1
Q
What are the two main causes of small bowel ischaemia?
A
- Mesenteric artery occulsion
- Non-occlusive perfusion insufficiency
2
Q
Why may the mesenteric artery become occluded?
A
- Atherosclerosis
- Thromboembolism (from AF for example)
3
Q
What are some causes for non-occlusive perfusion insufficiency of the small bowel?
A
- Shock
- Strangulation - obstructs venous return
- Drugs - cocaine
- Hyperviscosity
4
Q
Which area of the small bowel is most affected by ischaemia?
A
Mucosa
(it is the most metabolically active tissue)
5
Q
As time of ischaemia increases in the small bowel, what are the consequences?
A
Ischaemia worsens and deepens
Gangrene may eventually develop
6
Q
What is the difference between the outcomes of:
a) Mucosal infarct
b) Mural infarct
c) Transmural infarct
A
a) Regeneration - mucosal integrity is restored
b) Repair and regeneration - a fibrous stricture forms
c) Gangrene - death occurs unless this part of the small bowel is resected
7
Q
What is the danger of gangrene in the small bowel?
A
The small bowel will perforate, cause peritonitis, sepsis and even death
8
Q
Which type of tumour, primary or secondary, are more common in the small bowel?
A
Secondary
(primary are very rare)
9
Q
Which types of secondary tumours are common in the small bowel?
A
Metastases from:
- Ovaries
- Colon
- Stomach
10
Q
Which types of primary tumours are likely to affect the small bowel?
A
- Lymphomas
- Carcinoid tumours
- Carcinomas
11
Q
Which conditions are associated with carcinoma of the small bowel?
A
- Crohn’s disease
- Coeliac disease
12
Q
Where will a carcinoma of the small bowel usually metastasise to?
A
- Lymph nodes
- Liver
13
Q
What may be the clinical signs of appendicitis?
A
- Vomiting
- Abdominal pain
- RIF tenderness
- Increased WCC
14
Q
What is the aetiology of appendicitis?
A
- Idiopathic
- Faecoliths
- Lymphoid hyperplasia
- Parasites
- Tumours
15
Q
What are faecoliths?
A
Small hard lumps of faeces which can commonly enter and inflame the appendix leading to acute appendicitis
They are often the result of dehydration
16
Q
What are the features of an appendix during acute appendicitis?
A
- Acute inflammation - involving the muscle coat
- Mucosal ulceration
- Serosal congestion
- Pus in the lumen
17
Q
What happens to the muscular wall in appendicitis?
A
It thickens
18
Q
What are the complications of appendicitis?
A
- Peritonitis
- Rupture
- Abscess
- Fistula
- Sepsis and liver abscess
19
Q
Coeliac disease is due to an abnormal reaction to what?
A
Gliadin - a component of gluten
20
Q
Coeliac disease is mediated by which cell type?
A
T-cells
(intraepithelial lymphocytes)
21
Q
How is the mucosa in the small bowel affected during Coeliac disease?
A
The mucosal surface flattens and complete villus atrophy occurs
22
Q
Which antibodies will be found in a sufferer of Coeliac disease?
A
- Anti-TTG
- Anti-endomesial
- Anti-gliadin
23
Q
Why may coeliac disease often lead to anaemia?
A
There is poor absorption of iron, vitamin B12 and folate from the terminal ileum
24
Q
Why are gallstones a potential complication of Coeliac disease?
A
There is reduced intestinal hormone production which reduces pancreatic secretion which in turn affects bile flow
25
Which inflammatory oesophageal conditions may be acute?
* Chemical ingestion
* Infection in immunocompromised patients e.g. candida, herpes, cytomegalovirus, HIV, chemotherapy
26
Which inflammatory cells are often present during reflux disease in the oesophagus?
Eosinophils
27
Why may reflux oesophagitis even arise?
* Defective sphincter mechanism
* Hiatus hernia
28
What are the potential complications of oesophagitis?
* Ulcers - when a physical prtective barrier cannot be made quickly enough
* Strictures and fibrosis - due to the healing process from continued injury
* Barrett's oesophagus - replacement of stratified squamous epithelium by columnar epithelium which include more mucous cells for protection
29
What is Barrett's oesophagus?
The change of epithelium in the oesophagus from stratified squamous epithelium to columnar epithelium
This means more mucous cells are present for protection
30
What is allergic oesophagitis?
