Classification

The different subtypes of Crohn’s disease are:
§  Crohn’s colitis is inflammation that is confined to the colon. Abdominal pain and bloody diarrhea are the common symptoms. Anal fistulae and peri-rectal abscesses also can occur.
§  Crohn’s enteritis refers to inflammation confined to the small intestine (the first part, called the jejunum or the second part, called the ileum). Involvement of the ileum alone is referred to as Crohn’s ileitis. Abdominal pain and diarrhea are the common symptoms. Obstruction of the small intestine also can occur.
§  Crohn’s terminal ileitis is inflammation that affects only the very end of the small intestine (terminal ileum), the part of the small intestine closest to the colon. Abdominal pain and diarrhea are the common symptoms. Small intestinal obstruction also can occur.
§  Crohn’s entero-colitis and ileo-colitis are terms to describe inflammation that involve both the small intestine and the colon. Bloody diarrhea and abdominal pain are the common symptoms. Small intestinal obstruction also can occur.

Crohn’s terminal ileitis and ileo-colitis are the most common types of Crohn’s disease.
Crohn’s disease may also be categorized by the behavior of disease as it progresses.
§  Stricturing – causes narrowing of the bowel that may lead to bowel obstruction or changes in the caliber of the feces
§  Penetrating – creates abnormal passageways (fistulae) between the bowel and other structures, such as the skin
§  Inflammatory – causes inflammation without causing strictures or fistulae

Signs and symptoms

The most common symptoms in Crohn’s disease are those related to the inflammatory damage to the digestive tract.
§  Diarrhea – Waxes and wanes; stool may contain mucus, blood, or pus
§  Pain in the abdomen – Crampy or steady; in the right lower part of the abdomen or around the belly button; often relieved temporarily by having a bowel movement
§  Bloating after eating – Less common, usually seen in cases of bowel obstruction
§  Constipation – Usually seen in cases of bowel obstruction
§  Pain or bleeding with bowel movement
§  Infection of the urinary tract or vagina – Suggests a fistula from the intestinal tract

General symptoms occur in some but not all cases.



§  Low-grade fevers
§  Weight loss
§  Fatigue

Other symptoms of Crohn’s disease may be attributable to related medical conditions affecting the skin, joints, mouth, eyes, liver, and bile ducts.
Gastrointestinal
Many people with Crohn’s disease have symptoms for years prior to the diagnosis. The usual onset is between 15 and 30 years of age, but can occur at any age. Because of the ‘patchy’ nature of the gastrointestinal disease and the depth of tissue involvement, initial symptoms can be more subtle than those of ulcerative colitis. People with Crohn’s disease experience chronic recurring periods of flare-ups and remission.
Abdominal pain may be the initial symptom of Crohn’s disease. It is often accompanied by diarrhea, especially in those who have had surgery. The diarrhea may or may not be bloody. The nature of the diarrhea in Crohn’s disease depends on the part of the small intestine or colon involved. Ileitis typically results in large-volume, watery feces. Colitis may result in a smaller volume of feces of higher frequency. Fecal consistency may range from solid to watery. In severe cases, an individual may have more than 20 bowel movements per day and may need to awaken at night to defecate. Visible bleeding in the feces is less common in Crohn’s disease than in ulcerative colitis, but may be seen in the setting of Crohn’s colitis. Bloody bowel movements are typically intermittent, and may be bright or dark red in color. In the setting of severe Crohn’s colitis, bleeding may be copious. Flatulence and bloating may also add to the intestinal discomfort.
Symptoms caused by intestinal stenosis are also common in Crohn’s disease. Abdominal pain is often most severe in areas of the bowel with stenoses. In the setting of severe stenosis, vomiting and nausea may indicate the beginnings of small bowel obstruction. Although the association is greater in the context of ulcerative colitis, Crohn’s disease may also be associated with primary sclerosing cholangitis, a type of inflammation of the bile ducts, but it is more commonly associated with Ulcerative Colitis.
Perianal discomfort may also be prominent in Crohn’s disease. Itchiness or pain around the anus may be suggestive of inflammation, fistulization or abscess around the anal area or anal fissure. Fecal incontinence may accompany perianal Crohn’s disease. At the opposite end of the gastrointestinal tract, the mouth may be affected by non-healing sores (aphthous ulcers). Rarely, the esophagus, and stomach may be involved in Crohn’s disease. These can cause symptoms including difficulty swallowing (dysphagia), upper abdominal pain, and vomiting.