GI Flashcards
(198 cards)
1
Q
1 What cells are responsible for vitamin B12 secretion?
A
Parietal cells of the stomach
2
Q
1 Where does the majority of water absorption from the gastrointestinal tract occur?
A
Ileum
3
Q
1 What are retroperitoneal viscera?
A
Organs which only have their anterior surface in contact with the peritoneum
4
Q
1 What is mesentery?
A
Double fold of peritoneum that supports intra-peritoneal viscera
5
Q
1 What’s Barrett’s oesophagus?
A
Dysplastic change from stratified squamous epithelium to columnar occurring in oesophagus in response so reflux of acid from the lower oesophageal sphincter.
6
Q
1 What would you see on an X-ray of a patient with a perforated gastric ulcer?
A
Gas in peritoneal cavity
7
Q
1 What drugs would you use to treat a gastric ulcer?
A
Proton pump inhibitor or H2 antagonist
8
Q
1 Which tends to bleed more a gastric or duodenal ulcer?
A
Duodenal
9
Q
1 What is the most common source of liver tumours?
A
Metastasis from colo-rectal cancer
10
Q
1 What are the 2 most common causes of acute pancreatitis?
A
Gallstones and excess alcohol consumption
11
Q
1 Which vitamin does the liver help synthesize?
A
Vitamin D
12
Q
1 Why does an ileostomy look different from a colostomy?
A
Ileostomy is spouted to protect the skin from irritant alkaline contents of ileum, colostomy is flat.
13
Q
1 What is the main function of the large intestines?
A
Water absorption
14
Q
1 Name 2 inflammatory diseases that effect the large bowel
A
Crohn’s disease and ulcerative colitis
15
Q
1 List 3 potential consequences of diverticula disease
A
They can bleed, become inflamed or become infected
16
Q
1 Which part of the large intestine is most susceptible to volvulus?
A
Sigmoid colon
17
Q
2 What embryological structures are the greater and lesser omenta derived from?
A
Greater omentum from dorsal mesentry
Lesser omentum from ventral mesentry
18
Q
2 Where exactly do the greater and lesser sacs of the abdominal cavity communicate?
A
Via the epiploeic foramen / foramen of Winslow
This is located between the liver and duodenum, under the free edge of the lesser omentum.
19
Q
2 What is the embryonic vitelline duct and why is its persistence a problem?
A
Tube connecting developing gut tube to yolk sac. If patent will see intermittent discharge of enteric contents.
20
Q
2 What are the boundaries of the fore- mid- and hind- gut derived structures on the GIT?
A
Bile duct opening into duodenum
2/3 along transverse colon
21
Q
2 What divides the respiratory diverticulum form the developing embryonic gut tube?
A
The tracheoesphageal septum
22
Q
2 Where are the cell bodies of the sympathetic nervous system located?
A
Spinal cord of T5 to L3
23
Q
2 What are the 2 main plexuses of the enteric nervous system? Where are they located?
A
Meissner’s / submucosal - submucosa
Auerbach’s / myenteric - between circular and longitudinal muscle of gut tube
24
Q
2 What’s Hirschsprung’s disease?
A
Lack of myenteric and submucosal plexuses cauisng functional obstruction.
25
2 How is water absorbed in the gut?
Mostly passively, following nutrients after meals or Na+ and Cl- otherwise.
Desiccation of stool in colon, water follows Na+ which is absorbed via ENaC.
26
2 How is the S intestine epithelium adapted to facilitate absorption?
Plicae circulares - permanent folds; villi and microvilli all increase surface area available for absorption.
