Passmedicine GI Flashcards
Features of familial adenomatous polyposis (FAP)
- Typically over 100 colonic adenomas
- Cancer risk of 100%
- 20% are new mutations
Screening for familial adenomatous polyposis (FAP) if known to be at risk
- If known to be at risk then predictive genetic testing as teenager
- Annual flexible sigmoidoscopy from 15 years
- If no polyps found then 5 yearly colonoscopy started at age 20
- Polyps found = resectional surgery
A 17-year-old boy is admitted to hospital with suspected appendicitis. He is found to be maximally tender at McBurney’s point. Where is this located?
McBurney’s point is found 2/3rds of the way along an imaginary line that runs from the umbilicus to the anterior superior iliac spine on the right-hand side.
Presentation of appendicitus
Peri-umbilical abdominal pain radiating to the right iliac fossa due to localised parietal peritoneal inflammation.
How is the diagnosis of appendicitis made?
Typically raised inflammatory markers coupled with compatible history and examination findings should be enough to justify appendicectomy.
Management of appendicitis
Appendicectomy which can be performed via either an open or laparoscopic approach. Laparoscopic appendicectomy is now the treatment of choice.
What is diverticulosis?
Diverticulosis describes the asymptomatic presence of diverticula in the colon.
What is diverticulitis?
When one of the divertiicula becomes infected
What is the classical presentation of diverticulitis?
- left iliac fossa pain and tenderness
- anorexia, nausea and vomiting
- diarrhoea
- features of infection (pyrexia, raised WBC and CRP)
Management of diverticulitis
- mild attacks can be treated with oral antibiotics
- more significant episodes are managed in hospital.
- Patients are made nil by mouth, intravenous fluids and intravenous antibiotics (typically a cephalosporin + metronidazole) are given
Abdominal X-ray shows multiple dilated small bowel loops.
In order to see dilated small bowel loops where must the site of obstruction be?
distal small bowel or proximal large bowel
What is the most likely cause of distal small bowel obstruction?
small bowel adhesions
What is the treatment for small bowel adhesions?
Treatment is with laparotomy and adhesiolysis to free up the affected bowel segment.
What are the retroperitoneal structures?
SAD PUCKER
- Suprarenal (adrenal) gland
- Aorta/IVC
- Duodenum (second and third part)
- Pancreas (except tail)
- Ureters
- Colon (ascending and descending)
- Kidneys
- Esophagus
- Rectum
Where does Crohn’s disease affect?
It commonly affects the terminal ileum and colon but may be seen anywhere from the mouth to anus.
Features of Crohn’s disease
- presentation may be non-specific symptoms such as weight loss and lethargy
- diarrhoea: the most prominent symptom in adults. Crohn’s colitis may cause bloody diarrhoea
- abdominal pain: the most prominent symptom in children
- perianal disease: e.g. Skin tags or ulcers
- extra-intestinal features are more common in patients with colitis or perianal disease
Extraintestinal features of Crohn’s disease
- Arthritis
- Erythema nodosum
- Episcleritis
- Osteoporosis
- Clubbing
Investigations for Crohn’s disease
- raised inflammatory markers
- increased faecal calprotectin
- anaemia
- low vitamin B12 and vitamin D
What type of screening is offered for colorectal cancer?
The NHS offers home-based, Faecal Immunochemical Test (FIT) screening every 2 years to all men and women aged 60 to 74 years in England, 50 to 74 years in Scotland.
What is the most common type of tumour encountered in the colon?
Adenocarcinoma
Location of colorectal cancer
- rectal: 40%
- sigmoid: 30%
- descending colon: 5%
- transverse colon: 10%
- ascending colon and caecum: 15%
What is the most likely causative organism in pseudomembranous colitis following recent broad-spectrum antibiotic use?
What is the microbiology report most likely say about the causative organism?
Clostridium difficile
This is a gram-positive bacillus
Features of Clostridium difficile infection
- diarrhoea
- abdominal pain
- a raised white blood cell count is characteristic
- if severe toxic megacolon may develop
Clostridium difficile infection diagnosis
- is made by detecting Clostridium difficile toxin (CDT) in the stool
- Clostridium difficile antigen positivity only shows exposure to the bacteria, rather than current infection
