CP11-7 GI Infections

Question 1

What sites in the GI tract are sterile?

Answer 1

Peritoneal space
Pancreas
Gall balder
Liver

Question 2

What are some non-sterile sites of the GI tract?

Answer 2

Mouth
Oesophagus
Stomach
Small bowel
Large bowel

Question 3

Does presence of all bacteria e.g. neisseria meningitides and strep pneumoniae, in the pharynx always mean there is infection?

Answer 3

No - a small amount of these bacteria can be present in normal pharyngeal flora

Question 4

What are some GI infection signs seen on the mouth?

Answer 4

Angular cheilitis
Oral herpes simplex
Hairy leucoplakia

Question 5

What are 3 examples of dental infections?

Answer 5

Caries
Pulpitis
Periapical abscesses

Question 6

What are some examples of periodontal infection?

Answer 6

Gingivitis
Periodontitis
Periodental abscesses
Vincent’s angina aka acute necrotising ulcerative gingivitis
Oral facial space infections if spread.

Question 7

What are the most common deep neck space infections?

Answer 7

Peritonsillar abscess aka a quinsy
Acute suppurative parotitis

Question 8

What are some uncommon deep neck space infections?

Answer 8

Ludwig’s angina (submandibular space infections)
Parapharyngeal space infections - often have carotid sheath involvement

Question 9

What is mucositis?

Answer 9

Inflammation of the mucous membranes if the GI tract

Question 10

Who is most likely to get mucositis?

Answer 10

Chemotherapy patients - especially if have pre-existing periodontal disease.

Question 11

What is another name for an effort rupture of the oesophagus?

Answer 11

Boerhaave syndrome

Question 12

What happens as a consequence of intrathoracic oesophageal rupture?

Answer 12

Chemical mediastinitis, with mediastinal emphysema and inflammation which can lead to bacterial infection and mediastinal necrosis.

Question 13

How does H. Pylori spread?

Answer 13

Faecal oral/ oral oral exposure

Question 14

What percentage of h.pylori infections lead to ulcer disease?

Answer 14

10-15%

Question 15

What are consequences of h.pylori infection?

Answer 15

Pain
Bleeding
Perforation of stomach

Question 16

What allows h.pylori to penetrate the gastric mucus layer?

Answer 16

Formation of ammonia that neutralises gastric acid by bacterial ureases hydrolysing gastric luminal urea. Ammonia acts as a protective layer

Question 17

What is the most common biliary tract infection?

Answer 17

Cholangitis

Question 18

How do patients with cholangitis usually present?

Answer 18

Fever
Abdominal pain
Jaundice

Known as charcot’s triad

Question 19

What bacteria most commonly cause infective cholangitis?

Answer 19

Enterobacteriaceae and enterococcus species

Question 20

How do patients with cholecystitis present?

Answer 20

Abdominal pain
Fever
History of fatty food ingestion one hour prior to onset of pain
With gall stones usually

Question 21

What LFTs are important to look at in cholangitis?

Answer 21

Conjugated bilirubin
Serum ALP
GGT

Question 22

What commonly causes bacterial overgrowth in the small bowel?

Answer 22

Achlorhydria
Impaired bowel motility
Blind loops of bowel
Surgery
Radiation damage

Question 23

How does bacterial overgrowth In the small bowel affect the body?

Answer 23

Bacteria may bind to vitamins e.g. vit B12, use nutrients and produce metabolites like fatty acids

Question 24

What is associated with bacterial overgrowth of small bowel?

Answer 24

Malabsorption
Chronic diarrhoea

Question 25

What is Whipple’s disease?

Answer 25

Infection of tropheryma whipplei affecting people with a rare immune defect causing joint symptoms, chronic diarrhoea, malabsorption and weight loss which develop over time. Usually only considered after other diagnoses are excluded.

Question 26

What is the aetiology of liver abscesses?

Answer 26

Ascending biliary tract infection Can occur in portal vein after peritonitis or colonic perforation Haematogenous causes e.g. endocarditis

Question 27

What is a GI disease we can get from un-wormed dogs?

Answer 27

Hydatid cyst

Question 28

How does mycobacterium tuberculosis affect the GI tract?

Answer 28

Causes local symptoms like non healing oral ulcers, gastric ulcers and enterocutaneous fistulas

Question 29

What site of the GI tract is most commonly affected by tuberculosis?

Answer 29

Ileo-caecal area

Question 30

What are some infection complications of pancreatitis caused by enteric bacteria?

Answer 30

Necrotising pancreatitis Peripancreatic fluid collection Pancreatic pseudocyst Acute necrotic collection Walled off necrosis

Question 31

How is a complicated intra-abdominal infection defined?

Answer 31

An infection that extends beyond the hollow viscus of origin into the peritoneal space and is associated with either abscess formation or peritonitis

Question 32

What is the most common cause of complicated intra-abdominal infections

Answer 32

Perforation of an inflamed organ e.g. gallbladder, appendix, duodenum

Question 33

How is complicated diverticulitis treated?

Answer 33

With antibiotics and surgery e.g. abscess drainage or resection of affected bowel

Question 34

How does treatment of appendix differ if it is complicated vs uncomplicated?

Answer 34

Both treated with surgical management plus antibiotics in complicated but only a single dose of antibiotic prophylaxis in uncomplicated

Question 35

What are some predisposing factors for intra abdominal abscesses?

Answer 35

Peptic ulcer perforation Perforated appendix Perforated diverticulum Mesenteric ischemia/bowel infarction Pancreatitis/pancreatic necrosis Penetrating trauma Postoperative anastamotic leak

Question 36

How do patients with an intra-abdominal abscess present?

Question 37

What is spontaneous bacterial peritonitis?

Answer 37

An ascitic fluid infection without an evident intra-abdominal surgically treatable source which occurs due to bacteria within the gut lumen crossing the intestinal wall into mesenteric lymph nodes which rupture due to portal hypertension.

Question 38

Who is most likely to have spontaneous bacteria peritonitis?

Answer 38

Patients with advanced cirrhosis and ascites

Question 39

How is spontaneous bacterial peritonitis diagnosed?

Answer 39

With ascitic fluid bacterial culture showing elevated ascitic fluid absolute polymorphonuclear leukocyte (PMN) count of >250 cells/mm3

Question 40

What infection is common in patients with bowel cancer?

Answer 40

Bacteraemia caused by strep bovis aka s.gallolyticus which is associated with endocarditis