27
2 Name 4 hormones secreted by the GIT and which cells secrete them
Gastrin - G cells of stomach
CCK - I cells of duodenum and jejunum
Secretin - S cells of duodenum
Gastric Inhibitory Polypeptide - duodenum and jejunum
28
2 Which 2 parasympathetic nerves supply the GIT?
Vagus nerve
| Pelvic splanchnic nerves (S2-4)
29
2 Describe roots of the sympathetic innervation of the gut
3 Pre-synaptic splanchnic nerves:
Greater T5-9
Lesser T10-11
Least T12
30
2 Which hormone is produced in response to sugars, amino acids and fatty acids in the S intestine?
Gastric Inhibitory Polypeptide
31
2 Which gut hormone reduces gastric acid secretion?
Secretin
32
2 Which hormone/s stimulate/s the exocrine pancreas?
Cholecystokinin (enzymes / acinar cells) and Secretin (bicarbonate)
33
3 What type of epithelium lines most of the gastrointestinal tract?
Columnar (stratified squamous in oesophagus & distal anus)
34
3 What's in the lamina propria of the gut mucosa?
Lymphoid nodules; macrophages; antibodies, mainly IgA
35
3 How does the muscularis mucosa of the gut support the innate immune system?
Contractions of the muscularus mucosa help keep contents of gastric crypts dynamic thus avoiding the formation of areas of stagnancy which would be prone to microbial growth.
36
3 What do paneth cells do?
Secrete antibacterial proteins to protect the adjacent stem cells (in the bottom of the intestinal crypts)
37
3 What is the arcuate line an important landmark of?
Point at which epigastric vessels penetrate abdominal wall. (Arcuate line = The lower limit of the posterior layer of the rectus sheath)
38
3 Why can a Meckel's diverticulum cause problems?
Can contain ectopic gastric or pancreatic tissue and can also become inflammed due to stasis.
39
3 How are gastroschisis and omphalocoele / exomphalos difference in appearence?
Gastroschisis - just gut tube, no covering
| Omphalocoele / exomphalos - gut is within aminion of umbilical cord
40
3 What is the embryological origin of the pectinate line of the anal canal?
Epithelium of anal canal has 2 origins:
| endoderm proximally and distally, ectoderm. These 2 areas are separated by the pectinate line.
41
3 Describe the innervation of the anal canal.
Above pectinate line - S2,3,4 pelvic splanchics only sensation possible is stretch.
Below - S2,3,4 pudenal n; touch, temperature and pain can also be perceived
42
4 Anatomically, where do most hernias of the abdominal wall occur?
Inguinal hernias are the most common abdominal wall hernias and leave the abdominal cavity in the inguinal region.
43
4 What is the anatomical postion of direct inguinal hernias?
Area of potential weakness in abdo wall called Hesselbach’s triangle (borders are rectus abdominis, inf epigastric artery and inguinal ligament).
44
4 Why would you be concerned about a femoral hernia?
They are at risk of incarceration which could lead to strangulation and necrosis.
45
4 What embryological defect is required for the development of a scrotal hernia?
Fully patent processus vaginalis
46
4 How is reflux into the nasal cavity normally prevented during swallowing?
Movement of soft palate to seal nasopharynx from oropharynx during pharyngeal phase and closure of upper oesphageal sphincter during oesphageal phase.
47
4 Whats Xerostomia?
Reduced flow of saliva in the oral cavity
48
4 Which nerves are needed for the swallow/gag reflex?
Glosspharyngeal CN IX afferent; Vagus CNVIII efferent
49
4 What 4 things other than the Lower Oesophageal Sphincter act to reduce Gastro-oesophageal reflux?
Mucosal rosette / folds of cardia of stomach.
Acute angle of entry od oesphagus.
Compression of (intra abdominal part of) oesphagus during increases in intra-abdo pressure.
Diaphragm, which oesophagus penetrates at T10.
