Microbiology

Question 1

Which of the following enteric pathogens genus is most likely to become systemic ?

1. Shigella flexneri
2. Salmonella enterica
3. Escherichia coli
4. Yersinia enterocolitica
5. Vibrio cholerae

Answer 1

2. Salmonella enterica

Question 2

What are the primary barriers of the Gut?

Answer 2

Faeces

Question 3

What are the secondary control barriers?

Answer 3

Fluids
Fingers
Flies
Fields
Food

Question 4

Main worldwide gastrointestinal infection virus?

Answer 4

Rotavirus

37% diarrhoea hospitalizations/year due to rotavirus
• typically babies & young children

Question 5

Treatment for Rotavirus

Answer 5

Rotarix

• oral routine vaccine
• 8-12 wk old babies
• 70% prevention

Question 6

Treatment for norovirus?

Answer 6

Nothing

Question 7

Coming GI infections in Uk ranked

Answer 7

Campylobacter
Norovirus
Cryptosporidium 
Salmonella
Giardia
Rotavirus
E. coli 0157
Shigella sonnei

Question 8

Symptoms of gastritis?

Answer 8

Nausea
Vomiting
Abdominal discomfort

Question 9

Symptoms of gastroenteritis

Answer 9

Diarrhoea 
Nausea 
Vomiting 
Abdominal discomfort 
Pain
Low fever 
Mucosa inflammation (low)
Abdominal cramps (low)

Question 10

Symptoms of enterocolitis

Answer 10

Diarrhoea 
Blood (low)
Nausea (low)
Vomiting (low)
Pain
Abdominal discomfort (low)
Mucosal inflammation 
Fever (low)

Question 11

Symptoms of dysentery?

Answer 11

Diarrhoea 
Blood
Mucus/pus
Nausea (low)
Vomiting (low)
Pain
Abdominal cramps 
Mucosa inflammation 
Fever

Question 12

If there is NO FEVER or CELLULAR MATERIALS in laboratory samples – it is more likely to be?

Answer 12

a toxin- based infection

Question 13

Symptoms with viruses?

Answer 13

• nausea & vomiting are common
• and obviously diarrhoea
• fever may occur (not necessarily)
• bloody stool & inflammation typically absent

Question 14

Characteristics of Colitis

Answer 14

patient has diarrhoea

• passage of 3 or more unformed stools / day

and the patient has evidence of colonic inflammation:

• positive fecal markers (e.g., leukocytes, lactoferrin)
• passage of small volume stools with blood or mucus (dysentery)
• colonic mucosal inflammation on endoscopy (colonoscopy/sigmoidoscopy)

Question 15

If colitis is linked to an infectious agent or toxins that have been identified microbiologically epidemiological key it’s called

Answer 15

Infectious colitis

Question 16

What is the infectious disease process?

Answer 16

Exposure to pathogens

Adherence to skin or mucosa

Invasion through epithelium

Colonisation and growth: production of virulence factors

Toxicity(toxin effects are local systemic) Or invasive ness (further growth at original and distant sites)

Tissue damage & disease

Question 17

What are local infections?

Answer 17

1- Remotely-produced toxin: local/distant damage

         Vibrio cholerae (cholera toxin) Staphylococcus aureus (enterotoxins)
         Escherichia coli (ETEC)

2- superficial colonization

  Shigella
  Entoamoeba histolytica
  EPEC

Question 18

What are professionals infections?

Answer 18

Deep invasion

 Salmonella typhi 3 (enteric/typhoid fevers)
  HAV 
 Campylobacter

Question 19

What are opportunistics infections?

Answer 19

Epithelium perforation Causing systemic infections

      Bacteroides fragilis
      Staphylococcus aureus 
       CoNS 
       Candida
     E. Coli

Question 20

Main cause of watery diarrhoea?

Answer 20

Salmonella

Campylobacter

Question 21

Main. Sure of bloody diarrhoea?

Answer 21

EHEC

Shugella

Question 22

Serotype 9157 of E.Coli leads to?

Answer 22

Dysentery via shiva or shiva-like toxins

Question 23

Shiga toxins vs shiga-like toxins

Answer 23

Shiga toxin in Shighella dysenteriae

Shiga-like toxins = verotoxin in EHEC, VTEC , STEC