GI Flashcards
(170 cards)
1
Q
Define Chron’s disease
A
Inflammation and tissue destruction anywhere along the GI tract
2
Q
Which pathogens can trigger Chron’s disease?
A
Mycobacterium paratuberculosis
Pseudomonas
Listeria
3
Q
How can genetics increase the risk of Chron’s disease?
A
Gene mutations in NOD2 gene cause a dysfunctional step causing unregulated inflammation
4
Q
In Chron’s disease, IFN-gamma and TNF-alpha stimulate macrophages to produce what 3 things?
A
Free radicals
Proteases
Platelet-activating factor
5
Q
How would you describe which parts of the GI tract Chron’s disease affects?
A
Whole GI tract
Patchy inflammation
Transmural
6
Q
What is most commonly affected in Chron’s?
A
Ileum and colon
7
Q
Give 3 symptoms of Chron’s
A
R lower quadrant pain
Diarrhoea and blood in stool
Malabsorption
8
Q
How would you treat Chron’s?
A
Anti-inflammatories
Abx
Immunosuppressants
9
Q
What is the most common type of IBD?
A
Ulcerative colitis
10
Q
Define ulcerative colitis
A
Inflammatory disease forming ulcers along the lumen of the colon and rectum
11
Q
Which layers of the intestinal wall are affected with ulcerative colitis?
A
Mucosa and submucosa only
12
Q
Give the two main causes of UC
A
Autoimmune
Stress/ diet
13
Q
Name the antibody responsible for attacking the body’s neutrophils in UC
A
P-ANCA
Perinuclear antineutrophil cytoplasmic antibody
14
Q
Which groups have a genetic predisposition to UC?
A
People with a family history
Young women
Caucasians
Eastern european jews
15
Q
Describe the pattern of inflammation in UC
A
Circumferential and continuous
16
Q
Give 2 main symptoms of UC
A
Pain in lower L quadrant
Sever and frequent diarrhoea (with blood)
17
Q
How might you treat UC?
A
Anti-inflammatory drugs- sulfasalazine, mesalamine
Immunosuppressant drugs- corticosteroids, azathioprine, cyclosporine
Colectomy
(Increasingly severe)
18
Q
Describe IBS
A
Recurrent abdominal pain and abnormal bowel motility
19
Q
What is visceral hypersensitivity in the context of IBS?
A
Sensory nerve endings have an abnormally strong response to stimuli (stretching)
20
Q
Which short chain-carbohydrates can trigger IBS symptoms and why?
A
Lactose and fructose as they are metabolised by GI flora, producing gas, causing pain/ cramps
21
Q
Give 2 key risk factors of IBS
A
Gastroenteritis- Norovirus/ Rotavirus
Stress
22
Q
How would you treat IBS?
A
Diet modification- Fermentable Oligosaccharides, Disaccharides, Monosaccharides and Polyols (FODMAP diet)
For constipation- stool softeners, soluble finer, osmotic laxatives
For spasms/ pain- anti-diarrhoeals, anti-muscarinic
Manage stress, anxiety, depression
23
Q
Which component of gluten binds to secretory IgA in coeliac disease?
A
Gliadin
24
Q
How is gliadin transcytosed across the cell, into the lamina propria?
A
By binding to transferrin receptor
25
Which amide is used in the conversion of gliadin to deamidated gliadin?
Tissue transglutaminase
26
How is deamidated gliadin presented to T-helper CD4+ cells?
Engulfed by macrophage and presented by MHC II
27
How do T helper CD4+ cells respond to the presentation of deamidated gliadin?
Release inflammatory cytokines: IF-gamma and TNF
B cells produce: Anti-gliadin, anti-tTG and anti-endomysial
Recruitment of killer CD8+ T cells
28
What damage occurs in the duodenum with coeliac disease?
Flattened villi- villus atrophy
Crypt hyperplasia
Lymphocyte infiltration
29
Give 3 symptoms of coeliac disease in children
Abdominal distension
Failure to thrive
Diarrhoea
30
Give 3 symptoms of coeliac disease in adults
Chronic diarrhoea
Bloating
Symptoms vary
31
How can dermatitis herpetiformis occur as a result of coeliac disease?
