Small intestine and appendix Flashcards
List the symptoms and signs of acute appendicitis
Symptoms:
- Abdominal pain, starting dull and central before becoming localised and sharp in the RIF at McBurneys point (1/3rd of the way between the ASIS and the umbilicus)
- Constipation (or sometimes diarrhoea)
- Anorexia
- Nausea & vomiting (after the pain)
Signs:
- Rebound (when examiner moves hand away) tenderness in RIF
- Percussion tenderness
- Guarding
- Rosving’s sign (more painful in RIF than LIF when LIF pressed)
- Tachycardia
- Mild fever, flushing and fetor
- Tender mass (ocassionally)
- Psoas sign (pain on R hip extension: retropertioneal retrocaecal appendix)
- Obturator sign (pain on internal rotation of R hip: pelvic appendix)
What other conditions that mimic acute appendicitis?
(other differential diagnosis’)
- Mesenteric lymphadenitis (inflammation of lymph nodes)
- Ovarian cyst rupture
- Eptopic pregnancy
- Caecal volvulus
- Psoas abscess
- Diverticulitis
- IBD
- Cancer
- Pyelonephritis
- Meckel’s Diverticulum
What investigations would you do for a patient with suspected acute appendicitis?
- PR (rectal examination)
- Pelvic examination in females
- Pregnancy test
- Bloods: FBC, U&E, CRP/ESR
- Urinalysis
- USS/CT - if diagnostic uncertainity
- AXR/erect CXR - if questioning perforation
This diagnosis is made clinically and there usually isnt the need for all these tests (esp AXR/erect CXR and USS/CT)
What labatory findings would tend to confirm the diagnosis of acute appendicitis?
Raised WBC
Raised CRP
List the complications of a perforated appendix
(5)
- Peritonitis & sepsis (septicaemia)
- Appendix mass - inflamed appendix becomes covered with omentum
- Appendix abscess - Local/pelvic/subhepatic/subphrenic: develop if appendix mass fails to resolve
- Adhesions (fibrous bands that form between tissues and organs)
- Infertility - due to tubal obstruction after pelvic infection
What are common complications following an appendicetomy?
Early complications:
- Haematoma( a solid swelling of clotted blood within the tissues)
- Wound infections
Late complications:
- Small bowel obstruction (adhesions)
- Incisional hernia
How is the cause of a mass in the RIF diagnosed?
I.e what investigations are required?
- USS/CT to confirm diagnosis (use clinical signs to make inital diagnosis)
What are the possible differenial diagnosis’ for a mass in the right iliac fossa?
- Inflammatory mass (appendix ass/abscess)
- Lymphoma
- Crohn’s disease - Repeated inflammation and fibrosis may cause a thickening
- Tumour mass (caecal/carcinoid)
- Pelvic kidney - transplanted in RIF as external iliac vessels are easy to construct anastomosis with the existing renal vasculature stubs
How is a mass in the RIF managed?
(after USS/CT to confirms diagnosis)
- Conservative management
- IV cefuroxime and metronidazole, marking out the size of the mass to see if it develops into an abscess
- If the mass does not resolve (20% enlarge in a toxic patient), perform percutaneous drainage of abscess
- After resolution, interval appendectomy is usually carried out at three months due to the risks of further attacks
What is a carcinid tumour?
Describe in detail
(not one of the objectives)
- Tumours of argentaffin cells, which produce physically active substances such as serotonin/prostaglandins
- They can often occur on the tip of the appendix, and 10% of tumours may be assoiciated with MEN-1 syndrome
- They charactistically take up silver stains very readily
- Usually present after the fourth decade with carcinoid syndrome (flushing of the face and diarrhoea due to the endocrine products)
- Prognosis is generally good, and the tumour is generally resectable
What is the cause of Meckel’s diverticulum?
What is Meckel’s diverticulum - where?
- Caused by a remnant of the embryological vitelloinstestinal duct (2% of population have it)
- Only 2% of people with Meckel’s develop symptoms
- The diverticulum is 2cm long, on the antimesenteric border of the bowel, 20 inches from the ileocecal valve
- It may be lined by gastric acid secreting epithelium, or heterotropic pancreatic tissue
What are the possible patholigical effects of Meckel’s diverticulum?
