18. Small Bowel Disease Flashcards
What are 3 forms of congenital small bowel disease?
Meckel’s diverticulum
Atresia
Stenosis
What is Meckel’s diverticulum?
Vitello-intestinal duct fails to disappear
What is the difference between atresia and stenosis?
In atresia no lumen develops
In stenosis the lumen is narrowed
What are non-infectious causes of inflammation in the small bowel?
Radiation enterocolitis
GvHD
IBD
What is coeliac disease?
Atrophy of villi caused by an immune response to the gliadin fraction of gluten
What genes are associated with coeliac disease?
HLA DQ2 and DQ8
How is coeliac disease diagnosed?
Small bowel biopsy
Serum endomysial and TTG antibodies
What is seen on histology in coeliac disease?
Villus atrophy
Crypt hyperplasia
Epithelial damage (TTG usually protects barrier)
Chronic inflammation
What extra-GI disorders are associated with coeliac disease?
Dermolitis herpetiformis
Endocrine disorders
What are the long term complications of coeliac disease?
EATL Adenocarcinoma Ulceration Strictures caused by fibrosis Splenic atrophy Malnutrition
What is giardiasis?
Giardia is a protozoa which causes patchy villus abnormality
Acquired by faecal contamination of water
Included in the differential for coeliac disease
What is seen in giardiasis on histology?
Trophozoite (feeding stage of protozoa) along epithelial surface
How is giardiasis detected?
Antigen test on stool
What is Whipple’s disease?
Caused by an actinomycete can affect any organ
What is seen on histology in Whipple’s disease?
Accumulation of lipids in lamina propia
Foamy macrophages full of pathogen
What are the causes of obstruction in the small bowel?
Hernia
Adhesions
Intussusception
Volvulus
What is intussusception?
Proximal segment of bowel telescopes into distal segment
What is volvulus?
Bowel twists around its mesenteric base
What benign neoplasms can be found in the small bowel?
Adenomas
Hamartomatous polyps (Peutz Jegher)
Lipomas, leimyomas
What are the most to least common malignant neoplasms in the small bowel?
Primary GI lymphoma
Carcinoid tumours
Adenocarcinoma
What are the causes of adenocarcinoma?
Long term Crohn’s or coeliac disease
FAP
What forms of primary GI lymphomas can be found in the small bowel and what tumour markers do they have?
EATL (CD3+)
MALToma (CD20+)
Which tumour marker shows how proliferative the cells are?
ki-67
What are the symptoms of carcinoid syndrome?
Facial flushing
Intestinal hypermobility
Bronchoconstriction
RH abnormalities
What are the causes of acute appendicitis?
Obstruction with mucin and bacterial infection
Due to generalised viral illness
What are the types of acute appendicitis?
Acute focal
Acute suppurative
Gangrenous
Perforated
What diseases can involve the appendix?
IBD
Sarcoid
Yersinia
What tumours/tumour like conditions can involve the appendix?
Carcinoid
Mucocoele
Mucosal hyperplasia
Mucinous cystadenoma/cystadenocarcinoma