Circulating IgA bind to transglutaminase in the dermal papillae
Neutrophils start an inflammatory reaction causing a rash
32
What are the increased risks of refractory disease in coeliac disease?
Small bowel cancer
T-cell lymphoma
Due to chronic inflammation and immune activation
33
Describe GORD
Transient lower oesophageal sphincter relaxations
34
Give 5 risk factors of GORD
```
Weight gain
Fatty foods
Caffeine
Alcohol/ smoking
Medications
```
35
Give 4 symptoms of GORD
```
Heartburn
Cough
Hoarseness
Dysphagia
Odynophagia
```
36
How may you diagnose GORD?
Often clinical based
Endoscopy
pH testing
37
Give a key complication of GORD
Barrett's oesophagus which is a metaplasia of squamous to columnar epithelium
This can progress to cancer
38
Give 3 lifestyle modifications in the treatment of GORD
Elevated head of the bed
Diet modification
No coffee, alcohol, fats, smoking
39
Give 2 types of medications used to treat GORD
PPI
| H2 blockers
40
What is the most common type of colorectal polyp?
Adenomatous polyps
| From with a mutation in the APC gene
41
How may an adenomatous polyp become malignant?
If there is a mutation in another tumour suppressor gene e.g. K-ras and p53
42
What is familial adenomatous polyposis syndrome and what precaution may be taken?
Mutation in APC gene: many polyps
| Often colon is removed to prevent malignancy
43
What type of adenomatous polyps most often progress to malignancy?
Sessile, villous polyps
44
Give 3 types of colonic polyps
Adenomatous
Serrated polyps
Inflammatory polyps
45
How do serrated polyps form?
DNA repair genes are silenced
| Errors during DNA transcription do not get fixed, causing more mutations
46
Why do inflammatory polyps form?
Following bouts of IBD
47
Give 3 risk factors for developing colonic polyps
More cell divisions
Genetic conditions
Injury to the bowel wall- cigarette smoke, IBD, old age
48
What symptoms can occur as a result of polyps?
If they ulcerate and bleed: anaemia
| If large: can cause abdominal pain/ constipation
49
How would you diagnose colonic polyps?
Biopsy, may do a loop cauterisation
50
Which section of the oesophagus would you see an increased incidence of cancer?
Lower 1/3 and gastro-oesophageal junction
51
Give 4 causes of oesophageal cancer
Barret's oesophagus
Smoking
GO reflux
Drinking alcohol
52
Which investigations would you carry out for suspected oesophageal cancer?
Endoscopy
CT
PET scan
Endoscopic US
53
How would you treat oesophageal cancer?
2/3 cycles of chemotherapy
| Surgery
54
Give 5 risk factors of gastric cancer
```
H. Pylori infection
Male
High salt and processed food diet
Smoking
FHx
```
55
Which investigation would you carry out for suspected gastric cancer?
Loproscopy
56
Why is the prognosis for gastric cancer often poor?
Often a late diagnosis
| Few curative resections
57
How would you treat a tumour of the distal stomach?
Remove if stenosis/ bleeding
58
How would you treat a tumour of the proximal stomach?
Remove entire stomach- need vitamin B12 injections
59
Why can atelectasis occur in gastric cancer?
Alveoli collapses as the patient doesn't breathe using the diaphragm because it causes pain
60
What are the most common sites of colorectal cancer?
Rectum, sigmoid and ascending colon
61
Give 3 risk factors of colorectal cancer
Diet high in red meat and fibre
Alcohol
Smoking
62
Give 4 conditions which predispose you to colorectal cancer
Neoplastic polyps
UC
Chron's
Hereditary nonpolyposis colorectal cancer
63
How might L-sided bowel and sigmoid cancer present?
Change in bowel habit: diarrhoea/ constipation, thin stool, blood in stool
64
How might rectal cancer present?
PR bleeding, mucus, tenesmus (continuous inclination to empty the bowels), mass in PR
65
How might right sided bowel cancer present?
Weight loss
Anaemia
Mass
66
Which imaging investigations might you carry out in suspected colorectal cancer?