Eosinophilic inflammation in the oesophagus due to allergy
The oesophagus becomes corrugated and feline-like
31
Which age and gender are most likely to suffer from allergic oesophagitis?
Young males
| (often have asthma)
32
Which rare oesophageal tumour is associated with HPV?
Squamous papilloma
33
Which tumours are malignant in the oesophagus?
Squamous cell carcinomas
Adenocarcinomas
34
Squamous cell carcinomas are related to what?
* Vitamin A or zinc deficiency
* Tannic acid or strong tea
* Smoking and alcohol
* HPV
* Oesophagitis
* Genetic
35
Which tumour type is associated with dysphagia?
Squamous cell carcinoma
or
Adenocarcinoma
36
Which tumour eventually arises from Barrett's oesophagus assuming dysplasia eventually does occur and progress?
Adenocarcinoma
37
Where in the oesophagus does an adenocarcinoma affect?
Bottom 1/3rd of oesophagus
38
Carcinomas of the oesophagus can spread via metastses to which other locations in the body?
* Direct invasion
* Lymphatic permeation
* Vascular invasion
39
What is a Mallory-Weiss tear?
A tear in the oesophagus 2cm above the Z-line
It is cause by severe and prolonged vomiting
It will result in bleedign and haematemesis
40
What is the term given to dilated veins in the distal oesophagus?
Oesophageal varices
41
What is the main cause of oesophageal varices?
Increased portal venous pressure due to chronic liver disease
42
Describe the TNM staging system for tumours
T - Greatest diameter of tumour an invasion
N - Lymph node status (how many are affected)
M - Metastases
43
Inflammatory bowel disease emcompasses which two conditions?
1. Crohn's disease
2. Ulcerative colitis
44
What is Crohn's disease?
Chronic inflammation and ulcering of the GI tract anywhere from the mouth to the anus yet most commonly in the terminal ileum and colon
45
How will Crohn's disease present clinically?
* Abdominal pain
* Small bowel obstruction
* Diarrhoea
* Bleeding PR
* Anaemia
* Weight loss
46
Which investigations should e taken for a patient with suspected Crohn's disease?
* Endoscopy
* Mucosal biopsy
47
In relation to the distribution of Crohn's disease, how would it be described?
Continuous, or patchy?
Patchy and segmental
48
How does the body often respond to the damage caused by Crohn's disease in the terminal ileum for example?
1. Stricturing of the terminal ileum
2. Thickening of the bowel wall
3. Fat wrapping (from greater omentum)
49
Which inflammatory bowel disease produced cobblestoning of the mucosa?
Crohn's disease
50
Deep fissures into the mucosa are associated with which IBD?
Crohn's
51
Transmural inflammation occurs with which IBD?
Crohn's
52
What are the main complications of Crohn's disease?
* Malabsorption - latrogenic (short bowel syndrome) due to repeated resections and removal
* Hypoproteinemia, vitami deficiency, anaemia
* Gallstones
* Fistulas (colic, vaginal, blind loop syndrome)
* Anal disease - fissures, abscesses, sinuses
* Toxic megacolon - very rare
* Malignancy
53
Crohn's disease is most common in which group of people?
Caucasians
54
What is thought to cause Crohn's disease?
* Genetic defects - frameshift mutation in the NOD2 gene
* Environmental factors
55
Whih environmental triggers affect Crohn's disease?
* Smoking
* Infectious agents
* Vasculitis
* Sterile environment theory
56
Why is Crohn's not an autoimmune condition?
It involves an unregulated and out of control immune response to a pathogen
There is persistant activation of T cells which leads to damage
57
What is ulcerative colitis?
Chronic inflammation confined to the colon and rectum
58
Which layers of the small intestine wall are affected in ulcerative colitis?
Mucosal and submucosa
59
What is the most common inflammatory bowel disease?
Ulcerative colitis
60
Are patients diagnosed with UC generally old or young?
Young
61
Is UC a patchy or continous condition along the colon and rectum?
Continuous
62
What is the clinical presentation of UC?
Diarrhoea, mucus and blood PR
63
Which inflammatory bowel disease is associated with periods of exacerbation and periods of remission?
UC
64
Which investigations ae required for a patient with suspected UC?
* Endoscopy
* Mucosal biopsy
65
How are the crypts in the small intestine affected in UC?
