GI Infections

Question 1

Suprantigen in GI tract
Vomiting, watery non-bloody diarrhoea
B haemolytic colonies on blood agar
From poor food handling
Appears in tetrad clusters G stain

Answer 1

Staph Aureus

Question 2

Reheated fried rice

Answer 2

Bacillus Cereus

Question 3

Bacillus Cereus toxins (x2)

Answer 3

Heat stabile (emetic) and Heat labile (diarrhoeal)

Question 4

Treatment Bacillus Cereus?

Answer 4

None, self limiting

Question 5

Treatment S Aureus?

Answer 5

None, self limiting

Question 6

Canned foods, bacteria in honey (infants)

Preformed toxin

Answer 6

Clostridium Botulinum

Question 7

Preformed toxin, block of ACh release

Descending paralysis

Answer 7

Clostridium Botulinum

Question 8

Treatment of Clostridium Botulinum

Answer 8

Antitoxin

Question 9

Reheated meat, superantigen causes systemic toxicity
Vomiting, watery diarrhoea, lasts 24 hours
rapid onset

Answer 9

Clostridium Difficile

Question 10

Aesculin positive with tumbling motility

Answer 10

Listeria Monocytogenes

Question 11

Unpasteurized dairy, ‘cold enhancement’

Answer 11

Listeria Monocytogenes

Question 12

Treatment of Listeria Monocytogenes

Answer 12

Ampicillin (+ ceftriaxone, cotrimoxazole)

Question 13

E. Coli - ETEC

Answer 13

Enterotoxigenic E. coli

Traveller’s diarrhoea

Question 14

E. Coli - EPEC

Answer 14

Enteropathogenic E. coli 
Infantile diarhoea (Paeds)

Question 15

E. Coli - HUS (3 features)

Answer 15

Anaemia, thrombocytopaenia, renal failure

Question 16

E. Coli - EIEC

Answer 16

Invasive dystentry

Enteroinvasive E. Coli

Question 17

E. Coli - EHEC

Answer 17

Haemorrhagic (verotoxin)

Enterohemorrhagic E Coli

Question 18

Multiplies in Peyer’s patches

Answer 18

Salmonella typhi

Question 19

Rose spots, slow onset fever, bradycardia

CONSTIPATION

Answer 19

Salmonella typhi

Question 20

Treatment of E. Coli

Answer 20

Self limiting but can treat with Ciprofloxaxin

Question 21

Treatment of Salmonella

Answer 21

Ceftrioxone, or ciprofloxacin

Question 22

Poultry, meat, eggs

non-lactose fermenting

Answer 22

Salmonella enteritidis

Question 23

Handling reptiles

Answer 23

Salmonella

Question 24

Fever, pain, bloody diarrhoea
Very low effective dose
Production of enterotoxin

Answer 24

Shigellae

Question 25

Rice water stool

Answer 25

Vibrio Cholerae

Question 26

Increased CAMP, efflux of Cl- into lumen | Massive diarrhoea without inflammatory cells

Answer 26

Vibrio Cholerae

Question 27

Raw seafood, common in Japan | Diarrhoea x3 days

Answer 27

Vibrio Parahaemolyticus

Question 28

Shellfish handler/diver

Answer 28

Vibrio Vulnifcus

Question 29

Treatment of Vibrio Parahaemolyticus/Vulnifcus

Answer 29

Doxycycline

Question 30

Bloody foul smelling stool Prodrome - fever, abdo pain Oxidase +ve Poutry, meat, unpasteruised milk

Answer 30

Campylobacter Jejuni

Question 31

Treatment of Campylobacter Jejuni

Answer 31

Erythromycin or ciprofloxacin

Question 32

Mesenteric adenitis with necrotising granulomas Farm animals Extra GI symptoms - arthritis, erythema nordosum

Answer 32

Yersinia enterocolitica

Question 33

Flask shaped ulcer

Answer 33

Entamoeba Histolytica

Question 34

Motile trophozoite/non motile cyst | 4 nuclei

Answer 34

Entamoeba Histolytica

Question 35

Treatment Entamoeba Histolytica (x2)

Answer 35

Metronidazole + Paramomycin

Question 36

Pear shaped trophozoite

Answer 36

Giardia lamblia

Question 37

Travelers, hikers, cruise ships, MSM | Malabsorption of protein and fat - foul smelling non-bloody diarrhoea

Answer 37

Giardia lamblia

Question 38

String test | 2 nuclei

Answer 38

Giardia lamblia

Question 39

Treatment of Giardia lamblia

Answer 39

Metronidazole

Question 40

Swimming pools, particularly immunocompromised | Oocysts in stool by Kinyoun Acid Fast Stain

Answer 40

Cryptosporidium parvum

Question 41

Treatment cryptosporidium parvum

Answer 41

Paromomycin

Question 42

dsDNA, 'wheel like' | Watery diarrhoea

Answer 42

Rotavirus