50
4 Name 3 immune proteins present in saliva
IgA, lysozyme and lactoferrin
51
4 Which muscle/s is the submandibular salivary gland associated with?
Mylohyoid muscle
52
4 Autonomic fibres from which cranial nerve/s innervate/s the salivary glands?
Facial CNVII - submandibular and sublingual glands
| Glossopharyngeal CNVIX- parotid glands
53
4 What's the medical term for painful swallowing?
Odynophagia
54
5 What is the blood supply to the lesser curve of the stomach?
Anastomoses of L & R gastric arteries (which in turn originate from coeliac trunk of abdominal aorta)
55
5 Which vessels supply the gasto-omental arteries?
Left - Splenic artery
| Right - Gastroduodenal artery
56
5 Which veins do the veins draining the stomach drain into?
Portal vein, splenic vein and superior mesenteric vein
57
5 Which 3 vessels run within the free edge of the lesser omentum?
Proper hepatic artery
Hepatic portal vein
Common bile duct
58
5 What are the anatomical relations of the spleen?
Stomach,
L hemi-diaphragm,
Splenic / L colic flexure of colon and L kidney
59
5 How is the pancreas positioned in relation to the peritoneum?
The pancreas is mostly retro-peritoneal, its tail is intra-peritoneal.
60
5 At which vertebral levels would you find the duodenum?
L1-3
61
5 What are mesentery?
(Fan shaped) folds of peritoneum which attach viscera to the abdominal wall
62
5 What types of cells are found within the gastric pits?
Parietal, G, chief and mucous cells
63
5 How is the stomach adapted to facilitate mechanical disruption of gut contents?
Extra oblique layer of muscle (inside the inner circular & outer longitudinal layers of smooth muscle that most of the gut has)
64
5 What is receptive relaxation?
Vagally mediated relaxation of orad stomach in response to swallowing of food.
65
5 Give 3 functions of the low pH of the stomach
1. Denatures / unravels proteins
2. Activates proteases / digestive enzymes
3. Disinfects stomach contents / kills bacteria/pathogens
66
5 What 4 substances does stomach secrete into its lumen?
* HCL
* Intrinsic factor
* Mucus and HCO3-
* Pepsinogen
67
5 What 3 main cell types would you expect to find in the fundus of the stomach?
Mucous cells
Parietal cells
Chief cells
68
5 In which part of the stomach are most of the hormone secreting cells found?
Pylorus (G and D cells)
69
5 What 3 substances stimulate parietal cells?
Gastrin, histamine and ACh
70
5 State 2 commonly ingested substances that can damage the stomach's protective mucosa and briefly explain how
Alcohol - dissolves mucous layer
| NSAIDs - inhibit prostaglandins thus reducing blood flow
71
5 What is the most common cause of chronic gastritis in the UK?
Helicobacter pylori
72
5 What is Zollinger Ellison syndrome?
Gastrin secreting tumour of pancreas, rare but important cause of peptic ulcer diease
73
5 Which are the 1st and 2nd most common locations of peptic ulcers?
1st - proximal duodenum
| 2nd - lesser curve of stomach
74
5 What drugs would you prescribe for H pylori associated chronic gastritis?
Triple therapy of PPI + clarithromycin + amoxicillin
75
5 How can H pylori survive in the acidic stomach?
Produces urease enzyme which converts urea to ammonium increasing local pH
76
5 How does H pylori damage the epithelium? Give 3 mechanisms
Release cytotoxins that cause direct injury.
Produce urease which produces toxic ammonia.
Promotes inflammatory response.
77
5 H pylori colonisation of which part of the stomach can lead to cancer?
If colonisation is mostly int the body of the stomach
78
5 Define Peptic ulcer disease
A breach in the gastric or duodenal mucosa that extends through the muscularis mucosa
79
6 What 3 features of small intestine epithelium increase its surface area?
Microvilli
Villi
Plicae circulares
80
6 What is the function of Brunner's glands?
Produce alkaline mucin rich secretions to protect dudodenum from acidic chyme
81
6 What do paneth cells do?
Protect stem cells at the base of intestinal crypts from bacteria
82
6 How is water absorption in the large bowel controlled?
1. Tight junctions between cells reduces paracellular movement.
2. Water follows Na+ absoprtion. This is itself controlled by aldosterone inducement of Na+ transport channels.
83
6 What is the pathophysiology of Coeliac disease?
Auto-immune response triggered by gliadin fraction of gluten leading to mucosal damage which impairs digestion and causes malabsorption.