Liver US
CT/MRI
Barium enema- XR colon
Sigmoidoscopy/ colonoscopy
67
Which non-imaging investigations might you carry out in suspected colorectal cancer?
FBC: anaemia
| Faecal occult blood test: blood in stool
68
Describe Dukes staging for colorectal cancer
```
A= confined to bowel wall
B= Extended through bowel wall
C= Involvement of regional lymph nodes
D= Metastases
```
69
What pre-operative treatment would you give for colorectal cancer?
Abx prophylaxis
| DVT/ PE prophylaxis- LMW heparin
70
What post-operative treatment would you give for Dukes C colorectal cancer?
Adjuvant chemotherapy
71
Name and describe the function of the first 3 layers of the stomach
Epithelial layer- absorbs and secretes mucus and digestive enzymes
Lamina propria- contains blood and lymph vessels
Muscularis mucosa- smooth muscle contracts and breaks down food
72
What are the main cells found in the cardia of the stomach?
Foveolar cells secreting mucus (water and glycoproteins)
73
What are the main cells found in the fundus and body of the stomach?
Parietal cells: secrete HCl
| Chief cells: secrete pepsinogen
74
What are the main cells found in the antrum of the stomach?
G cells: secrete gastrin in response to food entering the stomach
75
What is the purpose of gastrin secretion?
Stimulates parietal cells to secrete HCl
| This stimulates growth of glands in the epithelial layer
76
What is the function of Brunner glands and where are they found?
Secrete mucous rich in bicarbonate ions into the lumen of the duodenum
Stomach and duodenal mucosa would get digested if not for mucous and bicarbonate ions which neutralise acid
77
How do prostagladins protect the stomach and duodenal mucosa?
Stimulate mucous and bicarbonate
| Vasodilate nearby blood vessels so there is more blood flowing to the stomach bringing in more bicarbonate
78
Describe and explain 3 causes of peptic ulcers
H.pylori bacteria: Gram -ve, colonise in gastric mucosa, proteases damage mucosal cells
NSAIDs: Inhibit cyclooxygenase (COX) which is an enzyme important in the synthesis of inflammatory prostagladins, leaves the mucosa susceptible to damage
Zollinger-Ellison syndrome: Gastrinoma- secretes abnormal amounts of gastrin, parietal cels release excess HCl
79
Where is the most common site for the formation of a gastric ulcer?
Lessure curvature of the antrum
80
Where is the most common site for the formation of a duodenal ulcer?
Right after the pyloric sphincter
81
Why might you see Brunner gland hypertrophy in peptic ulcer disease?
Duodenal ulcer, so glands hypertrophy to produce more mucous and protect the damaged area
82
What is the major complication with a deep peptic ulcer?
Haemorrhage into the GI tract leading to rapid blood loss and shock
83
Which two arteries are at highest risk of haemorrhaging and bleeding into the GI tract as a result of a peptic ulcer?
L gastric artery
| Gastroduodenal artery
84
Describe and explain the consequences of peptic ulcer perforation
Gastrointestinal contents can enter the peritoneal space which is usually sterile
Air can collect under the diaphragm, irritating the phrenic nerve and causing referred pain to the shoulder
85
Give a key complication of long-standing duodenal ulcers near the pyloric sphincter
So much oedema and scarring that the passage of gastric contents into the intestine is obstructed, this causes nausea and vomiting
86
Give 4 symptoms of a peptic ulcer
Epigastric pain: aching/ burning
Bloating
Belching
Vomiting
87
How might you differentiate between a gastric and duodenal ulcer?
Gastric ulcer pain increases while eating
| Duodenal ulcer pain lessens while eating
88
How would you diagnose a peptic ulcer?
Upper endoscopy into stomach and proximal duodenum
| Biopsy is done to look for malignant cells or sign of a H.pylori infection
89
How would you treat peptic ulcer disease?
If H.pylori: combination of Abx and acid lowering medications (PPIs)
Stop using NSAIDs, alcohol, tobacco and caffeine
90
Give the most common cause of appendicitis
Obstruction:
Fecalith
Undigested seeds
Lymphoid hyperplasia
91
How does the obstruction of the appendix lead to abdominal pain?
