Intestine Disorders Flashcards
What are plicae circulares?
Folds in the small intestine
What are red spots seen on the small intestine?
Peyer’s patches
What is the main epithelial adaptation of the small intestine?
Lots of villi
What type of pain does a small bowel obstruction have?
Colicky or central
Apart from pain, what are other symptoms of a small bowel obstruction?
Constipation, burping, vomiting, abdominal distension
How do you assess the state of a patient with a small bowel obstruction?
Urinalysis, bloods, ABGs
How do you confirm the diagnosis of a small bowel obstruction?
AXR and contrast CT
How do you treat a small bowel obstruction?
ABC’s, analgesia, fluids with potassium, catheter, NG tube
What are complications can patients with small bowel obstructions get?
Hypokalaemia and alkalotic
What are the two different types of small bowel ischaemia?
Mesenteric artery occlusion or non-occlusive perfusion insufficiency
What are causes of mesenteric arterial occlusion?
Mesenteric artery atherosclerosis, thromboembolism from the heart e.g. AF
What are causes of non-occlusive perfusion insufficiency?
Shock, hernia, drugs, hyperviscosity
The degree of bowel infarction increases with what?
The time of ischaemia
What is the outcome of a mucosal infarct?
Regeneration
What is the outcome of a mural infarct?
Stricture
What is the outcome of a transmural infarct?
Gangrene and death if not resected
How is small bowel ischaemia diagnosed?
Acidosis, lactate elevated, CRP can be normal, WCC raised, CT angiogram
Meckel’s diverticulum results from what?
Incomplete regression of vitello-intestinal duct
Where should the vitello-intestinal duct normally connect?
Yolk sac
What is Meckel’s diverticulum?
Tubular structure about 2 inches long about 2 foot above the ileocaecal valve
What can Meckel’s diverticulum cause?
Bleeding, perforation, diverticulitis
Where is secondary metastases to the small bowel commonly from?
Ovaries, colon, stomach
What are primary tumours of the small intestine?
Non-Hodgkin’s lymphoma, carcinoid tumours, carcinomas
What are carcinoid tumours?
From the neuroendocrine system
How can lymphomas be treated?
Surgery and chemotherapy
Where is the commonest site of a carcinoid tumour?
Appendix
What type of tumour can cause production of hormone like substances?
Carcinoid
What do carcinoid tumours cause if they metastasise to the liver?
Flushing and diarrhoea
What are primary carcinomas of the small bowel associated with?
IBD
What is the commonest cause of acute abdominal pain?
Appendicitis
How does appendicitis present?
Vomiting, abdominal pain (specifically RIF), RIF tenderness, increased WCC
What are some signs of acute appendicitis?
Mild pyrexia, tachycardia and guarding
What are investigations for appendicitis?
Ultrasound, AXR, bloods (WCC, CRP), urinalysis
How is appendicitis managed?
Analgesia, antipyretics, antibiotics, surgery
What are complications of appendicitis?
Peritonitis, rupture, abscess, fistula, sepsis
Acute inflammation must involve what?
Muscle coat
Coeliac disease is caused by an abnormal reaction to what?
Gliadin- a component of wheat, flour and gluten
What does the abnormal reaction in Coeliac disease do?
Damages enterocytes and reduces absorptive capacity
What other conditions can Coeliac disease be related to?
Dermatitis herpetiformis, childhood diabetes
The abnormal reaction in Coeliac disease is mediated by what?
T lymphocytes
What will be seen on histology of Coeliac?
Loss of villous structure (villous atrophy)
Where are the lesions from Coeliac worse?
Proximal bowel
What are good things to test for on serology of Coeliac?
Anti- tissue transglutaminase, anti- gliadin
What is a comfirmative test for Coeliac?
Biopsy
Malabsorption of fats in Coeliac leads to what?
Steatorrhoea
Reduced intestinal hormone production in Coeliac leads to what?
Reduced pancreatic secretions and bile flow leading to gallstones
How can Coeliac present?