-
Caecal volvulus
- part of the colon twists on its mesentery, resulting in acute, subacute, or chronic colonic obstruction
- If tethered to the umbilicus, the diverticulum may act as the apex of a volvulus to present like a volvulus with obstruction
-
Intussusception
- Part of the intestine folds into the section next to it
- Often gangrenous by the point of operation
-
Appendicitis
- Diverticulum becomes inflamed, presenting identical to appendicitis (sometimes also with umbilical cellulitis)
-
Peptic ulceration
- Pain around umbilicus that is related to mealtimes, due to ulceration of the gastric acid secreting epithelium
- A sinus tract may also exist between the diverticulum and the umbilicus (patent viteloointestinal duct)
Describe the signs and symptoms in a patient with intestinal obstruction
Symptoms:
- Vomiting
- Undigested food suggests gastric outlet obstruction
- Bilous vomiting suggests upper small bowel obstruction
- Faeculent vomiting (thicker/foul-smelling) suggests more distal small bowel obstruction
- Pain
- Colicky abdominal pain in early obstruction
- Pain may be absent in long-standing obstruction
- Constipation
- May not be absolute (no passage of wind) in proximal obstruction
Signs:
- Distention
- Tinkling bowel sounds
- Dehydration
- Central resonance to percussion, dull flanks
- Scars: previous surgery causing adhesions
- Palpable mass (causing obstruction)
- NO abdominal tenderness (unless strangulation)
List the common causes of small bowel obstruction
- Adhesions (80%) - extramural
- Hernias - extramural
- Crohn’s disease - intramural
- Intussusception (part of the intestine folds into the section next to) - intramural
List the common causes of large bowel obstruction
- Carcinoma of the colon - intramural
- Diverticular disease - intramural
- Sigmoid volvulus - extramural
- Constipation (forgein body or faecal impaction ect) - intraluminal
What are the complications of bowel obstruction?
- The bowel wall becomes oedematous (tissue with excess interstitial fluid) and distends
- Bacteria proliferate in the obstructed bowel
- As the bowel distends, vessels become stretched and the blood supply is compromised, leading to strangulation (→ ischaemia & necrosis)
- Eventually the bowel will perforate
- Symptoms develop more gradually in large bowel obstruction due to the capacity (even greater if the ileo-caecal valve is incompetent)
What investigations should be done for a patient with suspected small intestinal obstruction?
- Bloods: FBC, U&Es, Amylase, LFTs
- ABG
- Urinalysis
- Supine AXR: distened proximal bowel, absent gas distally
- Erect CXR: fluid levels in small bowel obstruction, air under diaphragm if perforation
- Contrast enema: differentitates obstruction and pseudo-obstruction, can identify the level of obstruction and ileo-caecal competency (gastrograffin may also have therapeutic effect)
- CT scan: can indicate level of obstruction, but cannot always give the diagnosis
Interpret these AXRs
Bowel obstruction on AXR; (1) Small bowel obstruction, showing valvulae conniventes crossing a dilated, centrally-located bowel; (2) Large bowel obstruction, with peripherally located dilated bowel segments
Small bowel - >3cm = dilated. The valvulae conniventes run the whole way across the small bowel
Large bowel - >5cm = dilated. The haustra do not run the whole way across the large bowel.
Compare and contrast small to large bowel obstruction
Vomiting:
- Absent/faeculant in LBO
- Bilous in SBO
Constipation:
- Absolute in LBO
- May not be absolute in SBO
Progression:
- More rapid in SBO
The best differentitator is plain film radiograph of the abdomen
What is irritable bowel syndrome (IBS)?
IBS is a mixed group of abdominal symptoms for which no organic cause can be found. There may be differences in the ‘brain-gut’ axis, leading to increased visceral perception and decreased visceral pain threshold.
Describe the symptoms that may suggest a diagnosis of Irritable bowel syndrome (IBS)
- In the the preceding 12 months there should be at least 12 consecutive weeks of abdominal discomfort or pain, with 2/3 of the following features:
- Relieved with defecation
- Onset associated with a change in frequency of stool
- Onset associated with a change in form of stool
- Other symptoms:
- Bloating
- Passage of mucus
- Stool passage symptoms (tenesmus, feelings of incomplete evacuation)
- Associated gynaecological symptoms (dysmenorrhoea [painful periods]/dyspareunia [pain with sex]), urinary symptoms (frequency, urgency, nocturia) or back pain
It has prevalence of around 10-20%, with F:M >2:1, and onset before 40 years
Describe the epidemiology and risk factors for Crohn’s disease
- Prevalence of 50/100,00
- Male=Female
- Incidence peaks at 15-30, and also again in the 60s
Risk factors:
- Poor diet
- Family history
- Smoking
- Altered immune states
Describe the morphology and pathology of Crohn’s disease
I.e where in the body is affected? It appearance?
