Intra-abdominal infection and gastroenteritis

Question 1

Blood tests for intra-abdo infection

Answer 1

FBC- neutrophilia/neutropenia
CRP raised
LFTs abnormal in hepatobiliary disease

Question 2

Imaging in intra-abdo infection

Answer 2

CXR- consolidation, effusion, low lobe pneumonia can present as abdo pain
USS- masses, free fluid, dilated bile ducts
CT

Question 3

Rx of abscess

Answer 3

Drainage

Question 4

Antibiotics for source other than intestinal?

Answer 4

Depends on source

Question 5

Flora of GI tract that might cause intra-abdo infection

Answer 5

E. coli 
Pseudomonas
Bacteroides
Prevotella
Enterococcus
Clostridium

Question 6

Are there more obligate anaerobic bacteria or facultative anaerobes in the colon?

Answer 6

Obligate

Question 7

List the pathongens that cause gastroenteritis

Answer 7

Bacillus cereus
Vibrio cholerae
Salmonella
Campylobacter
Shigella
E coli
Staph aureus
Enteamoeba hist.
Giardia lamblia
Cryptosporidium
Norovirus
Rotavirus
(and can also get non-infective)

Question 8

Complications of gastroenteritis

Answer 8

Dehydration
Renal failure
Haemolytic uraemic syndrome
Toxic megacolon
Guillain-Barre Syndrome
Salmonella

Question 9

What tests would you do on a stool sample for gastroenteritis

Answer 9

OCP- ova, cysts, parasites
MC&S- microscopy, culture and sensitivity
C. diff toxin

Question 10

How is cryptosporidium gastroenteritis spread?

Answer 10

waterborne (oocytes resistant to chlorine based disinfectants)

Question 11

Which bacterial causes of gastroenteritis produce enterotoxins?

Answer 11

Bacillus cereus
Vibrio cholerae
C diff
C perfrigens
Staph aureus
Ecoli

Question 12

Which bacterial causes of gastroenteritis have a mechanism of adherence to cells?

Answer 12

Shigella
E. coli
Campylobacter jejuni
Salmonella

Question 13

What is the affect of the E. Coli strain EHEC/VTEC

Answer 13

Enterohaemorrhagic

Colitis/HUS

Question 14

What is the affect of the E. Coli strain ETEC

Answer 14

Enterotoxigenic

Traveller’s diarrhoea

Question 15

What is the affect of the E. Coli strain EAggEC

Answer 15

Enteroaggregative

Traveller’s diarrhoea

Question 16

What is the affect of the E. Coli strain EIEC

Answer 16

Enteroinvasive dysentry like

Question 17

What is the affect of the E. Coli strain EPEC

Answer 17

Enteropathogenic

Childhood diarrhoea

Question 18

E. Coli strain 0157 uses what virulence factor?

Answer 18

Shiga toxin virulence factor

Question 19

Source of E coli 0157?

Answer 19

Cattle

Question 20

Severe complication of 0157?

Answer 20

Haemolytic uraemic syndrome in 10-15% because acts on RBCs

Question 21

Mechanism of 0157 toxin

Answer 21

Similar to cholera- g proteins activated, more cAMP, more ion channels activated, increased Cl efflux, water follows into the gut.

Question 22

Why can killing the bacteria make e coli worse?

Answer 22

More toxins released

Question 23

Does salmonella produce a toxin?

Answer 23

No

Question 24

4 strains of salmonella

Answer 24

S. typhi
S. paratyphi
S. enteritidis
S. typhimurium

Question 25

Typhoidal strains of salmonella……?

Answer 25

affect cells outside of the GI tract also

Question 26

Treatment of gastroenteritis?

Answer 26

Supportive
Avoid Abx except:
-Very young/old
-Campylobacter
-Spread outside GI tract (+ve blood culture)

Question 27

C. diff treatment

Answer 27

Metronidazole/vancomycin (oral)

Faecal transplant

Question 28

Treatment for intraperitoneal infection of intestinal source

Answer 28

65yrs- piperacillin/tazobactam