Inflammation Of The Bowel Flashcards

Question

What drugs can affect the GI tract

Answer 1

NSAIDs – non-selective COX inhibitors e.g. indomethacin > specific COX-2 inhibitors 65% on long term use develop ulcers, erosions, usually distal ileum and duodenum, right colon Complications: perforations, focal active colitis, chronic NSAID enteropathy - 'diaphragm disease', usually affect ileum, suppositories - localised proctitis, ulceration, strictures

Answer 2

constitutive (continuously stimulated by body), produces prostaglandin for basic house-keeping purposes, stimulate normal body functions such as stomach mucous production, regulation of gastric acid and kidney water excretion

Answer 3

induced (not normally present in cells), produces prostaglandins for inflammatory response, used for signalling pain and inflammation

Answer 4

Complex ecosystem of microbes act as a natural barrier against colonisation by enteropathogens • broad spectrum antibiotics develop diarrhoea(antibiotic-associated colitis) • Iatrogenic disease caused by Clostridium difficle and its associated toxins resulting in fulminant colitis, profuse diarrhoea, dehydration and in some debilitated patients, death o C. difficle – spore-forming Gr+ anaerobe o 2 toxins – A and B detected in faeces o Primarily colonic, but may be accompanying ileitis, in immunosuppressed individuals o 25% all antibiotic-associated diarrhoea o Histologically, 'volcano'-like eruption of mucus, epithelial cells, neutrophils and fibrin on surface = pseudomembrane

Answer 5

Appendicitis Inflammation due to obstruction by faecoliths, food residues, lymphoid hyperplasia (children, viral infections), diverticulosis and neoplasia (carcinoid). Other aetiology: specific infections (Yersinia, tuberculosis), inflammatory bowel disease Complications o Abscess formation o Extensive necrosis (gangrenous) o Perforation o Spread of suppurative inflammation (liver) o Septicaemia

Answer 6

Common condition causing considerable morbidity in Western countries Due to high intraluminal pressure causing o Hypertrophy of muscular layers o Herniation of mucosa through area of weakness (where vessels enter into mucosa) - protrusion of diverticula which can be obstructed by faecoliths etc. Can occur anywhere in intestinal tract, sigmoid commonest site Abdominal pain, altered bowel habit, bleeding Complications o Diverticulitis – inflammation of diverticula o Pericolic abscess o Perforation o Fistula – communication between 2 organs

Answer 7

Mucosal inflammation limited to segment affected by diverticulosis Mucosa proximal and distal (rectum) normal Histologically, inflammation confined to mucosa with crypt architectural changes, but can be transmural with lymphoid aggregates and fistula formation – mimicking inflammatory bowel disease

Answer 8

Acute GI infection is major cause of morbidity throughout the world with viruses playing a leading role, and small intestine is usually main site Tuberculosis and Yersiniosis – affects terminal ileum/caecum, chronic granulomatous inflammation and endoscopically and histologically mimics Chron's disease

Answer 9

chronic relapsing condition encompassing Crohn's disease and ulcerative colitis

Answer 10

Proposed genetic defect that prevents a controlled and effective immune response to causative agent Support for genetic role from twin study: 44-70% monozygous twins had Crohn's compared to 4% in dizygous twins HLA-DR1 and DQw5 Frequency of involvement o Small intestines – 33% o Ileocolic – 45% o Large intestines – 20%

Answer 11

Higher incidence in northern Europe and US Incidence varies from 4-65 per 100,000 population Bimodal incidence (2 peaks): 20-30yrs and 60-70yrs, can occur in children Becoming more prevalent than ulcerative colitis Incidence rising in Asia

Answer 12

Cigarette smoking increases risk in genetically susceptible individuals Microvascular infarction – oral contraceptive pill (procoagulant) Triggers appear to be infective agents – e.g. mycobacteria, measles virus

Answer 13

Depends on disease location o Colon: bloody diarrhoea o Upper GI/small intestine: severe abdominal pain, vomiting, weight loss, small intestinal obstruction due to strictures o Perianal: ulcers, fissures, perianal abscess, fistula

Answer 14

Serosal fat wrapping 'Cobblestone' – transverse ulcers intersecting oedematous mucosa Serpiginous ulcers – longitudinal

Answer 15

Flat surface Crypt architecture often preserved Ulcer, patchy activity (cryptitis and crypt abscess o Plasma cell-rich infiltrate Granuloma Resection shows • Fissuring ulcers • Transmural chronic inflammation (affects all layers of wall) with lymphoid aggregates along muscular coat • Muscular hypertrophy and neural hyperplasia • Pyloric metaplasia – response to chronic inflammation/injury • Granuloma – collection of macrophages

Answer 16

Complications of disease process - e.g. fistula, strictures, intra-abdominal abscess, perforation Main principle of surgery is to preserve bowel length, avoiding short bowel syndrome and intestinal failure

Answer 17

Malabsorption – short loop/bowel syndrome Fistula formation Anal lesions (60%) – fissures, fistula Perforation, haemorrhage, toxic dilation not as frequent as ulcerative colitis Increased risk of malignancy of small intestine but less frequent than UC

Answer 18

Always begins in rectum Can remain limited to rectum (ulcerative proctitis) Extends proximally to a variable length, or involve the entire large intestine (pancolitis) in a continuous manner Changes always most severe distally Primarily affects mucosa, but in severe disease, deeper layers can be involved - fulminant colitis (toxic megacolon)

Answer 19

Peak incidence -3rd decade Can present in very young children or elderly Anglo-Saxon individuals – North America, North Western Europe, New Zealand, Scandinavia – approx. 100 per 100,000 population

Answer 20

Inappropriate immune response to an unknown environmental stimulus in the colon Unknown cause – infection, diet, environmental factors, primary immunological defects, abnormalities in mucin, genetic disorders, psychomotor disorder Appendicectomy may be protective, delay onset, producing a milder form Smoking appears to be preventive – could be linked to increased glycoprotein synthesis maintaining protective mucosal barrier QNSAIDs known to reactivate CIBD, especially UC, and in some patients, implicated in initiating UC

Answer 21

Length may be shortened, reduction in transverse calibre – increase in sarcorectal distance radiologically Normal serosa except in toxic megacolon Granular/valvety friable surface Ulcers – flasked-shaped, or undermining Polyps (inflammatory - granulation tissue) vs pseudopolyps (mucosal islands)

Answer 22

Irregular surface Diffuse crypt architectural distortion Diffuse chronic inflammatory cell infiltrate, rich in plasma cells

Answer 23

Resistance to medical therapy or dependence on unacceptable levels of therapy (majority of the patients on immunosuppression to dampen the body’s immune response) Severe disease Complications – dysplasia (unregulated cell proliferation), carcinoma

Answer 24

-Liver pathology – incidence depends on severity and extent of colitis, but significant liver problems in 5-8% -Coincidental – fatty change (nutritional and absorptive problems), cholelithiasis (CD>UC) -Primary sclerosing cholangitis – disease of biliary tract, most commonly seen with pancolitis (ulcerative colitis) o 1-5% of patients with IBD have PSC o 50-75% of patients with PSC have IBD -Skin – pyoderma gangrenosum, erythema nodosum -Eyes – iritis, uveitis, episcleritis -Joints – ankylosing spondylitis

Answer 25

11/100000 | 15-30 and 60-80

Answer 26

7/100000 | 15-30 and 60-80

Answer 27

1. 1:1 | 2. 1.8: 1

Answer 28

smoking-Prevent disease in ulcerative colitis and may cause it in crohns Appendectomy may be protective in ulcerative colitis Oral contraceptive relative risk of 1.9 in Crohn’s