- Ulcerative colitis (UC), one of the two inflammatory bowel disease, is a chronic disease characterized by diffuse mucosal inflammatory changes limited to the colon.
- Most cases involve the rectum or terminal colon and may extend proximally in a continuous fashion involving part or the entire large intestine (pan-ulcerative colitis) (1).
- Frequently manifested by recurrent episodes of bloody and mucoid diarrhea often associated with abdominal pain, rectal urgency, stool incontinence, fever, and weight loss
- Clinical course includes exacerbations and spontaneous or treatment-induced remissions.
- Colonic involvement is universal and may be accompanied by other systemic manifestations including large joint arthritis, ocular inflammation, skin lesions, biliary disease, liver disease, thromboembolic disease, and pulmonary complications.
Because UC is commonly diagnosed in young people and has relatively low mortality, prevalence may continue to rise:
- North America: 249/100,000 persons
- Europe: 505/100,000 persons
Etiology and Pathophysiology
- Idiopathic inflammatory disorder; hypothesized to result from autoimmune dysfunction in response to colonic microbiome, genetic predisposition, and distinct risk factors
- Almost universally associated with inflammation of the terminal colon. >95% of patients have rectal involvement, 50% have disease limited to the rectum and sigmoid, and 20% have pancolitis. The absence of rectal involvement has been noted in <5% of adult patients and in up to 1/3 of pediatric patients.
- Genetic factors contribute to IBD susceptibility.
- Several genetic syndromes have been associated with IBD (Turner syndrome, Hermansky-Pudlak syndrome, and glycogen storage disease type 1b).
- Incidence rates were highest among persons 20 to 40 years old.
- Incidence rates of IBD are higher in white and Jewish people.
- Increasing incidence of UC in developing nations suggest that UC may be influenced by environmental factors.
- Having multiple family members with UC (2)
- Theorized risk factors include disruption of the colonic microbiome by enteric infection, dietary factors (Western diet in particular), antibiotic use, lack of breastfeeding in infant, obesity, and NSAID use.
Smoking may lower the risk of UC.
- Patient should be advised to conceive during remission if planning a pregnancy.
- Given the higher risk of thromboembolism in patients with UC, an estrogen-free contraceptive is preferred (2).
- Variable disease course in pregnancy seems to mirror disease state at conception; 3 to 6 months of remission before conceiving decreases the risks of an exacerbation during pregnancy (2).
- There is increased risk of preterm delivery and small for gestational age in women with active disease.
- Incidence rate of offspring from a UC mother of having UC is 3.7 (absolute rate of 1.6%).
- Ideally, pregnant women should be monitored by both gastroenterologist and maternal–fetal medicine specialist (2).
- Breastfeeding may protect against pediatric IBD.
- Pancolonic involvement is more likely at onset with shorter time from diagnosis to colectomy (median 11 years) than adults.
Commonly Associated Conditions
- Arthritis: large joint, sacroiliitis, ankylosing spondylitis (common)
- Aphthous ulcers (common)
- Erythema nodosum (common)
- Osteoporosis (common)
- Fatty liver (common)
- Episcleritis and uveitis (rare)
- Autoimmune liver disease (rare)
- Liver cirrhosis (rare)
- Primary sclerosing cholangitis (rare)
- Bile duct carcinoma (rare)
- Thromboembolic disease (rare)
- Pyoderma gangrenosum (rare)
- Colon cancer (rare)
- Anemia (rare)
- Pulmonary diseases (very rare)
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