84
6 Which cells are needed for vitamin B12 absorption?
Gastric parietal cells -produce intrinsic factor that b12 binds to
Enterocytes of terminal ileum
85
6 How can PPIs cause iron deficiency?
Iron is absorbed by co-transport with H+, if gastric acid secretion is inhibited by PPIs then there may not be sufficient H+ for this.
86
6 Why would a high calcium diet be useful in hypoparathyroid disease?
High intake allows bypassing of vitamin D dependant process of Ca2+ absorption through Ca2+ATPase. Vitamin D is stimulated by PTH therefore may not be present in sufficient levels to allow adequate calcium absorption from a low intake diet.
87
6 Which transporters are needed for glucose absorption in the small bowel?
Apical SGLT1 and basolateral GLUT5
88
6 How is sucrose absorbed?
Via GLUT5 transporters in small bowel
89
6 How is most of our dietary protein absorbed in the gut?
As tri- or di-peptides via a H+ transporter / peptide transport 1 in the small bowel. These are then broken down into amino acids by cytosolic peptidases before being absorbed into the portal and then systemic circulation.
90
6 Describe the basis of Oral Rehydration Therapy
Presence of sodium and glucose in solution gives maximum influx of osmotically active substances into cell, allowing maximal water uptake.
91
6 How is release of CCK and secretin stimulated?
Presence of hypertonic chyme containing small particles and fats w/n duodenum
92
6 Why is chyme hypertonic?
Stomach wall is largely impermeable to water
93
6 What does cholecystokinin do?
Stimulates enzyme secretion from pancreas
| Stimulates bile release from gall bladder via contraction of bladder wall and relaxation of the Sphincter of Odi.
94
6 How are pancreatic acini stimulated?
By CCK and vagus nerve
95
6 Name 2 pancreatic secretions which later digest protein in the duodenum
Trysinogen
| Chymotrypsinogen
96
6/ToB Give 3 cell types found within the exocrine pancreas
Duct cells, acinar cells and centroacinar cells
97
6/Met What do the alpha and beta cells of the pancreas secrete?
Alpha - glucagon
| Beta - Insulin
98
6 Which duct receives secretions from pancreas and gall bladder?
Hepatopancreatic duct / Ampulla of Vater
99
6 How do bile salts aid digestion of fats?
Emulsify it, increasing surface area on which lipases can act
100
6 Give 3 functions of the gallbladder
```
Stores bile
Allows control of bile release into gut
Concentrates bile (removing water and ions)
```
101
6 What are the structural units of the liver?
Lobules (hexagonal arrangement of cells bile ducts and blood vessels)
102
6 Hepatocytes in which areas of the liver are most susceptible to toxic damage?
Cells in zone 1 of acini (as blood drains from periphery of lobule to centre)
103
1st yr Describe the structure of chylomicrons
Shell of phospholipids with embedded apo-proteins, enclosing triglycerides
104
6 What are the 3 main components of bile?
Bile acids
Bile pigments
Alkaline juices
105
7 Describe the blood supply to the jejunum and ileum
Vasa recta from arcades within mesentery which are supplied by Superior Mesenteric Artery. Jejunum has longer vasa recta and less arcades than ileum.
106
7 Name the lobes of the liver
Caudate (above quadrate), Quadrate (near gall bladder) Left and Right
107
7 What is the most common cause of pancreatitis?
Gall stones
108
7 Explain 2 reasons why cirrohsis can cause haematemesis
1. Hepatic fibrosis occludes and compresses sinusoids leading to portal hypertension. This causes porto-sysetmic shunting including to oseophageal junction where it produces varices. If and when these bleed, it will often cause vomiting of the blood.
2. As hepatocytes are replaced with fibrous tissue, albumin with be low. Pro-thrombin & clotting time will be low so any bleeding will last longer.
