Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Year 3 - infection > Infectious Diarrhoea - part 1 > Flashcards

Infectious Diarrhoea - part 1 Flashcards

1
Q

what is Diarrhoea?

A

• subjective definition

fluidity and frequency - a change in fluidity and frequency in comparison to normal

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

what is Gastro-enteritis?

A

• objective

  • three or more loose stools/day
  • accompanying features
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

what is Dysentery?

A

• obvious

  • large bowel inflammation, bloody stools

intestinal inflammation, primarily of the colon. It can lead to mild or severe stomach cramps and severe diarrhea with mucus or blood in the feces

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

picture of the bristol stool chart

Guide on wards to see if things are getting better or worse

Gastroenteritis tend to have a score of 6 or 7

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

what is the epidemiology of gastro-enteritis?

A
  • Contamination of foodstuffs - Intensively farmed chicken and campylobacter
  • Poor storage of produce - Bacterial proliferation at room temperature
  • Travel-related infections e.g. Salmonella
  • Person-to-person spread - norovirus
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

how common are infectious intestinal diseases and how many of them need medical treatment?

A
  • 25% of population have Infectious intestinal disorder each year
  • 2% of population visit GP because of GI infection each year
  • For each reported case there are 10 GP consults and 147 community cases that are unreported
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

what are the commonest causes of infectious intestinal diseases?

A

• Viruses are commonest cause with campylobacter being the commonest bacterial pathogen

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

only a _____ proportion with infectious intestinal diseases come into hospital

A

small

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

what are the trends seen in food poisoning?

A
  • There are more than 500,000 cases of food poisoning a year from known pathogens
  • Campylobacter is the most common foodborne pathogen, with about 280,000 cases every year
  • Salmonella is the pathogen that causes the most hospital admissions – about 2,500 each year
  • Poultry meat was the food linked to the most cases of food poisoning, with an estimated 244,000 cases every year
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Global mortality

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

what are the numbers of the different causes of gastro-enteritis in scotland?

A
  • Campylobacter 6,096 - 112.8 per 100,000 population
  • Salmonella 751 - 13.9 per 100,000 population
  • E. coli O157 151
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the defences against enteric infections?

A
  • HYGIENE
  • stomach acidity - antacids (If taking antacids then much less protection and more risk) and infection
  • normal gut flora (Gut flora protect against infections) - Cl. difficile diarrhoea
  • immunity - HIV + salmonella
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

what is the mos timportant defence against enteric infections?

A

hygiene

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

what are the different kinds and clinical features of diarrhoeal illness?

A
  • Non-inflammatory/secretory e.g. cholera
  • Inflammatory e.g. shigella dysentery
  • Mixed picture e.g. C. difficile
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

what causes non-inflammatory diarrhoeal illness?

A

secretory toxin-mediated

  • cholera - increases cAMP levels and Cl secretion
  • enterotoxigenic E. coli (travellers’ diarrhoea)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

what are the clinical features of non-inflammatory diarrhoeal illness?

A

frequent watery stools with little abdo pain

No inflammation, just frequent watery stools

17
Q

what is the treatment of non-inflammatory diarrhoeal illness?

A

rehydration mainstay of therapy

18
Q

What is the mechanism of diarrhoea in cholera (non-inflammatory)?

A

Increased cAMP results in loss of Cl from cells along with Na and K

Osmotic effect leads to massive loss of water from the gut

19
Q

what causes inflammatory diarrhoeal illness?

A

bacterial infection/amoebic dysentery

20
Q

what are the clinical features of inflammatory diarrhoeal illness?

A

inflammatory toxin damage and mucosal destruction

pain and fever

21
Q

what is the treatment of inflammatory diarrhoeal illness?

A

antimicrobials may be appropriate but rehydration alone is often sufficient

22
Q

how do you assess a patient?

A
  • Symptoms and their duration - >2/52 unlikely to be infective gastro-enteritis (may be IBD)
  • Risk of food poisoning - Dietary (often unreliable), contact, travel history
  • assess hydration - postural BP, skin turgor, pulse
  • features of inflammation (SIRS) - fever, raised WCC
23
Q

Fluid and electrolyte losses - how much is lost?