Weight loss, anaemia (Fe, B12, folate), abdominal bloating, failure to thrive
What are some complications of Coeliac?
Increased risk of small bowel lymphoma/carcinoma, gallstones
What causes lactose malabsorption?
Deficiency of lactase
What is a common history of lactose intolerance?
Diarrhoea, abdominal discomfort and flatulence following lactose ingestion
How is lactose intolerance diagnosed?
Lactose breath hydrogen test
What is tropical sprue?
Colonisation of the intestine by an infectious agent or alterations in intestinal bacterial flora
How is tropical sprue diagnosed?
Biopsy
How is tropical sprue treated?
Tetracycline and folic acid
How is Whipple’s disease diagnosed and treated?
Diagnosed by microscopy and treat with antimicrobial
What is short bowel syndrome defined as?
Small bowel < 200cm
What is the indication for home parenteral nutrition in short bowel syndrome?
< 50cm bowel
What is the last resort treatment for short bowel syndrome?
Small bowel transplant along with liver transplant
What are indications for a transplant for short bowel syndrome?
Loss of venous access or liver disease
What is diverticular disease related to?
Low fibre diet and increased intra-luminal pressure
Where in the colon is diverticular disease common?
Sigmoid colon
What will be seen in a colonoscopy of diverticular disease?
Holes in the bowel wall through the mucosa
What are clinical features of diverticular disease?
LIF pain/tenderness, sepsis and altered bowel habit
How do you treat uncomplicated diverticular disease?
Oral or no antibiotics- no IV fluids
What are complications of diverticular disease?
Inflammation, rupture, abscess, fistula, bleeding
In diverticular disease, a fistula to where is most common?
Bladder
What is 1st line treatment for complicated diverticular disease?
Percutaneous or laparoscopic drainage
What is 2nd line treatment for diverticular disease?
Remove section of colon or primary resection/anastomoses
What will show withering of crypts and smudging of lamina propria?
Ischaemic colitis
Who is ischaemia of the bowel most common in?
Elderly patients, particularly with pre-existing CVS disease
What are some causes of ischaemic colitis?
Embolus, atherosclerosis of mesenteric vessels, shock or vasculitis
What are complications of ischaemic colitis?
Bleeding, rupture, stricture
What will any type of colitis show on an X-ray?
Smooth colon- lead piping
What shows patchy yellow membranous exudate on the mucosal surface?
Pseudomembranous colitis
What will pseudomembranous colitis show on histology?
Explosive lesions on mucosa
What is a common cause of pseudomembranous colitis?
Use of broad spectrum antibiotics and C. diff infection
What are symptoms of pseudomembranous colitis?
Diarrhoea and bleeding
How is pseudomembranous colitis treated when severe?
Colectomy- may be fatal
What causes a thickness of sub-epithelial collagen?
Collagenous colitis
What does collagenous colitis present with?
Watery diarrhoea
What will show normal crypt architecture with a massive increase in intra-epithelial lymphocytes?
Lymphocytic colitis
What type of colitis is common in people with a history of cancer?
Radiation colitis
What will cause a busy epithelium with no irregular crypts?
Infective colitis
What can be causes of large bowel obstruction?
Cancer, benign strictures, volvulus or hernias
What is the normal treatment for a large bowel obstruction?
Insert a stent
What are some symptoms of large bowel obstruction?
Constipation, abdominal distension, pain and vomiting
What is the relative onset of vomiting in small and large bowel obstructions?
Early in small bowel obstruction and late in large bowel obstruction
What happens in a volvulus?
Bowel gets twisted on mesentery
What part of the large bowel is a volvulus most common in?
Sigmoid colon
What can the area infarcted by a sigmoid volvulus become?
Gangrenous
How is the diagnosis of sigmoid volvulus made?
Plain AXR and rectal contrast
Irritable bowel syndrome is a chronic, relapsing condition involving what?
Abdominal pain, bloating and change in bowel habit
What are slightly more uncommon symptoms of IBS?
