immune system indicators in ulcerative colitis

43, 44 Certain ulcerative colitis risk factors that are significant in developed countries might not have the same effect in developing Asian or Middle Eastern populations. 36– 42 Breastfeeding appears to decrease the risk of ulcerative colitis, while urban living can increase the risk. 34, 35 Drugs, such as oral contraceptives, hormone replacement therapy, and non-steroidal anti-inflammatory drugs, have all been associated with an increased risk of ulcerative colitis, while antibiotic exposure has not. 33 Patients newly diagnosed with ulcerative colitis are more likely than matched controls to have a history of gastroenteritis. 24, 29– 32 Appendectomy appears to confer a protective effect against developing ulcerative colitis, especially when done for acute appendicitis in young patients. Former cigarette smoking is one of the strongest risk factors associated with ulcerative colitis (odds ratio 1.79, 95% CI 1.37–2.34), while active smokers are less likely to develop ulcerative colitis compared with former and non-smokers (OR 0.58, 95% CI 0.45–0.75) and have a milder disease course. The rising incidence of ulcerative colitis worldwide suggests the importance of environmental factors in its development. 27, 28 However, genetics only explain 7.5% of disease variance, have little predictive capacity for phenotype, and currently are of limited clinical use. 26, 27 Examples of loci associated with increased ulcerative colitis susceptibility include human leukocyte antigen and genes associated with barrier function, such as HNF4A and CDH1. 24, 25 Genome-wide association studies have identified 200 risk loci for inflammatory bowel disease to date, with most genes contributing to both ulcerative colitis and Crohn’s disease phenotypes. 22, 23 Jewish populations have higher rates of ulcerative colitis than other ethnicities. 18– 21Ĩ–14% of patients with ulcerative colitis have a family history of inflammatory bowel disease and first-degree relatives have four times the risk of developing the disease. 15– 17 Less data is available from developing countries however, recognition of ulcerative colitis is increasing in Asia, the Middle East, and South America. 14 The risk of developing ulcerative colitis in children of migrants from low-incidence to high-incidence countries is similar to non-immigrants. 7, 10, 12, 13 Within Europe, there appears to be differences in ulcerative colitis incidence, with countries located in the western and northern regions having higher incidences than eastern countries. 10 The highest incidences of ulcerative colitis have been reported in northern Europe (24.3 per 100 000), Canada (19.2 per 100 000), and Australia (17.4 per 100 000). 7, 9 The incidence and prevalence of ulcerative colitis have been increasing over time worldwide ( figure 1). 6– 8 The peak age of disease onset is between ages 30 years and 40 years.

No sex predominance exists in ulcerative colitis. The therapeutic armamentarium for ulcerative colitis is expanding, and the number of drugs with new targets will rapidly increase in coming years. Some patients can require colectomy for medically refractory disease or to treat colonic neoplasia. Treatments for ulcerative colitis include 5-aminosalicylic acid drugs, steroids, and immunosuppressants.

The aim of management is to induce and then maintain remission, defined as resolution of symptoms and endoscopic healing. Ulcerative colitis usually presents with bloody diarrhoea and is diagnosed by colonoscopy and histological findings. Patients with ulcerative colitis have mucosal inflammation starting in the rectum that can extend continuously to proximal segments of the colon. The pathogenesis is multifactorial, involving genetic predisposition, epithelial barrier defects, dysregulated immune responses, and environmental factors. Ulcerative colitis is a chronic inflammatory disease affecting the colon, and its incidence is rising worldwide.

Immune system indicators in ulcerative colitis