Colorectal Cancer Flashcards
(146 cards)
What is irritable bowel syndrome (IBS)?
A chronic illness characterised by abdominal pain/discomfort and disturbed bowel habit in the absence of causative disease.
Which gender is more prevalent for IBS?
Women.
What criteria is used to diagnose IBS?
The Rome Criteria.
What are the diagnostic criteria for IBS according to the Rome Criteria?
12 weeks of abdominal discomfort or pain with:
* Relief by defaecation
* Associated with change in stool frequency and appearance.
What are common symptoms supporting the diagnosis of IBS?
- Bloating
- Abdominal distention
- Passing mucus
- Abnormal stool frequency and form.
long history with relapse and remitting course, exacerbations aretirggered by life events, co-morbidity of anxiety/depression and symptoms worsened by eating.
What is a major pathophysiological aspect of IBS?
Increased contractility of intestinal muscles with increased sensitivity to visceral stimulation and underlying inflammation linked to stress. Gut mucosa in IBS shows chronic inflammatory cells mas cells and IBS-D (diarrhoea) will have more mucosal T lymphocytes than IBS-C.
What are common triggers for IBS exacerbations?
- Life events
- Co-morbidity of anxiety/depression
- Symptoms worsened by eating.
What are alarm features of IBS?
- Onset after age 50
- Progressive deterioration
- Weight loss
- Fever
- Rectal bleeding
- Steatorrhoea
- Dehydration
- Family history of organic gastrointestinal disease.
What investigations are recommended for IBS?
- FBC with metabolic panel
- Inflammatory markers
- Stool culture for C-diff, giardiasis, cryptosporidium
- Testing for coeliac with tissue transglutaminase antibody
- Colonoscopy.
What treatment options are available for IBS?
- Non-stimulant osmotic laxatives (e.g., macrogol)
- Anti-spasmodics (e.g., mebeverine, hyoscine butylbromide)
- Anti-diarrhea agents (e.g., loperamide)
- Anti-depressants (e.g., tricyclics and SSRIs)
- Dietary management (FODMAPs)
- Rifaximin.
True or False: There is a strong association of IBS with anxiety and depression.
True.
What is small bowel obstruction (SBO)?
A surgical emergency characterised by a triad of abdominal pain, vomiting, and abdominal distention which disrupts intestinal flow.
What are the categories of small bowel obstruction?
- Simple obstructions
- Functional obstruction
- Strangulated obstructions.
What is the cause of simple obstruction?
gallstone ileus (At ileocaecal valve))intramural lesion or extrinsic adhesion, causing proximal bowel distention and distal bowel decompression which increases intraluminal pressure alternative causes include volvulus, strictures and tumours
What is the cause of functional obstruction?
peristalsis due to metabolic disturbances like hypothyroidism or phaechromocytoma, neural inhibiton or inflammation.
What causes strangulated obstruction?
Bowel ischaemia
Hernia
Malignancy from cancer, typically carcinoid, adenocarcinoma and gastro-intestinal stromal tumour
Inflammation from conditions like Crohn’s disease with intestinal fistula and abscess
Endometriosis of the intestine
Intestinal reduced motility
What is the pathophysiology of SBO?
there will be bowel wall oedema, hyperaemia, fluid loss, and increased permeability to bacteria with risk of ischaemia and infarction and systemic effects of fluid loss. Prolonged ischaemia can lead to necrosis of the wall and result in liquefactive necrosis and vascular thrombosis in mesenteric vein.
What are common causes of small bowel obstruction?
- Post-operative adhesions
- Gallstone ileus
- Intramural lesions
- Extrinsic adhesions
- Volvulus
- Strictures
- Tumours.
What are the clinical presentations of small bowel obstruction?
- Acute abdominal pain
- Vomiting
- Dehydration
- Abdominal distention
- Tenderness over obstruction site.
How does proximal SBO present?
significant vomiting, rapid dehydration/electrolyte imbalance and minimal abdominal distention.
How does distal SBO present?
Distal SBO will have extreme abdominal distention, delayed vomiting and slower onset of systemic electrolyte imbalances.
What diagnostic tests are used for SBO?
- FBC for leukocytosis
- Hydration status and electrolytes
- ABG for metabolic alkalosis or lactic acidosis
- Upright chest radiograph
- CT scan.
What is the initial treatment for small bowel obstruction?
Fluid resuscitation and broad-spectrum antibiotics.
What complications can arise from small bowel obstruction?
- Bowel ischaemia
- Perforation
- Further adhesion formation
- Malnutrition
- Peritonitis.