GI track diseases II Flashcards
How is small intestinal bacterial overgrowth minimised?
peristalsis
acidic chyme leaving stomach
immunoglobulins
ileocaecal value
peristalsis
movement in one direction
acidic chyme leaving stomach
moderates bacteria growth
Key indicator of small intestinal bacterial overgrowth
SI bacteria ferment CHO producing gas
What improves symptoms in small intestinal bacteria overgrowth?
antibiotics
What worsens symptoms in small intestinal bacteria overgrowth?
Prebiotics
Carbohydrates
Dietary Fibre
Does increasing dietary fibre improve constipation demo small intestinal bacteria overgrowth?
no
Inflammatory bowl disease examples
Crohn’s disease
Ulcerative Colitis
Diverticulitis
Polyp
Familial Syndrome
Crohn’s disease
delimited (skip lesions, patch inflammation, pockets are inflamed) involvement of bowl in inflammatory process with mucosal damage, granulomas, formation of fistulae
What happens during Crohn’s disease?
Intestinal wall is thickened due to oedema, inflammation, fibrosis and hypertrophy of the muscular propria
Mesenteric fat wraps around bowel surface
lumen is narrowed - strictures (blockage)
What does repeated surgery on Crohn’s disease do?
causes short bowl syndrome
(maintain normal nutrition not possible)
Crohn’s disease clinical features - symptoms
vague and overlapping
- fever
- abdominal pain
- diarrhoea
Crohn’s disease complications
risk very high
- strictures, fistulas
What can Crohn’s disease affect?
terminal ileum
- resulting in loss of protein
- malabsorption of Vitamin B12 and bile salts
Crohn’s disease problems
extra-intestinal problems
polyarthritis
cubbing of finger tips
When does crohn’s disease infection occur?
abnormal track connecting 2 epithelial surfaces
often become infected forming an abscess
only present in Crohn’s disease and can help with differential diagnosis
Crohn’s disease as sustained microbial-induced inflammatory response
bacterial flagellum made up of protein flagellin
major antigen of salmonella and e.coil
E.coil flagellum (whip) for motility
flagellin dominant antigen in CD not found in UC or healthy control
however - only 50% of CD patients are antibody positive
Ulcerative Colitis
continuous colonic involvement beginning in rectum
affects mucosa and submucosa
extensive ulceration of mucosa - isolating islands o regeneration mucosa
Ulcerative Colitis - Clinical Features
bloody diarrhoea with lots of mucus
lower abdominal pain
similar systemic inflammatory complication to CD
Ulcerative Colitis - Percentage of Patients that will require colectomy within first 3 years
30%
Diverticulitis
blind pouch leading from GI tract lined with mucosa
Diverticulitis causes
- focal weakness in colon wall
- increased intraluminal pressure due to constipation
fragments of faecal matter stays in pouch, causes infection
Diverticulitis - treatment
low-fibre diet
reduced stool bulk
increased peristaltic activity and pressure
What are the two types of polyp?
hyperplastic and adenoma
Polyp
tumours mass arising from epithelium protruding into the gut lumen
Hyperplastic Polyp
decreased cell turnover
non-neoplastic - no cancer potential
do not have malignant potential
90% of all polyps
sporadic
Adenoma
epithelial proliferative dysplasia
neoplastic - turns into cancer
precursor of adenocarcinoma
familial predisposition
Familial Syndromes
familial adenomatous polyposis (FAP)
where is the mutation in familial adenomatous polyposis (FAP)
mutation in the adenomatous polyposis coil (APC) gene