109
7 How can we assess the synthetic function of the liver?
Serum albumin concentration
Clotting factors / INR
(Also AST & ALT as these enzymes are needed for proetin synthesis)
110
7. Which 4 enzymes can be measured in the blood to assess liver damage?
```
Gamma GT (gamma glutamine transferase)
Alk Phos (ALP / alkaline phosphatase)
ALP & AST (alanine and apartate amino transferases)
```
111
7. Why is alkaline phosphatase high in biliary obstruction?
Enzyme is presnet in liver caniculi and bile ducts
112
7. What can high levels of AST (aspartate aminotransferase) indicate?
Liver, heart or muscle damage or inflammation
113
7. Give 5 non-hepatic causes of a raised alkaline phosphatase
Bone mets, osteomalaecia, hyperparathyroidism, Paget's disease and pregancy
114
7. What is the breakdown product of bilirubin normally present in urine?
Urobilin (breakdown product of conjugated bilirubin)
115
7. Why would gamma GT be high in an alcoholic patient?
Gamma GT induced by alcohol
| Also some obstruction to bilary flow from alcoholic cirrhosis
116
7. What are the 3 main types of jaundice?
Pre-hepatic / haemolytic
Hepatic
Post-hepatic / obstructive
117
8 How is the smooth muscle of the large bowel different to that of the small bowel?
Outer longitudinal layer is incomplete, consisting of the 3 bands of the teniae coli (which contract to form haustra to allow haustral shuttling)
118
8 How does aldosterone affect the colon?
Induces ENaC which facilitates the desiccation of faeces as the movement of Na+ out of the lumen creates an osmotic gradient for water to follow.
119
8 Which vitamins does the large intestine synthesise?
Vitamin K and some B vitamins including B12
120
8 What is the pathognomic histological sign of Crohn's disease?
Granuloma formation
121
8 How could you distinguish large and small bowel on histology?
Large bowel has crypts, small has villi
122
8 A 65 year old patient is seen with suspected IBD of which symptoms started 2 years ago, is it more likely to be Ulcerative colitis or Crohn's?
Crohn's (bimodal distribution whereas UC is mostly young adults)
123
8 Why is surgery not a 1st line treatment for Crohn's disease?
Crohn's can affect anywhere in GIT so won't be curative. Aim to preserve as much bowel as possible by reserving surgery for complications.
124
8 What is the most common extra-intestinal symptom associated with IBD?
MSK pain such as arthritis
125
8 Name 3 skin conditions associated with IBD
Erythema nodosum
Pyoderma gangrenosum
Psoriasis
126
8 Give 5 factors that would increase someone's risk of IBD
```
Poor diet
Smoking
Infections of GIT
Antibiotic use
1st degree relative with disease
```
127
8 What is the classical radiological sign of Ulcerative Colitis?
Lead pipe / featureless colon
128
8 What is the main microscopic change would you expect to see in a biopsy of Ulcerative Colitis?
Crypt abscesses (+ distortion, also reduced no. goblet cells)
129
8 Is perianal ulceration and/or inflammtion common in Ulcerative Colitis?
No its pretty rare
| but occurs in 75% of Crohn's patients
130
8 Where in the bowel does Ulcerative Colitis tend to affect first?
Rectum (then extends through colon)
131
8 What causes the cobblestone appearance of the gut in severe Crohn's disease?
Discrete linear ulcers that cross each other with areas of oedmatous or regenerating mucosa between them
132
8 Why is Crohn's more likely to lead to intestinal obstruction than UC?
Crohn's is transmural so narrowings due to inflammation and fibrosis are more common. Narrowing of the gut lumen is rare in UC.