Despite the obstruction the appendix continues to secrete mucous which builds up and increases the pressure
This acts on abdominal nerve fibres causing abdominal pain
92
What are the consequences of the trapping of gut flora and bacteria in the appendix?
E.coli and bacteroides fragillis are free to multiply and so immune cells are recruited and pus accumulates, therefore there is an increase in WBC serum count
93
Give 4 symptoms of appendicitis
Nausea
Vomiting
Fever
Pain at McBurney's point (R lower quadrant)
94
How might appendicitis cause a ruptured appendix and what are the complications of this?
Increased pressure causes blood vessels to become compressed causing ischaemia
Cells producing mucous are dead and growing bacteria can invade the wall of the appendix which becomes weaker
If the appendix ruptures this may cause:
Peritonitis: pain with rebound tenderness and abdominal guarding
Periappendiceal abscess: pus and fluid forming an abscess around the appendix
95
How would you treat appendicitis?
Abscess drainage
| Appendectomy
96
Describe a volvulus
An obstruction caused by a loop in the intestines that twists around itself and surrounding mesentery
97
What is the most common type of volvulus
Sigmoid volvulus
98
How might a sigmoid volvulus occur?
During pregnancy- foetus can cause displacement and twisting of the colon
In middle aged/ elderly- chronic constipation as colon can twist around large load of stool
Abdominal adhesions- physical attachment between two parts of the abdomen serves as the pivot point
99
Why can a cecal volvulus occur in young adults?
If there is abnormal development of the abdominal mesentery, the colon can flop around freely
100
Which age group are most prone to midgut volvulus and why?
Babies/ small children
As a result of abnormal intestinal development in foetuses: If there is malrotation at 12 weeks and the cecum and appendix stay on the upper R side
This often causes later twisting of the small intestine
101
What are the risks if the mesentery is tightly twisted in a volvulus?
Infarction leading to bloating, constipation, severe pain and bloody stool
The intestinal wall can break down, releasing bacteria and causing sepsis and cardiovascular collapse
102
How would you diagnose a volvulus?
Abdominal XR: looks like a coffee bean
| Barium enema: shows bird's beak shape (enlarged at one end, tapered at the other)
103
How would you treat a volvulus?
Sigmoidoscopy: if looks normal and pink, untwist tubes and decompress colon to relieve pressure
104
When would you require immediate surgery on a volvulus and what would this involve?
If bowel is severely twisted
If blood supply is cut off
Involves the untwisting of bowel and attaching it to the abdominal wall
105
What is a bowel intussusception?
Where the intestine folds in on itself, usually when the ileum folds into the cecum
106
Give 2 common causes of intussusception in adults
Polyps
Tumour
(Contracting intestines can grab the leading edge and pull it ahead)
107
What is the main cause of intussusception in babies?
Leading edge is often lymphoid hyperplasia
| Payers patches: many tiny lymph nodes common in the ileum which enlarge to fight off infection- form a lead point
108
What is Meckel's diverticulum and how can it cause intussusception?
Out-pouching of GI tissue
Usually sticks out into the peritoneal cavity
Occasionally can invert and stick back into the intestine, drawing the ileum into the cecum
109
Give 3 risk factors for intussusception
Having previously had an intussusception
Having a sibling with an intussusception
Intestinal malrotation
110
Describe the nature of the pain with intussusception
Intermittent abdominal pain
Worse with peristalsis
May cause child to guard abdomen
May draw knees to chest
111
Give 3 signs/ symptoms of intussusception
Abdominal pain
Vomiting
Hard, sausage-lek mass in abdomen
112
Explain the complications as a result of the pressure exerted on the walls of the trapped bowel due to intussusception?
Squeezes blood vessels shut causing ischaemia/ infarction
Intestinal mucosa, blood and mucus enters the gut
If there is intestinal tearing, there is release of bacteria causing sepsis/ fever
113
How can an intussusception cause a volvulus?
It can prevent food/ fluid passing, this large mass acts as a pivot point causing the intestine to twist
114
How would you diagnose an intussusception?
In children: may be felt during a DRE
Definite diagnosis requires imaging:
US, X-ray, CT
'Bulls-eye' telescoped inside
115
How would you treat an intussusception?
