Infections of the GI tract Flashcards

1
Q

What is the difference between microbiome and microbiotia?

A

Microbiome: all the genome within the gut environment

Microbiota: all the organisms within the gut environment

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the functions of the gut microbiota?

A
  • pathogen inhibition
  • immune protection
  • nutrient metabolism - synthesis vit B + K
  • Drug metabolsim
  • Gut brain axis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What approach would you take on investigating the symtpoms of a patient with a suspected GI infection?

A
  • Is there diarrhoea? - onset, duration, frequency, consistency
  • Is there mucus/ blood in stools?
  • Is there vomiting? - onset, frequency
  • Is there pain? - site, radiation, intermittent, continuous
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What Past medical history would be useful to know in a suspected GI infection?

A
  • History of immunocompromise / immuodeficiency
  • Any other GI conditions
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are some important social questions to ask if someone presents with a suscpected GI infection?

A
  • Recent travel history? - where, when and how long, what they did whilst they were there
  • Drug history - recent antibiotics? proton pump inhibitors? laxatives? immunsuppressants?
  • Social History - occupation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What things can you look for on GI examination that can help establish if there is a GI infetion?

A

Volume status: Check mucous membranes, BP, pulse, JVP

Abdominal exam: ileus, peritontitis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What investigations can be done on a stool sample to help identify GI infection?

A
  • Stool culture
  • Enzyme immunoassay
  • PCR
  • Microscopy

Impossible to do all, need to know what sample you’re looking for

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What infectious causes can cause watery diarrhoea?

A
  • Norovirus
  • Rotavirus
  • C. difficile
  • Enterotoxigenic E. Coli
  • Giardia lamblia
  • Cryptosporidium parvum
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What infectious causes can cause inflammatory diarrhoea?

A
  • Non- typhoidal salmonella
  • Campylobater
  • Clostridiodes difficile
  • Shigella
  • E. coli O157
  • Entamoeba hysoltica
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

What are the 2 general subdivisions of salmonella infection?

A

Typhoidal salmonella which causes enteric fever (Salmonella typhi and Salmonella paratyphi)

Non-typhoidal salmonella whichc causes gastroenteriris (Salmonells enteritidis, Salmonella virchow)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What are some of the general features of non- typhoidal salmonella?

A
  • Diarrhoea
  • Nausea
  • Vomiting
  • Abdominal Cramps
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

How is non- typhoidal salmonella transmitted?

A
  • In food
  • Faeco- orally
  • Animals
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are some of the complication sof non-typhoidal salmonella infection?

A
  • Bacteraemia
  • Endovascular infections
  • Abscesses
  • Osteomyeltitis
  • Septic arthritis
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

How do you treat non-typhoidal salmonella?

A

usuall self limiting

If bateraemic: can use antibitoics, ciprofloxacin, azithromycin, ceftriaxone

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What are the most 2 common organisms of infection with camylobacter?

A

Camplyobacter jejuni

Camplyobacter coli

Gram -ve corkscrew like bacterium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are some of the general features of a campylobacter infection?

A
  • abdominal cramping
  • diarrhoea
  • may have fever and malaise
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is the transmission route of camplyobacter?

A

Food, water or animal contact

18
Q

How do you treat campylobacter?

A

Usually self limiting

Treat immunocompromised patients, elderly or severe infetion with macrolides or fluoroquinolones

19
Q

What are some of the complications of a campylobacter infection?

A
  • Reactive Arthritis
  • Guillain-Barre Syndrome (GBS) - ascending paralysis
20
Q

What kind of food/ drink can cause campylobacter?

A
  • Uncooked poultry - peaks on BBQ over summer
  • Milk- transmitted by birds pecking milk tops
  • Uncooked defrosted turkey
21
Q

Which types of shigella can cause dysentry? (blood diarrhoea)

A

Shigella dysenteria 1 / Shigella flexneri

22
Q

What are some of the general features of an infection with Shigella?