They become irregularly shaped and branching
66
If a patient with UC fails to respond to corticosteroids, what is the other option for treatment?
Subtotal colectomy
(removal of colon leaving rectum behind)
67
How do the ulcers in UC differ from those seem in Crohn's?
They are broader based
They do not permeate as deep into the small bowel wall
68
In which IBD are granulomas formed?
Crohn's
69
Why is colorectal cancer a complication of UC?
Chronic inflammation leads to dysplasia and then to carcinoma
70
How can UC affect electrolyte balance?
It can cause hypokalaemia
71
How may UC present as a sign on the skin?
Pyoderma gangrenosum
Erythema nodosum
72
How may UC affect the eye?
Uveitis
73
Which environmental factor that causes exacerbation of Crohn's does not affect UC?
Smoking
74
Which IBD involves transmural inflammation?
Crohn's disease
75
In which IBD is cancer risk higher?
UC
76
In which IBD are fistulas more common?
Crohn's
77
What are the three causes of chronic gastritis?
1. Autoimmune
2. Bacterial
3. Chemical
78
Which bacterial species is respoinsible for causing gastritis?
Helicobacter pylori
79
What is the cause of gastritis in autoimmune gastritis?
Anti-parietal and anti-intrinsic factor antibodies
80
What occurs in the stomach in response to autoimmune gastritis?
Atrophy
Intestinal metaplasia
81
Why does pernicious anaemia often occur with autoimmune gastritis?
Anti-intrinsic factor antibodies bind to instrinsic factor preventing vitamin B12 from being absorbed
This happens because intrinsic factor must bing to vitamin B12 in order to be absorbed
82
How do red blood cells present in autoimmune gastritis?
Macrocytic
| (lack of vitamin B12)
83
What is the most common cause of chronic gastritis?
H. pylori associated gastritis
84
Where in the stomach wall does H. pylori inhabit?
The area between the epithelial cell surface and the mucous barrier
85
H. pylori infection increases the risk of which 4 main things?
1. Gastric ulcer
2. Duodenal ulcer
3. Gastric carcinoma
4. Gastric lymphoma
86
What is the cause of chemical gastritis? (3)
1. NSAIDS
2. Alcohol
3. Bile reflux
87
What is peptic ulceration?
A breach of the gastrointestinal mucosa as a result of acid and pepsin attack
88
Where are chronic peptic ulcers likely to develop?
* Duodenum (1st part)
* Stomach
* Gastro-oesophageal junction
* Stomal area (when a patient has a stoma bag)
89
Why can excess acid in the duodenum eventually allow for H. pylori infection there?
The acid causes metaplasia of the duodenal mucosa causing it to become more like gastric mucosa and therefore be habitable for H. pylori
90
What allows for chronic peptic ulcers to occur? (2)
1. Increased acid
2. Poor mucosal defence
91
What are the complications of a peptic ulcer?
* Perforation
* Penetration
* Haemorrhage
* Stenosis
* Intractable pain
92
What is crucial for the chronic inflammation seen with H. pylori infection?
IL-8
93
What is the term given to benign gastric tumours?
Polyps
94
What are the two malignant gastric tumours?
* Carcinoma (adenocarcinoma)
* Lymphoma
95
Why does H. pylori increase risk for gastric adenocarcinoma?
It causes chronic gastritis
This leads to intestinal metaplasia, dysplasia and eventually carcinoma
96
What is Lynch syndrome?
Lynch syndrome, often called hereditary nonpolyposis colorectal cancer(HNPCC), is an inherited disorder that increases the risk of many types of cancer - mainly colorectal cancer
97
What is Menetrier's disease?
A rare, acquired, premalignant disease of the stomach
It is characterised by massive gastric folds, excessive mucous production (with resultant protein loss), and little or no acid production.
The condition is associated with excessive secretion of TGF-α
98
What are the two types of gastric adenocarcinoma and what is the differnece between the two?
1. Intestinal type - exophytic - grows outwards
2. Diffuse type - expands and infiltrates the stomach wall
99
Of the two types of gastric adenocarcinoma, which has better prognosis?
Intestinal type
100
Where can gastric adenocarcinomas spread?
* Local - other organs, peritoneal cavity, ovaries
* Lymph nodes
* Haematogenous - to the liver
101
What is another name gastric lymphoma?
Maltoma
102
Gastric lyphoma is associated with what?
H. pylori infection
103
Which type of tissue is associated with gastric lymphoma?
