Pathophysiology
1) diffuse inflammatory disease of large intestine (affects colon only, with some “backwash ileitis”) with exacerbations and remissions 2) rectum is almost always involved
Signs and Symptoms
1) chronic diarrhea 2) rectal bleeding (occasionally massive) 3) mucus in stool 4) tenesmus (rectal discomfort and pressure) 5) crampy abdominal pain 6) low grade fever 7) uveitis 8) arthritis (25%) 9) erythema nodosum 10) pyoderma gangrenosum 11) liver disease (3%)
Histology/Gross Pathology
1) essentially a disease of colon mucosa 2) early phase – mucosa is reddish, raw, and granular with pseudopolyps and crypt abscesses 3) progressive phase – atrophy of mucosa with loss of folds 4) advanced phase – shortened bowel, especially on the left
Associated Conditions
1) primary sclerosing cholangitis 2) hepatitis 3) carcinoma of bile ducts 4) thromboembolic events (6%) 5) ankylosing spondylitis (10%) 6) increased risk of colon cancer (200 times baseline) 7) autoimmune hepatitis 8) Turner’s syndrome
Inheritance/Epidemiology
1) occurs mostly in Western nations 2) most common in young adults 3) more typical in whites, Jews, and higher socioeconomic classes 4) 40% of cases occur in first-degree relatives 5) occurs equally in males and females
Treatment
1) first line drug – sulfasalazine (with folic acid supplementation) 2) second line drugs – azathioprine and 6-mercaptopurine 3) third-line drugs – methotrexate and cyclosporine A 4) for acute flare-ups – steroids (must be tapered) or bowel rest and parenteral nutrition 5) ileoproctectomy with anal anastomosis is commonly performed in long-standing disease because of cancer risk
Tips for USMLE
1) toxic megacolon (transverse colon > 6 cm with loss of haustral folds) is a life-threatening complication of ulcerative colitis 2) resection of affected bowel in ulcerative colitis relieves the associated arthritis (unlike in Crohn’s disease)
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