Pathology of the small bowel Flashcards
What is Meckles diverticulum ?
- It is a congenital diverticulum of the small intestine.
- It is an embryological remnant of the vitellointestinal duct and contains ectopic ileal, gastric or pancreatic mucosa
What is the rule of 2s reagrding meckles diverticulum ?
- occurs in 2% of the population
- is 2 feet from the ileocaecal valve
- is 2 inches long
What are the presenting features of meckles diverticulum ?
Usually asymptomatic but if it causes symptoms:
- Abdo pain mimicking appendicitis (when causing meckles diverticulitis)
- Rectal bleeding
- intestinal obstruction - secondary to an omphalomesenteric band (most commonly), volvulus and intussusception
Who is meckles diverticulum more common in, males or females ?
Much more common in males
What are the potential complications of meckles diverticulum ?
- Bleed (haematochezia) = fresh red blood
- Ulcerate/meckels diverticulitis - more common in adults
- Obstruction - more common in adults
- Malignant change (0.5%)
What is meckles diverticulum the most common cause of ?
Painless massive GI bleeding requiring a transfusion in children between ages 1-2
What is the management of meckles diverticulum ?
Removal if it has a narrow neck or is symptomatic
Are primary tumours of the small bowel common ?
No they are very rare
What are the potential primary tumours of the small bowel ?
- Lymphomas - non-hodgkins (B or T cell)
- Carcinoid tumours
- Carcinomas
What type of tumours and where from are much more common of the small bowel ?
Metastases (secondary) from:
- Ovary
- Colon
- Stomach
What is the treatment of primary lymphomas of the small bowel ?
Surgery and chemo
What is a carcinoid tumour ?
- A rare small, yellow ,slow growing tumours which is usually locally invasive
- They produce serotonin (5-HT) + other hormones
Where do carcinoid tumours usually arise ?
- Appendix
- Ileum
- Rectum
What complications can carcinoid tumours result in ?
- Can cause intussusception, obstruction
- Can metastases to liver causing carcinoid syndrome
If a carcinoid tumour metastases to the liver how do they result in carcinoid syndrome ?
Because they are then able to now release serotonin into the systemic circulation
What are the features of carcinoid syndrome ?
- Flushing (often earliest symptom)
- Diarrhoea
- bronchospasm
- hypotension
- right heart valvular stenosis (left heart can be affected in bronchial carcinoid)
- other molecules such as ACTH and GHRH may also be secreted resulting in, for example, Cushing’s syndrome
What is used to manage carcinoid syndrome ?
- Octreotide (somatostatin analogue) - used to counter peripheral effects and tumour mediators
- Diarrhoea: cyproheptadine or loperamide may help
What are carcinomas of the small bowel associated with ?
Crohns disease and coeilac disease
How do carcinomas of the small bowel tend to present ?
Late with metastases to the lymph nodes and liver
Who is appendicitis most common in ?
- Young people aged 10-20
- Note it can occur at any age however
What are the typical symptoms of appendicitis?
- Peri-umbilical pain (central) which migrates to the RIF
- Pain is often worse on coughing or going over speed bumps (children cant hop on one leg)
- Nausea with one or two episodes of vomiting - marked is unusual
- Mildly pyrexic - 37.5-38oC.
- Anoxrexia (loss of appetite)
What are the signs of appendicitis ?
- L ocalised peritonism (in RIF) causing gaurding or rebound - Generalised peritonitis if perforation has occurred
- Rovsings sign - palpation in LIF causes pain in the RIF
- PR exam may feel - boggy sensation if pelvic abscess is present, or even right-sided tenderness with a pelvic appendix
- Increased WCC
- Mild pyrexia and tachycardia
- Psoas - Patient keeps the right hip flexed as this lifts an inflamed appendix off the psoas
- Obturator - If appendix is touching obturator internus, flexing the hip and internally rotating will cause pain
How is appendicitis usually diagnosed ?
1st line = raised inflam markers + history/exam findings
What needs to be excluded in aptients with appendicitis ?
- Urine dipstick + pregnancy test - to exclude UTI or pregnancy/ectopic pregnancy
