Several problems of the intestines can cause pain but few of these produce constant or recurrent chronic pelvic pain without significant other associated findings. The normal function of the intestines involves an organized and orderly movement from the stomach along the entire pathway of the small intestine every 2 hours or so. A meal will disrupt this movement cycle to produce a pattern of intermittent contractions, which is largely determined by the type and amount of nutrients that have been ingested. Any disorder of the intestines that disrupts the usual movement and processing of food will cause pain. For the pain to be intermittent the functional disorder must be incomplete since a complete disruption would result in an acute and severe problem.
Chronic intermittent bowel obstruction may disrupt the orderly movement of the bowel contents and produce intermittent pain. The causes of bowel obstruction may include external bowel adhesions or scar tissue within the pelvis, herniation or protrusion of a loop of bowel through an opening (canal) in the wall of the abdomen or a dense collection of adhesions, infectious inflammatory lesions of the bowel possibly including diverticulitis or infective colitis, noninfectious inflammatory bowel lesions such as Crohn's disease or ulcerative colitis, or external tumors pressing on and compressing the bowel. Intermittent bowel obstruction may cause sharp one sided (unilateral) or two sided (bilateral) pelvic pain, bloating, and nausea. Diagnosis is difficult between attacks so testing should be coordinated with a Gastroenterologist and might include xrays, a barium enema with small bowel follow through xrays, or colonoscopy.
Inflammatory bowel diseases include Crohn's disease and ulcerative colitis. Crohn's disease is an inflammatory disorder of the intestines that involves the full thickness of the bowel wall in the affected sections and Crohn's disease may occur anywhere along the pathway from the mouth to the anus, but most often involves the terminal portion of the small intestine that is called the ileum. The most common symptoms of Crohn's disease are lower abdominal pain (especially on the right side), diarrhea, rectal bleeding and possibly weight loss. Ulcerative colitis is a different inflammatory disorder of the intestines that specifically targets the large intestine or colon and results in ulcerations that only involve the innermost lining (mucosa) of the bowel wall. The most common symptoms of ulcerative colitis are diarrhea mixed with blood or mucus, lower abdominal pain and weight loss. When either of these diseases is considered it is prudent to obtain a gastrointestinal consultation. Treatment of symptomatic ulcerative colitis might include surgery on the affected colon while surgery for Crohn's disease is limited to the treatment of complications (such as intestinal obstruction, fistulas, severe hemorrhage). Medical management with steroids, immunosuppressive therapies, and aminosalicylates (like sulfalazine) may be tried for either ulcerative colitis or Crohn's disease.
Constipation is bowel condition in which a person experiences very hard stool that is difficult to eliminate and can result in significant pain. Some try to define constipation by either a frequency of bowel movements less than 3 times a week, decreased stool bulk or size, or need for significant straining for the passage of stool. The main causes of constipation include insufficient dietary fiber, dehydration, as a side effect of certain medications, decreased bowel transit time due to hypothyroidism or hypokalemia, constrictions in the bowel such as strictures or diverticula, or irritable bowel syndrome. The primary treatments are increased dietary fiber and an increased intake of fluids (especially water). If laxitives are used, the hydrating or bulk-forming laxatives are generally preferred over the use of stimulatory laxitives.