Week 5

Question 1

What should you use to treat gram negative coliforms?

Answer 1

Gentamycin

Be gentle with your cauliflowers

Question 2

What would you use to treat anaerobes

Answer 2

Metronidazole

No oxygen in the metro

Question 3

Define colonisation

Answer 3

Establishments of microorgansims within a host

Question 4

Define virulence

Answer 4

Likelihood of pathogen to cause disease

Question 5

What is the most common organism causing gastritis?

Answer 5

H. Pylori

Gram negative

Question 6

When attempting to grow a gram negative rod what agar should you use?

Answer 6

MacConkey agar as lactose fermenters turn it pink

Question 7

If you suspect sepsis, you should investigate using the sepsis 6 bundle. What does this include?

Answer 7

BUFALO or give 3 take 3

Blood cultures
Urine output
Fluid resusitation
Antibiotics IV
Lactate measure (sign of tissue death)
Oxygen

Question 8

If you cannot use gentamicin to treat a gram negaive coliform what should you use?

Answer 8

Aztreonam

Question 9

Young male in 20s presents with collicky abdominal pain, diarrhoea, bleeding in stool, and weight loss. He also smokes. Potential diagnosis?

Answer 9

Ulcerative colitis

Crohns (more likely due to his age) would need endoscopy to identify

Question 10

Histologically a young 20 year old male presents with cobblestoning mucosa, with misshapen crypts and inflammation of the cryps. The inflammation is full thickness through all layers of the intestine. Diagnosis

Answer 10

Crohns disease

Question 11

What is the treatment for crohns?

Answer 11

Monoclonal antibodies
Steroids
Surgery (but not curative as cannot take out entire small intestine due to absorptive function)

Question 12

Male of age 33 presents with diarrhoea with puss and mucous and occasional blood and abdominal pain. He wakes in the right to poo, and has tenesmus. He doesnt smoke. Histologically it is inflammation of the mucosa and submucosa of the large bowel

Answer 12

Ulcerative coliits

Question 13

Give an example of a symptom that would indicate crohns disease in the mouth

Answer 13

Angular chielitis

Question 14

What is the purpose of faecal calprotectin testing?

Answer 14

To differentiate between IBD and IBS.

If positive then IBD

Question 15

What are some of the drugs to treat ulcerative coliits?

Answer 15

Aminosalicylates e.g balsalazide, sulfasalazine, olsalazine

Corticosteroid e.g prednisolone

Infliximab, adalimumab

Question 16

What are the treatment options for crohns disease

Answer 16

Steroids; prednisolone

Aminosalicylates; balsalzide, sulfalazine

Immunosuppresants; Azathioprine, mercaptopurine

ANti-TNF alpha; infliximab, adalimumab, inflectra and remsima

Question 17

What is the most common organism to cause vomiting on cruise ships? Treatment?

Answer 17

Norovirus

Supportive; IV fluids

Question 18

Man presents with fever, headache, constipation, dry cough and recent travel to India. Causative organism?

Answer 18

Salmonella Typhi causing enteric fever

Question 19

What organism can cause HUS?

Answer 19

E. Coli 0157

Question 20

What organisms usually cause hepatic jaundice?

Answer 20

Hepatitis A, E
Malaria
Salmonella typho (enteric fever)

Question 21

Women presents with stomach pain, with diarrhoea, bloating and weight loss. She went on holiday to subsaharan Africa 3 months ago. Potential organism?

Answer 21

Giardia

Question 22

How can water be transported across enterocytes?

Answer 22

Through aquaporins or transcellularly

Question 23

How can sodium be transported across the enterocytes?

Answer 23

Through sodium potassium pump (secondary active transport)

NHE2 (sodium hydrogen exchanger)

ENaC (epithelium sodium channels. aldosterone regulated)

Question 24

How can chlorine be absorbed through enterocytes?

Answer 24

Passively by transcellular or paracellular routes, in attempt to compensate for the influx of sodium + ions

Question 25

What can stimulate the excretion of chloride ions into the lumen from the CFTR transporter?

Answer 25

``` CAMP increased Ca2+ ions in the lumen cGMP increased E.coli and cholera enterotoxins (hence why causes diarrhoea. Does this by activating adenyl cyclase that increases cAMP) Misoprostol Acetylcholine and serotonin (5-HT) Histamine Laxatives ```

Question 26

What are some of the conseqeuences of diarrhoea?

Answer 26

Dehydration Metabolic acidosis (due to HCO3- loss) Hypokalaemia (K+ loss)

Question 27

What are some antidiarrhoeal agents?

Answer 27

Loperamide Diphenoxylate Codiene (also opiate)

Question 28

What are some of the treatments for constipation?

Answer 28

Methycellulose; bulk laxative Magnesium sulphate; osmotically active Doxucasodium; faecal softners Sodium picosulphate; stimulant

Question 29

Man of 65 years presents with a 3 month change of bowel habit, he is bleeding in stool, colicky pain, weight loss and unexplained iron deficiency anaemia. He also has ulcerative colitis, likely diagnosis? Investigations?

Answer 29

Colorectal cancer CT colonography (If younger could do barium enema, colonoscopy)