Mucus in stool, urgency, tenesmus, aggravated by stress
What are investigations for IBS?
FBC, plasma viscosity, CRP, TTG (check for coeliac)
What are some lifestyle options for IBS?
Regular meal times, reduced fibre/tea/coffee
What medications can be given for IBS?
Anti-diarrhoeals, spasmodics, depressants
What is the Rome II criteria for IBS?
Recurrent abdominal pain and discomfort for at least 3 days per month for 3 months and 2 or more of:
- Improvement with defaecation
- Associated with a change in stool frequency
- Associated with a change in stool form
What is a polyp?
A protrusion above an epithelial surface
What do most polyps tend to be?
Adenomas
Why should all adenomas be removed?
They are all dysplastic and precursors of adenocarcinomas
Colorectal cancer is more common on which side?
Left
What are some presenting complaints of left sided colorectal cancer?
PR bleeding, altered bowel habit, obstruction
What are some presenting complaints of right sided colorectal cancer?
Anaemia and weight loss
When is hereditary non-polyposis coli more common?
< 100 polyps involved
What is familial adenomatous polyposis more common?
> 100 polyps involved
Which genetic predisposition to colorectal cancer has an early onset and which late?
FAP- early onset
HNPCC- late onset
Which genetic predisposition to colorectal cancer has a defect in DNA mismatch repair?
HNPCC
Which genetic predisposition to colorectal cancer has a defect tumour suppression?
FAP
What mode of inheritance do both HNPCC and FAP involve?
Autosomal dominant
Which genetic predisposition to colorectal cancer affects right sided tumours and which affects all throughout the colon?
Right side- HNPCC
All through- FAP
What type of tumours does HNPCC produce?
Mucinous tumours
What type of tumours does FAP produce?
Adenocarcinoma
Which of the genetic predispositions to colorectal cancer involves inflammation?
HNPCC
What does an oncogene do?
Normally promotes cell growth and division, when mutated causes excess of this
What does a tumour suppressor do?
Normally suppresses growth and division, when mutated allows this
What are the sites of colorectal cancer from most to least likely?
Rectum Sigmoid colon Ascending colon Transverse colon Descending colon
What are lifestyle factors which are protective against colorectal cancer?
Vegetables, fibre, exercise
What are lifestyle factors which are causative of colorectal cancer?
Processed meat, smoking, alcohol, obesity
What are general findings of colorectal cancer?
Anaemia, cachexia, lymphadenopathy, mass, distension
What are potential emergency presentations of colorectal cancer?
Obstruction, bleeding, perforation
How is colorectal cancer diagnosed?
CT colonoscopy, colonoscopy, sigmoidoscopy, barium enema, faecal occult blood test
What is the main treatment for colorectal cancer?
Surgery
When is radiotherapy used in colorectal cancer?
Pre or post op to prevent recurrence, or palliatively
What causes intestinal failure?
Inability to maintain adequate nutrition or fluid status via the intestines
Which types of intestinal failure are acute?
1 and 2
Which types of intestinal failure are chronic?
3
What is a common cause of acute intestinal failure?
Post operatively
What is a common cause of chronic intestinal failure?
Short gut syndrome
What are treatments for type 1 intestinal failure?
Replace fluids, correct electrolytes, acid suppression with PPIs
When should parenteral nutrition be used in type 1 intestinal failure?
If unable to tolerate oral foods/fluids for more than 7 days
What are treatment options for type 3 intestinal failure?
Home parenteral nutrition, intestinal transplant, bowel lengthening (children)
What can being malnourished to feeding lots cause?
Severe heart failure
What is parenteral nutrition dependent on?
Venous access
What lines can be used for parenteral nutrition?
Peripherally inserted central catheter or tunnelled catheter (Hickman line)
Where can a Hickman line enter?
Subclavian or internal jugular vein
What are complications of parenteral nutrition lines?
Pneumothorax or arterial puncture