133
8 What pharmacological treatments are used for IBD?
Aminosalicylates (am-ee-no-sal-i-slates), corticosteriods and immunomodulators used in stepwise approach
134
8 In what 3 circumstances might a colectomy be necessary in UC?
Inflammation not settling
Pre-cancerous changes
Toxic megacolon
135
8 What is the most common cause of retroperitoneal bleeding?
Ruptured AAA (abdo aortic aneurysm)
136
8 What is cholangitis?
a life threatening condition involving infection of the biliary tract caused by gallstones in the biliary tract or increasing from interventions and stents in the biliary tract
137
8 Give 2 causes of intraperitoneal bleeding
Ectopic pregnancy
| Duodenal ulcer
138
8 What is Charcot's triad for cholangitis?
Jaundice, fever and RUQ pain
139
8 What are the signs and symptoms of a ruptured ectopic pregnancy?
Sudden, severe abdominal or pelvic pain
Pain in lower back and/or shoulder
Dizziness or fainting
140
8 How in principle should cholangitis be managed?
Remove stone (with ERCP) *then* give antibiotics
141
8 How does acute gut ischeamia typically present?
Severe abdo pain with tenderness over affected area
Toxic - high temp, tachycardia, tachypnea, pallor etc
Hypotension
142
8 What is the commonest cause of acute gut ischeamia?
Embolism from aortic fibrillation
143
8 How is fluid lost from circulation in bowel obstruction? Give 4 ways
Sequestering of fluid in lumen
Increased secretion
Decreased reabsorption
Vomiting
144
8 Where is visceral pain of the GIT felt?
foregut: distal oestophagus and proximal duodenum- epigastric area
midgut: distal duodenum and proximal 2/3 of transverse colon - periumbilical
hind gut: distal 1/3 of transverse colon to rectum - suprapubic
145
8 Where would irritation of the parietal peritoneum be felt?
Associated dermatome (eg if diaphragmatic area would get shoulder tip pain)
146
11 List the 5 most common GI cancers in the UK in order of incidence
Bowel, Pancreas, Oesophagus, Stomach, Liver
| Bloated People Only Sing Lightly
147
11 What are the red flag symptoms for dysphagia?
```
Anaemia
Loss of weight (unintentional)
Anorexia
Recent onset of progressive symptoms
Masses/Malaena
(ALARM)
```
148
11 What type of oesophageal carcinoma is most common?
Squamous cell carcinomas
149
11 How does oesophageal carcinoma typically present?
Typically presents with progressive dysphagia
150
11 What's the prognosis in oesophageal carcinoma?
Poor ( 5% year survival at 5 years)
151
11 60 year old lady presents w/ epigastric pain. What 2 other symptoms would you most want to ask her about?
Malaena - dark, black tarry extremely offensive smelling stool
Haematemesis - vomming blood
152
11 Where in the stomach would you expect a adenocarcinoma to be?
Cardia and antrum
153
11 Give 4 risk factors for gastric cancer
Smoking
Family history
High salt diet
H pylori infection / chronic gastritis
154
11 What is the most common site for GI lymphoma?
The stomach (specifically gastric MALT)
155
11 What 4 signs/symptoms would you be particularly concerned about in a jaundiced patient?
Hepatomegaly with irregular border
Ascites
Painless
Unintentional weight loss
156
11 What are the 4 major causes of bleeding in the GIT?
Peptic and duodenal ulcers
Oesophageal varices
Acute gastritis
Gastric cancer
157
11 What is the most common cause of cancer in the liver?
Metastases eg from bowel, breast, pancreas, prostate, lung, skin
158
11 Describe the most common histology of pancreatic cancer
Most (80%) are ductal adenocarcinomas
159
11 What age range is pancreatic cancer more common in?
>60s
160
11 What's the prognosis in pancreatic cancer?
Very poor (survival stats use 18 month period)
