Bowel 1

Inflammatory Bowel Disease Background Inflammatory bowel disease (IBD) commonly refers to: ulcerative colitis (UC) and Crohn disease (CD) which are chronic inflammatory disease of the GI tract of unknown etiology

Inflammatory Bowel Disease Background Crohn disease is also referred to as: regional enteritis terminal ileitis or granulomatous ileocolitis

Inflammatory Bowel Disease Pathophysiology Increasing evidence suggests that, at least in CD, there is a defect in the function of the intestinal immune system As a consequence:▼ ►there is a breakdown of the defense barrier of the gut, which, in turn, results in ► exposure of the mucosa to microorganisms or their products

Inflammatory Bowel Disease Pathophysiology In UC, inflammation always begins in the rectum, extends proximally a certain distance, and then abruptly stops A clear demarcation exists between involved and uninvolved mucosa

Inflammatory Bowel Disease Pathophysiology The rectum is always involved in UC, and no "skip areas" are present UC primarily involves ▼ the mucosa and the submucosa with formation of: crypt abscesses and mucosal ulceration

Inflammatory Bowel Disease Illustration: UC without skip areas

UC The mucosa typically appears granular and friable

Inflammatory Bowel Disease Pathophysiology In severe cases (UC) ►1) In more severe cases, pseudopolyps form, consisting of areas of hyperplastic growth with swollen mucosa 2) Inflammation and necrosis can extend below the lamina propria to involve the submucosa and the circular and longitudinal muscles, although this is unusual

Inflammatory Bowel Disease

• Illustration: pseudopolyps

Inflammatory Bowel Disease Pathophysiology UC remains confined to the rectum in approximately 25% of cases In the remainder of cases, UC spreads proximally and contiguously Pancolitis occurs in 10% of patients

Inflammatory Bowel Disease Pathophysiology UC The small intestine is never involved, except when the distal terminal ileum is inflamed in a superficial manner, referred to as backwash ileitis

Inflammatory Bowel Disease Pathophysiology CD The most important pathologic feature is involvement of all layers of the bowel, not just the mucosa and the submucosa, as is characteristic of UC

Inflammatory Bowel Disease Pathophysiology CD is discontinuous, with skip areas interspersed between one or more involved areas

Inflammatory Bowel Disease CD with skip areas (large intestine)

CD

Inflammatory Bowel Disease

Pathophysiology The 3 major patterns of involvement in CD are: (1) disease in the ileum and cecum, occurring in 40% of patients (2) disease confined to the small intestine, occurring in 30% of patients and (3) disease confined to the colon, occurring in 25% of patients

Inflammatory Bowel Disease

Pathophysiology CD causes 3 patterns of involvement: (1) inflammatory disease (2) strictures and (3) fistulas

Inflammatory Bowel Disease

Pathophysiology Extraintestinal manifestations of include: iritis episcleritis arthritis and skin involvement as well as pericholangitis sclerosing cholangitis

IBD

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Inflammatory Bowel Disease Mortality/Morbidity The most common causes of death in IBD are: peritonitis with sepsis malignancy thromboembolic disease and complications of surgery

Inflammatory Bowel Disease Mortality/Morbidity Toxic megacolon, one of the most dreaded complications of UC, can lead to: perforation sepsis shock and death

Inflammatory Bowel Disease • Illustration: toxic mega colon

Inflammatory Bowel Disease Mortality/Morbidity Malnutrition and chronic anemia are observed in long-standing CD Children with CD or UC can exhibit growth retardation

Inflammatory Bowel Disease Race Incidence among whites is approximately 4 times that of other races Sex Incidence is slightly greater in females than in males Age Incidence peaks in the second and third decades of life

Inflammatory Bowel Disease CLINICAL History Patients with ulcerative colitis (UC) most commonly present with bloody diarrhea

Whereas patients with Crohn disease (CD) usually present with nonbloody diarrhea

Inflammatory Bowel Disease CLINICAL History Abdominal pain and cramping fever and weight loss occur in more severe cases

Inflammatory Bowel Disease CLINICAL History Remember The greater the extent of colon involvement, the more likely the patient is to have diarrhea

Rectal urgency or tenesmus reflects reduced compliance of the inflamed rectum

CLINICAL History As the degree of inflammation increases, systemic symptoms develop, including: low-grade fever malaise nausea vomiting sweats and arthralgias

Inflammatory Bowel Disease CLINICAL History Fever Dehydration and abdominal tenderness ►develop in severe UC, reflecting progressive inflammation into deeper layers of the colon

Inflammatory Bowel Disease CLINICAL History

The presentation of CD is generally more insidious than that of UC, with ongoing: abdominal pain anorexia diarrhea weight loss and fatigue

Inflammatory Bowel Disease CLINICAL History Grossly bloody stools, while typical of UC, are less common in CD One half of patients with CD present with perianal disease: Example: Fistulas abscesses

Inflammatory Bowel Disease CLINICAL History ► Occasionally, acute right lower quadrant pain and fever may be noted, mimicking appendicitis ► Commonly, the diagnosis is established only after several years of: recurrent abdominal pain fever, and diarrhea