Findings
There are diverticula and thickening of the walls of the sigmoid colon compatible with uncomplicated diverticulitis. Notice the absence of surrounding fat stranding.

Discussion
CT stages diverticulitis from Stage 0 through Stage IV depending on surrounding involvement and severity. Stage 0 shows only minor local colonic wall involvement and may be treated conservatively with antibiotics. The other stages usually necessitate surgical intervention. Stages I and II show contiguous spread of inflammation outside of the colon. Stages III and IV show peritoneal involvement with distant abscesses, ascites, through to frank peritonitis.


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