161
11 What are the red flag symptoms in GI obstruction?
Unexplained abdominal pain
| Unintentional weight loss
162
11 Give 3 benign causes of intestinal obstruction
Diverticular disease
Volvulus
Hernias
163
11 What are the 4 things that would be most concerning when taking a history of a patient with per rectal bleeding?
Iron deficient anaemia
Unexplained weight loss
Older age
Change in bowel habit
164
11 Give 5 non-malignant causes of Per Rectum Bleeding
```
Haemorrhoids
Anal fissures
Infective gastroenteritis
Inflammatory bowel disease
Diverticular disease
```
165
11 What are the red flag potential features of a change of bowel habit history?
Iron deficient anaemia
Unexplained weight loss
Older patient (>50)
PR blood loss
166
11 Give 3 endocrinological causes of constipation
Hypothyroidism
Diabetes mellitus
Hyperparathyroidism
167
11 Describe the tissue changes involved in development of colo-rectal carcinomas
Hyperproliferation of epithelium followed by formation of adenomatous polyps which increase in size before becoming dysplastic and finally malignant
168
11 Suggest why right sided colon cancer is more likely to present late than left sided?
Mostly vague symptoms in L sided bowel as its more proximal and more distensible
169
11 What are the 4 main signs/symptoms of bowel obstruction?
Abdominal distension
Abdominal pain
Constipation
Nausea and vomiting
170
9 What are the major viral causes of diarrhoea?
Norovirus
Rotavirus
Adenoviruses
171
9 Which types of campylobacter typically cause enteritis?
C. jejuni and C. coli
172
9 What can the symptoms of campylobacter gastroenteritis mimic?
Appendicitis
173
9 Describe microscopic appearence of campylobacter
Gram negative staining
| Helical "seagull shaped"
174
9 What are the prodromal symptoms of a campylobacter infection?
Fever, rigors, aches,
| dizziness
175
9 What antibiotics would you give for a campylobacter infection? (UHL)
Fluoroquinolone or macrolide
176
9 When would you give antibiotics for a campylobacter infection?
Only if severe disease
+ risk factors (pregnant, elderly,
immunocompromised).
177
9 How long does a cyclosporal infection last?
Usually about 3 weeks
178
9 Where is Cyclospora cayetanensis endemic?
South and Central America
South and South-East Asia,
Middle East,
Africa
179
9 Why is cylospora unlikely to pass person to person?
Sporulated oocysts cause disease
| Only unsporulated oocyts shred in stool
180
9 What antimicrobial would you give for cyclospora infection?
Trimethoprim-sulphamethoxazole
181
9 What is the most common cause of epidemic
| gastroenteritis?
Norovirus
182
9 What's the incubation period for norovirus?
24-28 hours
183
9 Why is it important to wash your hands with soap and water during a norovirus outbreak?
Resists disinfection with alcohol - i.e. hand gel
184
9 What is the most common incubation period for salmonella food poisoning?
12-36 hours (can be 6-72)
185
9 How long does illness from salmonella usually last?
4-7 days
186
9 Give 4 infective causes of blood diarrhoea
Shigella
E coli O157
Salmonella enteritis
Campylobacter
187
9 When can't you give loperamide?
```
if features of:
Dysentery
E. coli 0157
Shigella
Inflammatory bowel disease
Pseudomembranous colitis
```
188
9 When should you consider antibiotics for a salmonella infection?
If patient ..
> 50 yo or < 6 months
cardiac valve disease
immuno-compromised
189
9 What type of bacteria is shigella?
Non-motile unencapsulated gram negative bacilli
190
9 What are the classic symptoms of bacillary dysentry?
Diarrhoea with blood and mucus / "currant jelly" stools
| Painful abdo cramps
191
9 Describe toxicity of shigella dysenteriae
Produces exotoxin called Shiga toxin which is enterotoxic and cytotoxic.
192
9 Which strain of shigella causes the most serious infections?
Shigella dysenteriae
193
9 Give 2 likely causes of persistent (>2wks) traveller's diarrhoea
Giardia lamblia
| Cyclospora spp
194
9 Give 3 ways you can examine a patient's hydration status
Take blood pressure and pulse including looking at postural variation
Inspect mucous membranes
Evaluate skin turgor
195
9 What system could you use when looking at an abdominal X ray?
ABC
| air/gas, bowel, calcifications
196
9 What does the small bowel look like on Xray?
Usually central
Lines across whole lumen from plicae circulares
Width shouldn't be > height of vertebral body
197
9 What are the symptoms of small bowel obstruction?
Early vomiting
Mild distention
Late constipation
Pain every 2-3 minutes
198
9 How frequent would you expect colicky pain of large bowel obstruction be?
Every 10-15 minutes