Mucosa associated lymphoid tissue (MALT)
104
Acute liver failure may manifest as jaundice. What are some causes for this?
Viruses
Alcohol
Drugs
Bile duct obstruction
105
If a patient has acute liver failure which three main ways can they progress?
1. Complete recovery
2. Chronic liver disease
3. Death
106
What are the two different forms of bilrubin in the body?
1. Conjugated
2. Unconjugated
107
What is conjugated bilirubin?
This is synthesised by the liver
Bilirubin is conjugated with glucuronic acis by enzyme action
This type of bilirubin is then metabolised further and the products are passed out of the body in faeces and urine
108
What is unconjugated bilirubin?
This is bilirubin that is yet to be conjugated by the liver
109
What are the three types of jaundice?
1. Pre-hepatic
2. Hepatic
3. Post-hepatic
110
What is pre-hepatic jaundice?
Caused by haemolysis of all causes such as haemolytic anaemias resulting in large amounts of unconjugated bilirubin being produced
111
What causes hepatic jaundice?
Any injury to the liver cells affecting their ability to process biirubin
112
What are some causes for hepatic jaundice?
* Acute liver failure (viruses, drugs, alcohol)
* Alcoholic hepatitis
* Cirrhosis
* Bile duct loss (atresia, PBC, PSC)
* Pregancy
113
What is post hepatic jaundice?
The liver processes bilirubin fine, but bile cannot escape into the bowel due to ostruction
114
Give some causes for post-hepatic jaundice
* Congenital biliary atresia
* Gallstones block the common bile duct
* Strictures of the common bile duct
* Tumours
115
What is the final common end point for liver disease?
Cirrhosis
116
What are some complications of cirrhosis?
* Portal hypertension - oesophageal varices, caput medusa, haemorrhoids
* Ascities
* Liver failure
117
A cirrhosed liver is more susceptible to what?
Hepatocellular carcinoma
| (or other malignancies)
118
What is NASH?
Non-alcoholic steatohepatitis
A pathologically identical disease to alcoholic liver disease, yet patients do not drink
119
Which type of patients will NASH occur in?
Diabetes
Obesity
Hyperlipidaemia
120
How is hepatitis A spread?
Faecal/oral
121
How is hepatitis B spread?
Blood
Sexually
Vertically (mother to child)
122
What causes the liver damage in hepatitis B?
Antiviral immune response
123
How is hepatitits C spread?
Blood
Potentially sexually
124
Which type of hepatitis virus is most likely to become chronic?
Hepatitis C
125
Which type of necrosis is associated with hepatitis, most specifically viral?
Piecemeal (interface) necrosis
Necrosis occurs in fragments
Refers specifically to a loss and degeneration of hepatocytes at the lobular-portal-interface, producing a moth-eaten irregular appearance.
It is associated with a lymphocytic infiltrate into the adjacent parenchyma.
126
What is primary biliary cholangitis?
Autoimmune disease associated with autoantibodies to mitochondria
It results in slow destruction of small bile ducts in the liver over time causing bile and other toxins to build up
127
Which gender is most likely to develop PBC?
Females
128
What are the outcomes if PBC is left untreated?
* Cholestasis
* Inflammation
* Fibrosis
* Cirrhosis
129
Autoimmune hepatitis is more common in which gender?
Females
130
What is primary sclerosing cholangitis?
A chronic inflammatory process affecting intra and extra hepatic bile ducts
This impedes bile flow and can lead to fibrosis
131
Primary sclerosing cholangitis is more common in which gender?
Males
132
Primary sclerosing cholangitis is associated with which other GI condition?
Ulcerative colitis
133
What is the term given to too much iron within the liver?
Haemochromatosis
134
What are the two types of haemochromatosis?
Primary - inherited
Secondary - to other factors
135
Why is primary haemochromatosis bad?
There is excess iron absorption from the intestine
Iron is depositied in the liver
Portal connective tissue is eventually affected by these depositis
Cirrhosis wil develop and predisposed to carcinoma
136
As well as cirrhosis, what else can primary haemochromatosis cause?
Diabetes
Cardiac failure
Impotence
137
Which stain confirms the presence of iron in the liver?
Perls stain
138
What is Wilson's disease?
Inherited autosomal recessive condition affecting copper metabolism
Copper accumulates in the liver and brain
Chronic hepatitis and neurological deterioration can be caused
139
What is a clinical sign of Wilson's disease in relation to the eyes?
