Prophylactic resection, uncomplicated diverticulitis, and recurrent diverticulitis.

The classifications of acute uncomplicated diverticulitis and complicated diverticulitis have served us well for many years. However, in recent years, we have noted the prevalence of variations of uncomplicated diverticulitis, which have not precisely fit under the classification of 'acute resolving uncomplicated diverticulitis', which manifests itself with the typical left lower quadrant pain, fever, diarrhea, elevated white blood count, and CT findings, such as stranding, and which resolves fairly promptly and completely on oral antibiotic therapy. For these other variations, we would suggest we use the term chronic diverticulitis, as a subset of uncomplicated diverticulitis, meaning there is no abscess, stricture, or fistula, but the episode does not respond to the usual antibiotic treatment, and there is a rebound symptomatology once the treatment has stopped, or there is continuing subliminal inflammation that continues, typically, for several weeks after the initial episode without complete resolution. This variation could also be termed 'smoldering' diverticulitis. A second variation of uncomplicated diverticulitis should be termed atypical diverticulitis, since this variant does not manifest all of the usual components of acute diverticulitis, particularly an absence of fever, and even white blood count elevation, and there may be a lack of diagnostic evidence of acute diverticulitis. This diagnosis must be compared with diarrhea-predominant irritable bowel syndrome, and it is sometimes very difficult to distinguish between these two entities. The character of the pain in irritable bowel syndrome is typically cramping intermittently, compared with the more constant pain in smoldering diverticulitis. In our study by Horgan, McConnell, Wolff and coworkers, 5% of 930 patients who underwent sigmoid resection fit into this category of atypical uncomplicated diverticulitis. These 47 patients all had diverticulosis, and 76% that had surgery had evidence of acute and chronic inflammation, and 15% had an unsuspected pericolonic abscess. There was no mortality and a low complication mortality rate (4.2%). Complete resolution of symptoms was achieved in 76.5 with 80% being pain free. Therefore, this is mostly a diagnosis of exclusion, and clinicians must be careful to perform a thorough workup and evaluation before proceeding to surgery with this as a diagnosis. Ischemic colitis is also in the differential diagnosis, and many patients who have diverticulitis, have irritable bowel syndrome as well, so caution must be used in predicting positive outcomes after surgery in these patients.