A

• Can be severe with secretory diarrhoea - 1-7 l fluid per day containing 80-100 mmol Na

24
Q

what may occur due to sodium and potassium loss?

A

Hyponatraemia due to sodium loss with fluid replacement by hypotonic solutions

Hypokalaemia due to K loss in stool (40-80mmol/l of K in stools)

25
Q

what are some investigations you may do to assess the pateint?

A
  • stool culture (main stay of investigation) +/- molecular or Ag testing (Molecular techniques to detect toxins)
  • blood culture (gets taken in any patient with a fever)
  • Renal function
  • blood count - neutrophilia, haemolysis (E. Coli O157)
  • abdominal X-Ray/CT if abdomen distended, tender (Imaging can demonstrate dilatation of the large bowel)
26
Q

what are some differential diagnosis?

A
  • Inflammatory bowel disease (if diarrhoea more than 2 weeks and bloody)
  • Spurious diarrhoea - secondary to constipation
  • Carcinoma
  • Diarrhoea and fever can occur with sepsis outside the gut
  • lack of abdo pain/tenderness
    goes against gastroenteritis
  • no blood/mucus in stools
27
Q

What is the treatment of gastro-enteritis?

A

• Rehydration - iv or oral?

  • Oral rehydration with salt/sugar solution
  • iv saline

Iv in hospital

In community will depend upon oral rehydration

Glucose and salt together is better than just salt as the transport of glucose is linked to sodium across the cell wall

28
Q

what are the features of Campylobacter gastroenteritis?

A

Most common

Up to 7 days incubation so dietary history may be unreliable

Stools negative within 6 weeks

abdominal pain can be severe

<1% invasive

Post-infection sequelae - Guillain-Barre syndrome, Reactive arthritis

29
Q

what are the features of Salmonella gastroenteritis?

A

symptom onset usually <48 hrs after exposure

diarrhoea usually lasts <10 days

<5% positive blood cultures

20% patients still have positive stools at 20/52 - Prolonged carriage may be associated with gallstones

Post-infectious irritable bowel is common

30
Q

How is E.coli O157 spread?

A

Infection from e.g. contaminated meat or person-to-person spread (low incoulum)

31
Q

What does E.coli O157 cause?

A

Typical illness characterised by frequent bloody stools

Prominent bloody stools

Abdominal pain

Not much fever

32
Q

How does E.coli O157 cause problems?

A

E. coli O157 produces Shiga toxin (same toxin also produced by Shigella spp) (previously called verocyto- toxin) - Organism it self is not the problem, it’s the toxin

E. coli O157 stays in the gut but the toxin gets into the blood

toxin can cause hemolytic-uraemic (HUS) syndrome (haemolytic anaemia and renal failure)

33
Q

What are the effects of hemolytic-uraemic (HUS) syndrome and how are they caused?

A

HUS characterised by renal failure, haemolytic anaemia and thrombocytopenia. Treatment supportive - antibiotics NOT indicated

Toxin stimulates platelet activation and micro-angiopathy results

Micro-angiopathy haemolytic anaemia by clotting of the platelets in the blood vessels so the blood cells are squeezing through these platelet clots and becoming haemolysed

Lose platelets and get renal insufficiency and uraemia

General supportive measures required and no antibiotics needed and may make it worse

34
Q

E. coli rates

someitmes get spikes

A
35
Q

When should I give antibiotics?

A

Indicated in gastroenteritis for

  • immunocompromised
  • severe sepsis or invasive infection
  • chronic illness e.g. malignancy

Not indicated for healthy patient with non-invasive infection

Vast majority of patients don’t need antimicrobial treatment - Treatment all about maintaining hydration

36
Q

Summary:

  • Gastroenteritis is a common illness which can be diagnosed _______
  • A _______ of patients with gastroenteritis are admitted to hospital
  • The main stay of treatment is _________ and this can usually be oral rather than iv
  • A minority of patients require ________
A

clinically - Not dependent on microbiological conformation

minority

rehydration

antibiotics

Year 3 - infection (14 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions