GI Conditions Flashcards
Name two types of inflammatory bowel disease
Crohn’s Disease
Ulcerative Colitis
Where does Ulcerative Colitis (UC) affect?
Usually begins in the rectum and can extend to involve the entire colon
Who is UC most commonly seen in?
Young adults
What GI symptoms can be seen in UC?
Mildly tender abdomen
Gross bleeding
Mucosal inflammation
Is there peri-anal disease seen with UC?
No
Describe the pathological appearance of UC
Chronic inflammatory infiltrate of the lamina propria
Continuous pattern
Pseudopolyps and crypt abscesses
Loss of haustra
What non-GI symptoms can be seen in UC?
Erythema nodosum (inflammation commonly seen in the shins) (affects ~30%)
MSK pain (affects ~50%)
What blood tests would be used to investigate UC?
Tests for serum markers and anaemia
What imaging techniques would be used to investigate UC?
Plain radiographs
Barium enema - lead pipe colon sign
CT/MRI (less useful)
Colonoscopy
What sample may be taken from a patient with suspected UC other than blood?
Stool samples for culture
How is surgery used in UC?
A colectomy performed for curative purposes, particularly in cases of:
Toxic megacolon
Pre-cancerous
Not settling with medical intervention
What medical interventions are used in UC?
Corticosteroids
Immunomodulators
Aminosalicylates - for flares and remission
Who is Crohn’s disease common in?
15-30 year olds and 60+ year olds
What part of the GI tract can Crohn’s affect?
ANYWHERE - ileum involved in most cases
What GI symptoms present with Crohn’s disease?
Tender RLQ
Mild peri-anal inflammation (75% of cases)
Gross bleeding (25%)
Fistula formation
Malnutrition - including mild anaemia
Describe the gross pathological appearance of Crohn’s disease
Skip lesions (non-continuous isolations)
Transmural - deep ulcers (can lead to fistulae)
Cobblestone appearance
Narrowing of bowel lumen
Hyperaemia
Describe the histological appearance of Crohn’s disease
Granuloma formation
Fibrosis
What imaging techniques can be used to investigate Crohn’s disease and what problems can they identify?
CT/MRI - obstructions, extramural problems, and bowel wall thickening
Barium enema/follow through (used less) - strictures/fistulae
Colonoscopy - bleeding, skip lesions, narrowing
What is looked for in blood tests in Crohn’s disease?
Anaemia
What medical interventions are used in Crohn’s disease?
THE SAME AS IN UC:
Corticosteroids
Aminosalicylates - for flares and remission
Immunomodulators
What type of surgery is used in Crohn’s disease?
Non-curative surgery to remove/repair strictures/fistulae
Name 3 defects of embryological origin that can affect the foregut
Pyloric stenosis
Abnormal positioning of the tracheoesophageal septum
Atresia or stenosis of the duodenum (can also be midgut depending on position)
Describe pyloric stenosis
There is narrowing of the stomach exit due to hypertrophy of the sphincter
How does pyloric stenosis present?
Projectile vomiting
What types of tracheoesophageal defects can occur?
Blind ended oesophagus
Fistula between trachea and oesophagus
Combinations of the two
How common are abnormalities of the tracheoesophageal septum?
~1/3,000 births
How can atresia/stenosis of the duodenum occur?
Lack of recanalisation after obliteration during development
Atresia/stenosis can occur in all parts of the intestine, where is it most common?
Duodenum > jejunum = ileum > colon
Name two embryological defects affecting the midgut
Malrotation
Vitelline duct defects
What are the two types of malrotation defects?
Incomplete rotation
Reversed rotation
What happens in incomplete rotation?
Only one 90˚ rotation
What is the result of an incomplete rotation?
Left sided colon
What happens in reversed rotation?
90˚ clockwise rotation
What is the result of reversed rotation?
The transverse colon passes posterior to the duodenum
What do both malrotation defects result in?
Hypermobile guts
What can hypermobile guts lead to an increased risk of?
Volvulus
What happens in a volvulus?
The bowel twists around itself
What can a volvulus risk?
Strangulation of the bowel, possibly leading to ischaemia and necrosis
What are the three types of vitelline duct defects?
Vitelline cyst
Vitelline fistula
Meckel’s diverticulum
What is the most common embryological GI abnormality?
Meckel’s diverticulum
Describe a Meckel’s diverticulum
An ileal cul-de-sac:
The vitelline duct fuses partially but remains as an out-pouching of the ileum
What ectopic tissue can present in a Meckel’s diverticulum?
Gastric tissue
What effect does ectopic gastric tissue have in Meckel’s?
Can release proteolytic enzymes as in the stomach and lead to ulceration
What mnemonic rule can be applied to Meckel’s?
The rule of 2’s
Explain the rule of 2’s of Meckel’s diverticulum
Affects 2% of the population
2:1 male to female ratio
Found 2ft from the iliocecal valve
2 inches long
Usually detected in under 2’s
Describe a vitelline cyst
A remnant of the Vitelline duct sealed at both ends and connected to the umbilicus and ileum by fibrous strands
Describe a vitelline fistula
Failure of the Vitelline duct to close, resulting in a direct communication between the ileum and the umbilicus
What can occur as a result of a vitelline fistula?
Faeces can leak out of the umbilicus
What embryological defects can affect the abdominal wall?
Gastroschisis
Omphalocoele
What happens in gastroschisis?
There is failure of the abdominal wall to close, causing the gut tube to herniate into the amniotic cavity
What happens at birth as a result of gastroschisis?
The gut tube remains outside of the body cavity with no covering
How does omphalocoele occur?
There is persistence of the physiological herniation of the gut tube
What happens at birth as a result of omphalocoele?
The gut tube remains herniated into the umbilical cord and is covered by a peritoneal layer
What embryological abnormalities can affect the hindgut?
Anal/anorectal agenesis
Imperforate anus
Hindgut fistulae
What is anal/anorectal agenesis?
Failure of the anal/anorectal canal to develop
What is a hind gut fistula?
Where the hindgut communicates with the urethra
What is an imperforate anus?
Failure of the anal membrane to rupture
What percentage of abdominal hernias do inguinal hernias account for?
75%
What percentage abdominal hernias do direct inguinal hernias account for?
25%
What types of inguinal hernias are there?
Direct
Indirect
What area of weakness is exploited in a DIRECT inguinal hernia?
Hesselbach’s triangle
What is the inferior border of Hesselbach’s triangle?
The inguinal ligament
What is the medial border of Hesselbach’s triangle?
Lateral border of rectus abdominis muscle
What is the lateral border of Hesselbach’s triangle?
The inferior epigastric blood vessels
What percentage abdominal hernias do indirect inguinal hernias account for?
50%
In a DIRECT inguinal hernia describe the route taken by the herniated viscera
The viscera herniates through Hesselbach’s triangle (medial to the inferior epigastric vessels) to sit behind the inguinal canal, pushing the posterior wall of the canal with it partially “through” the superficial ring.
In an INDIRECT inguinal hernia describe the route taken by the herniated viscera
The viscera passes through the deep ring of the inguinal canal (lateral to the inferior epigastric vessels), traverses through the inguinal canal and passes out through the superficial ring.
What other hernia can occur as a result of an indirect inguinal hernia?
Scrotal hernia
How does a scrotal hernia occur?
The processus vaginalis re-opens or fails to close properly, allowing the herniated viscera to pass into the scrotum via the same route the testis take during their descent
What happens in a femoral hernia?
The viscera passes through the femoral ring into the femoral canal and pass out through the saphenous opening
What sex are femoral hernias more common in?
Females
What do femoral hernias put the patient at risk of?
Incarceration (get viscera stuck) and resultant strangulation (blood supply cut off, risks ischaemia and necrosis)
At what stages in life can umbilical hernias occur?
Acquired infantile
Acquired adult
What is an infantile umbilical hernia?
The contents herniates through the weakness at the scar of the umbilicus
What is an adult umbilical hernia?
Technically a para-umbilical hernia where the contents herniates through the linea alba
Define gastro-oesophageal reflux disease
Excessive reflux of stomach contents into the oesophagus
What are the symptoms of GORD
Heartburn
Cough
Sore throat
Dysphagia
What can cause GORD?
Lower oesophageal sphincter problems
Delayed gastric emptying (leads to raised intra-gastric pressure)
Hiatus hernia (LOS slips though diaphragm and there is loss of
Obesity
What complications can GORD lead to?
Oesophagitis
Strictures
Barrett’s oesophagus
What is Barrett’s oesophagus?
Metaplasia of the squamous epithelium of the oesophagus to columnar
What does Barrett’s oesophagus increase the risk of?
Development of adenocarcinoma of the oesophagus (30-40x risk)
What are the three classes of treatment for GORD?
Lifestyle modifications
Pharmacological
Surgery (rare)
Give an example of a lifestyle modification used to treat GORD
Sitting upright after eating
When is pharmacological intervention for GORD used?
When lifestyle interventions are insufficient
Give examples of pharmacological treatments used for GORD
Antacids
H₂ antagonists
PPIs (usually the first choice)
What surgical intervention can be used to treat GORD?
Fundoplication
What is the purpose of a fundoplication?
The fundus is wrapped around the lower oesophageal sphincter to strengthen it and reduce the risk of hiatus hernia
What is acute gastritis?
Inflammation of the stomach mucosa (can be due to decreased blood flow to the mucosa)
What are the main causes of acute gastritis?
Heavy use of NSAIDS (decreases prostaglandin production and so decreases blood flow to mucosa)
Lots of alcohol
Chemotherapy
Bile reflux (bile is irritant to the stomach)
What are the symptoms of acute gastritis?
Asymptomatic
OR;
Pain, nausea, vomiting
OCCASIONALLY;
Bleeding (can be fatal)
What are the main causes of chronic gastritis?
Bacterial - H. pylori (most common)
Autoimmune - antibodies to gastric parietal cells
Chemical/reactive (the causes of acute gastritis)
How will chronic gastritis as a result of H. pylori infection present?
Asymptomatic or similar to acute gastritis
What complications can develop as a result of H. pylori infection?
Peptic ulcers, adenocarcinoma, MALT lymphoma
What can chronic gastritis with an autoimmune aetiology lead to?
Pernicious anemia
What symptoms can chronic gastritis with an autoimmune aetiology present with?
Symptoms of anaemia
Glossitis
Anorexia
Neurological symptoms
What causes susceptibility to peptic ulcers?
Unusually a deficiency in one or more mechanism that defends the mucosa from damage
What sources can damage the vulnerable mucosa?
Stomach acid
H. pylori
NSAIDS
Smoking (mainly contributes to relapse)
Stress (massive physiological stress e.g. Burns)
What are the mild symptoms of peptic ulcers?
Epigastric pain (sometimes back pain)
- Burning/gnawing pain
- Follows meal times
- Often at night (especially duodenal ulcers)
Why does epigastric pain often occur at night?
Because there is no food present and so the pH is especially low
What are the serious symptoms of peptic ulcers?
Bleeding/anaemia (from the gastroduodenal artery)
Early satiety
Weight loss
What is functional dyspepsia?
Symptoms of ulcer disease but no physical evidence of the disease or any obvious causes
How are H. pylori infections diagnosed?
Urease breath tests
How is a H. pylori infection treated?
PPI + Clarithromycin + Amoxicillin
Define peptic ulcer disease
Defects of the gastric/duodenal mucosa that extend through the muscularis mucosa
Where are peptic ulcers most commonly seen?
First part of duodenum
Where else can peptic ulcers commonly affect?
The lesser curve of the stomach