Kayser-Fleischer rings at the corneal limbus
140
What is alpha-1-antitrypsin deficiency and what does it cause?
Inherited autsomal recessive disorder of the production of an enzyme inhibitor
Cytoplasmic globules of unsecreted protein build up
This can cause cirrhosis and emphysema
141
What are the two different types of tumours which can arise in the liver?
1. Primary
2. Secondary
142
What are the two most common primary tumours of the liver?
1. Hepatocellular adenoma
2. Hepatocellular carcinoma
143
Where can secondary tumours of the liver originally arise?
Colon, pancreas, stomach, breast, lung etc.
144
Hepatocellular adenoma is a ________ tumour most common in \_\_\_\_\_\_\_\_\_\_
Benign
Females
145
Hepatocellular carcinoma is associated with what?
HBV
HCV
Cirrhosis
146
What is cholelithiasis?
The development of gallstones
147
What are the three main bile components?
1. Bilirubin
2. Cholesterol
3. Bile salts
148
When will gallstones form?
When there is an imbalance between the ratio of cholesterol to bile salts disrupting micelle formation
(too much cholesterol causes free crystallisation on micelle surface)
149
Pigment stones in the gallbladder are caused by what?
Excess bilirubin
| (from haemolytic anaemia for example)
150
What is a complication of a fistula forming between the gallbladder and the small bowel?
Gallstone ileus
(gallstones can pass into the small intestines and become trapped in the ileocaecal valve)
151
What is cholecystitis?
Inflammation of the gallbladder
152
Rupture, peritonitis, septicaemia and death are complcications mainly associated with acute or chonic cholecystitis?
Acute
153
Gallstones are formed with which type of cholecystitis, acute or chronic?
Chronic
154
Which type of cancer is associated with the gallbladder?
Adenocarcinoma
| (this is rare)
155
Cancer of the bile ducts is called what?
Cholangiocarcinoma
156
Cholangiocarcinoma is associated with which other GI conditions?
Ulcerative colitis
Primary sclerosing colitis
157
Which condition will all sufferers get if they have their pancreas removed?
Diabetes
158
When the pancreas is necrosed which enzyme is secreted?
Amylase
159
What is the biggest cause of chronic pancreatitis?
Alcohol
160
The inflammation and fibrosis found in chonic pancreatitis can mimic which other condition?
Cancer
161
Why can small cancers of the pancreas be as high as stage 4 very quickly?
The pancreas is a very intimate organ so will spread very easily
162
The oesophagus is lined with which type of epithelium?
Stratified squamous epithelium
163
What are some complications of chronic oesophagitis?
Ulceration leading to stricture and fibrosis
(Barrett's oesophagus may also occur)
164
What is Barrett's oesophagus?
Stratified squamous epithelium is replaced by columnar epithelium
165
Allergic oesophagitis is mediated by which cell type?
Eosinophils
166
Which benign tumour will be found in the oesophagus?
Squamous papilloma
167
Which tumour(s) associated with the oesophagus is HPV related?
Squamous papilloma
Squamous cell carcinoma
168
Oesophageal varices are usually formed as a result of what?
Portal hypertension
| (often due to liver disease)
The Gastrointestinal System
flashcards
Decks in class (27)
# Cards
-
Anatomy - Theory224
-
Microbiology and Infection100
-
Liver Disease52
-
Pathology168
-
Liver Function Tests32
-
Liver Lesions32
-
Pharmacology of the GI Tract62
-
GI Bleeding11
-
The Endoscope7
-
GORD, Dyspepsia and Ulcers58
-
Intestinal Failure18
-
Hepatitis40
-
Biliary Tract Disease14
-
Antibiotic Resistance and Stewardship10
-
Pancreatitis and Pancreatic Tumours41
-
Inflammatory Bowel Disease21
-
Biochemistry127
-
Hernias42
-
Benign Conditions of the Large Bowel21
-
Overview of the Physiology of the GI Tract40
-
Colorectal Cancer0
-
Malnutrition, Malabsorption, Dietary and Weight Guidelines0
-
Physiology and Pharmacology of Saliva and Gastric Secretions0
-
Physiology of Digestion and Absorption0
-
Immunology of the GI Tract0
-
Histology of the GI Tract0
-
Tropical Gastroenterology0