A
  • Fevers
  • Frequent low volume, blood stools
  • Tenesmus
  • Nausea and vomiting usually asbent
23
Q

How can shigella be trasmitted?

A
  • Faeco - oral
  • Food and water
  • Person-to-person can occur due to low infective dose
24
Q

What are some of the complications of shigella infections?

A

Intestinal (rare): proctisis, rectal prolapse, toxic megacolon, perforation, obstruction

Systemic: bacteraemia, seizures (children), reactive arthritis, haemolytic iraemic syndrome

25
Q

What treatment can you give for shigella?

A

Usually self limiting

If not give ciprofloxacin, azithromycin, ceftriaxone

26
Q

Which E.coli subtype prodcues shiga toxin?

A

E. coli O157

27
Q

Describe the clinical features and aetiology of E.coli O157 infection

A
  • Very contagious infection
  • causes painful, bloody diarrhoea and haemolytic uraemic syndrome
  • Children <10 year and elderly particularly vulnerable
  • No fever
  • Worsened by antibiotics → cause more toxin to be produced
28
Q

What is haemolytic uraemic syndrome?

A

Diease characterised by: Non immune mediated haemolytic anaemia, thrombocytopenia and acute kidney injury

29
Q

What kind of bacteria is clostridiodes difficile?

A

Anaerobic gram negative bacilli

30
Q

How do c. dificile bacterium remain in the environment for so long?

A

Produce spores that are very resistant

Not killed by handgel - always use soap and water after a diaorrhoea infection

31
Q

What are some risk factors for developing an infection from clostridiodes difficile?

A
  • Age >65
  • Antibiotic therapy
  • PPI therapy
  • prolonged hospitalisation
32
Q

What complications can arise from infection with clostridiodes difficile?

A
  • Toxic megacolon,
  • colitis
  • perforation
33
Q

How do you treat a clostriodes difficile infection?

A
  • Metrondiazole
  • Oral Vancomycin
  • Fidazomicin - superior for recurrent infection
  • Faecal microbiota transplant - repooulates gut with healthy microbiota
34
Q

Describe the clinical features and aetiology of a norovirus infection

A
  • Causes profuse diarrhoea and vomiting
  • Transmitted faceo-orally, direct contact or aerosols
  • Highly infectious due to low infective dose
  • Usually self limiting (1-2 days)
35
Q

Describe the clinical features and aetiology of a rotavirus infection

A
  • Cause of gastroenteriris in young children
  • Transmitted faeco-rally
  • highly infective
  • General features of diarrhoea, vomiting and fever
  • Usualy self limiting with supportive treatment
36
Q

What rare complications can arise from a rotavirus infection?

A
  • seizures
  • encephalopathy
  • acute encephalitis
37
Q

Describe the clinical features and aetiology of a cryptosporidium infection

A
  • Intracellular protozoan parasite
  • Cryptosporidium parvum main species to cause infection
  • Associated with sporadic, water associated outbreaks i.e. swimming pools
  • Usually self limiting within 10-14 days
  • Treat with nitazoxanide if immunocompromised
38
Q

Describe the clinical features and aetiology of a giardia infection

A
  • Caused by giardia duodenalis, a protozoa parasite
  • can last in cold water for months
  • Children, immunocompromised patients and cystic fibrosis are high risk
  • Transmited in food, water, faeco-orally
  • Features of malaise, steatorrhoea, abdominal cramps and bloating
  • Chronic infection can cause malabsorption and weight loss
39
Q

How do you treat a giardia infection?

A

NOT self limiting

If symptomatic give metronidazole or nitazoxanide

40
Q

Describe the clinical features and aetiology of a entamoeba histolytica infection

A
  • protozoan parasite
  • most infections asymptomatic
  • Can cause amoebic dysentry
  • Transmitted in food, water, faeco-orally highly transmissable
  • General features: diarrhoea, abdominal pain, fulminany colitis with necrosis and perforation
  • Treat with high dose metronidazole followed by an intraluminal agent