```
Barium/ air enema can unfold an intussusception
Surgery may be necessary:
Telescoped intestine is freed
Obstruction is cleared
Dead tissue is removed
```
116
Give the 4 layers of the bowel wall
Serosa
Muscle
Submucosa
Mucosa
117
Describe the difference between a true and false diverticula
True: involves all layers
| False(pseudo): only mucosa and submucosa poke through muscle layer (muscle layer is not included)
118
Where do most diverticula form and why?
Most form in the sigmoid colon as it has the smallest lumen diameter and therefore highest pressure
Also at weak spots where a blood vessel traverses the muscle layer, vessel is more likely to rupture causing rectal bleeding
119
Give 3 risk factors for diverticula formation
Low fibre- constipation
Fatty foods and red meat
Marfan syndrome and Ehlers-Danlos
120
How can diverticulitis occur?
Lodged faecalith
| Erosion from high pressure
121
Where would pain be felt with diverticulitis?
L lower quadrant
122
Why is diverticulitis not associated with bleeding?
Blood vessels are scarred from inflammation
123
What is the key complication if diverticula rupture?
Fistula formation e.g. a colovesicular fistula (colon to bladder) causing air/ stool in the urine
124
How would you treat diverticulitis?
Abx- to limit bacterial growth
High fibre diet
Surgical removal
125
Give 5 examples of true bowel obstructions
```
Volvulus
Adhesion
Tumour
Intussusception
Hernia
```
126
Give 3 examples of bowel pseudo-obstructions
Myopathy- no peristaltic contractions occur
Neuropathy- no innervation of the bowel smooth muscle
Hirschsprung's disease
127
Describe Hirschsprung's disease
Rare congenital condition where nerves are missing at the distal end of the colon
Therefore the bowel cannot relax to pass stool, this is corrected by surgery
128
How would you differentiate between large and small bowel obstruction?
Vomiting: Early= small, late= large
Constipation: Early= large, late= small
More distal the obstruction, more distension
129
Which investigations would you carry out for suspected bowel obstruction?
Inflammatory markers, lactate: ischaemia
| CT scan: give oral and IV contrast
130
When would you not give contrast to a patient with suspected bowel obstruction and why?
If the patient had a perforation as the contrast could enter the peritoneum
131
Give 4 symptoms of gastritis
Indigestion
Gnawing/ burning stomach pain
Nausea and vomiting
Feeling full after eating
132
Give 3 signs/ symptoms of erosive gastritis
Stomach is exposed to acid:
Pain
Bleeding
Stomach ulcer
133
How would you diagnose gastritis?
Stool test
Breath test for H. pylori infection
Endoscopy
Barium swallow
134
Give 5 possible causes of gastritis
```
H. pylori
Excessive cocaine/ alcohol use
NSAIDs
Stressful event
Autoimmune reaction
```
135
How would you treat gastritis?
Antacids
Histamine 2 blockers (H2 blockers): Ranitidine
PPI: Omeprazole
If H. pylori : Abx
136
Give the components of the submucosa and muscular propria of the small bowel wall
Submucosa: connective tissue with collagen, elastin and glands/ vessels and Meissner plexus
Muscularis propria: two layers of smooth muscle + Myenteric plexus
137
Describe the process of ischaemic injury and reperfusion injury in small bowel ischaemia
Ischaemic injury: production of ROS, can damage DNA, RNA and proteins
Reperfusion: increase in oxygen and oxidative stress, increases ROS which attracts immune species
Immune cells remove dead/ damaged cells and release cytokines
138
How can sepsis occur as a result of small bowel ischaemia?
Food lingers in the ileum and doesn't get pushed along
Break in the epithelial lining allows bacteria into the peritoneal space, lymphatics and blood vessels
Vessels get leaky leading to septic shock
139
Give 5 examples of occlusive bowel obstruction
```
Hernia
Embolus
Tumour
Volvulus
Intussusception
```
140
Give 3 examples of non-occlusive bowel obstruction
Low CO2
Hypovolemia
Mucosal infarcts
141
Give a symptom of bowel ischaemia and 4 symptoms of infarction
```
Ischaemia:
Severe abdominal pain
Infarction:
Vomiting
Bloody diarrhoea
Distended abdomen
Loss of bowel sounds
```
142
Give 3 symptoms of sepsis
Fever
Decreased BP
Increased HR and RR
143
How would you diagnose small bowel ischaemia?