- Inflammation can affect any part of the GI tract (mouth to anus)
- Most commonly terminal ileum and ascending colon
- Can affect just one area, or multiple areas leaving normal bowel in between
- Skip lesions
- Involved bowel is narrowed due to the thickened wall, with deep ulcers
- ‘Rose-thorn ulcers’
- ‘Cobblestone’ appearance on CT (specific to Crohn’s, not seen on XR)
- Inflammation extends through all layers of the bowel
- Fistulae and stenosis are common
What are the clinical features of Crohn’s disease?
- Abdominal pain (varying character)
- Diarrhoea (steatorrhoea in ileal disease, bloody in colonic disease)
- Weight loss (or failure to thrive -FTT)
- Sever apthous ulceration of the mouth (early sign)
- Anal complications (fissure, fistula, haemorrhoids, skin tags, abscesses)
- Extra GI manifestations
- Can present with acute RIG pain/mass
Describe the epidemiology for ulcerative colitis
- Affects 100-200/100,000, again with a peak at 15-30 and also around 60
- Smoking is protective
- Females>Males
Describe the morphology and pathology of ulcerative colitis
I.e where in the body is affected? It appearance?
- Inflammation that starts in the rectum, extending proximally along the colon
- Proctitis if affects the rectum alone
- In some patients there can also be inflammation of the distal terminal ileum
- Backwash ileitis
- The inflammation only affects the mucosa, which is excessively ulcerated
- Gives adjacent mucosa the appearance of inflammatory polyps
What are the clincal features of Ulcerative colitis?
- Crampy lower abdominal discomfort
- Gradual onset diarrjoea (often bloody)
- Urgency and tenesmus if disease confined to the rectum
- Extra-GI symptoms
Give an overview of how the Crohn’s and Ulcerative differ histologically
- Crohn’s: transmural inflammation, lymphoid hyperplasia and granulomas
- UC: muscosal inflammation, crypt abscesses and goblet cell depletion
Crohn’s
Ulcerative Colitis
Location
Anal involvement
Continuity
Fistulae
Histology
Smoking
Cure
Crohn’s
Ulcerative Colitis
Location
Mouth to anus
Colon only
Anal involvement
Often
Seldom
Continuity
Discontinuous ‘skip lesions’
Continuous from rectum
Fistulae
Common
Uncommon
Histology
Transmural inflammation, granulomas,
goblet cells present
Mucosal inflammation only, crypt abscesses,
goblet cell depletion
Smoking
Increases risk
Protective
Cure
Surgery less effective (skip lesions)
Cured by colectomy
What are extra-colonic (outside of the colon) manifestations of inflammatory bowel disease (IBD) - crohn’s and UC
- Eye disorders such as conjunctivitis and uveitis may occur in 5% of IBD patients
- Seronegative arthritis of the spine and peripheral joints occurs in 15% of IBD patients
- Sclerosing cholangitis and cholangiocarcinoma have a strong relationship with UC (but not Crohn’s)
- Erythema nodosum and pyoderma gangrenosum may be found in IBD patients.
What investigations would you do for a patient with suspected inflammatory bowel disease?
- Bloods:
- FBC, U&Es, CRP/ESR, LFT
- Serum iron/B12/folate if anaemia
- Stool studies
- Stool chart
- Microscopy x3 to exclude infective causes
- Calprotectin (may be ordered to rule out IBD n general practice)
- Radiology
- AXR/CXR in acute disease
- CT in Crohn’s - to look for complications
- Endoscopy
- Rigid/flexi sigmoidoscopy in UC
- Colonoscopy
- Endoscopic rectal biopsy may be taken
What operative procedures are used to treat IBD?
When and why are they preformed?
- UC
- surgery may be required if medical treatment does not control symptoms, if local complications such as toxic megacolon and perforation appear, and if disease length necessitates removal because of cancer risk
- A panproctocolectomy and ileostomy are performed, leaving an ileal spout (toxic, raised from skin, RIF).
- Crohn’s
- Surgery is used in treatment of complications: strictures, adhesions and obstruction
- Removal of bowel may be performed, with an ileorectal anastomosis
- If the rectum is involved, panproctocolectomy with ileostomy is an option
- Surgical treatment of abscess, fissures and fistulae is routine
