西安交通大学医学院消化系统疾病课件 Ulcerative Colitis.pptVIP

Ulcerative Colitis Qiao Wen Department of Gastroenterology Definition Chronic nonspecial inflammatory diseases of the rectum and colon of unknown etiology. The lesion is limited in mucosa and sub- mucosa of large intestine. Clinical features are diarrhea, mucus and bloody purulent stool, abdominal pain. Incidence The incidence is 70-150 cases per 100,000 individuals. Incidence among whites is approximately 4 times that of other races. 3. Incidence is slightly greater in females than in males. Pathophysiology Inflammation begins in the rectum, extends proximally a certain distance. 2. A clear demarcation exists between involved and uninvolved mucosa, and no skip areas are present. Pathophysiology 3. Primarily involves the mucosa and the submucosa. 4. Formation of crypt abscesses and mucosal ulceration. 5. The mucosa typically appears granular and friable. 6. Pseudopolyps form, in more severe cases. Pathogenesis 1. The etiology of UC is unknown. 2. Environmental, infectious, genetic, autoimmune, and host factors have been suspected.Interactions among these factors may be more important. . Pathogenesis 3. Inflammatory mediators: Interleukin-1, Tumor necrosis factor alpha (TNF-alpha). 4. The most important risk factor for developing UC is a positive family history. Clinical manifestations Symptoms Bloody diarrhea Abdominal pain and cramping occur in more severe cases. Rectal urgency or tenesmus reflects reduced compliance of the inflamed rectum. Systemic symptoms, including low-grade fever, malaise, nausea, vomiting, sweats, and arthralgias. dehydration. Symptoms Recurrences may occur emotional stress, infections or other acute illnesses, pregnancy, dietary indiscretions, use of cathartics or antibiotics, withdrawal of anti-inflammatory or steroid medications. Symptoms In 10-20% of cases, patients present with extraintestinal manifestations, including arthritis,