taeniae, and luminal narrowing. Mychosis is to be found in most patients with sigmoid diverticula.
The mechanical features of the colonic wall deteriorate with increasing age. Combined barostat-manometry studies of the entire colon demonstrated that compliance is lowest in the sigmoid and descending colon and greatest in the transverse and ascending colon. This disparity in mechanical properties between the right and left sides might partly account for the left-sided predominance of diverticulosis.