```
Abdo CT:
Bowel dilation and bowel thickening
Intestinal pneumatosis
CT angiography
Lad studies:
Raised WBC
Metabolic acidosis
```
144
How would you treat small bowel ischaemia?
```
Increase fluid
Manage pain
Abx
Surgery to reestablish blood flow
Thrombolytic enzymes
Surgical resection
```
145
Describe Mallory-Weiss syndrome
Longitudinal tears near the gastro-oesophageal junction
146
Give 4 associated causes of Mallory-Weiss syndrome
Vomiting
Retching
Coughing
Straining
147
How would Mallory-Weiss syndrome present?
Haematemesis
Melena
Dizziness
Abdominal pain
148
How would you diagnose Mallory-Weiss syndrome?
Endoscopy
149
How would you treat Mallory-Weiss syndrome?
Cauterisation, epinephrine injection, haemoclipping, band ligation
Embolisation
Surgery
150
Describe haemorrhoids
Swellings containing enlarged blood vessels found in the rectum and anus
151
Give 2 causes of haemorrhoids
Prolonged constipation
| Chronic diarrhoea
152
Give 6 risk factors for haemorrhoids
```
Obesity
Age
Pregnancy
FHx
Lifting heavy objects
Persistent cough/ repeated vomiting
```
153
Give 5 symptoms of haemorrhoids
```
Bleeding after passing a stool
Itchy anus
Lump outside anus
Mucus discharge after passing a stool
Soreness, redness and swelling
```
154
Give 4 lifestyle changes for a patient with haemorrhoids
Losing weight
Increase amount of fibre in diet
Drink plenty of fluid
Avoid medication causing constipation: painkillers containing codeine
155
Describe an anal fistula
Chronic, abnormal communication between epithelial surface of the anal canal and the perianal skin
156
How might an anal fistula form?
If the outlet of the anal glands becomes blocked, an abscess can form which can eventually extend to the skin surface
157
Give 5 symptoms of an anal fistula
```
Skin irritation around the anus
Constant throbbing pain
Smelly discharge proximal to anus
Pus/ blood in faeces
Swelling/ redness around anus
Fever (if abscess)
Bowel incontinence
```
158
How would you diagnose an anal fistula?
DRE
Protoscopy
US, MRI, CT
159
Give 4 causes, other than an anal abscess, of an anal fistula
Caron's
Diverticulitis
TB/ HIV
Complication of surgery
160
Describe an anal fissure
Tear or ulcer that develops in the lining of the anal canal
161
Give 2 symptoms of an anal fissure
Sharp pain when you pass stools, often followed by a deep burning pain
Bleeding when passing stools
162
Give 5 causes of an anal fissure
```
STI
Constipation
Persistent diarrhoea
IBD
Pregnancy/ childbirth
```
163
Give 4 lifestyle changes for someone with an anal fissure
High fibre diet
Increase fluids
Not ignoring the urge to pass stools
Exercise regularly
164
Describe a perianal abscess
Abscess adjacent to the anus, arising from an infection at one of the anal sinuses
165
Give 3 bacterial causes of a perianal abscess
E. coli
Staph
MRSA
166
Give 5 symptoms of a perianal abscess
```
Pain in the perianal area
Constipation
Drainage from the rectum
Fever
Chills
Palpable mass near anus
```
167
Give 3 risk factors for developing a perianal abscess
Chron's
Diabetes
Chronic corticosteroid treatment
168
Describe a pilonidal sinus and what can happen if this becomes infected
Small hole or tunnel in the skin at the top of the buttocks, an infection of this sinus will cause pain, swelling and a pus-filled abscess can develop
169
Give the key cause of a pilonidal sinus developing
A skin problem, pressure/ friction may cause hair between the buttocks to be pushed inwards
170
How would you treat an infected pilonidal sinus?
Abx
Painkillers
Drainage of the sinus
