Flashcards in An Infection Model Deck (76):
What does an infection model allow for?
A simplistic look at the progress of most infections
What does an infection model show?
How someone acquires an infection and what happens if they get one
What is the infection model?
The interaction between pathogen and patient leads to infection.
Infection → management → Outcome
What are the classes of pathogens causing disease?
What are the classes of fungi?
What are the classes of parasites?
What is the type and severity of an infection often influenced by?
Specific characteristics concerning the patient and their lifestyle
What person factors can influence the outcome of infection?
Why does age influence the type or severity of infection?
As age changes, so does the risk of acquiring particular infections
Give an example of age changing the risk of acquiring particular infections
Newborns are prone to developing meningitis infections from E. Coli
At 3 months - 3 years, they are more likely to develop streptococci meningitis
There is increased risk developing meningitis again in the late teens
Why are elderly patients at increased risk of infection?
In elderly patients, there is more chance of co-morbidities, increasing the risk of infection
Why does gender influence infection?
Some infections are more common in one gender than the other
Give an example of a infection that is more common in one gender than the other
UTIs are more common in women than men
Why are UTIs more common in women?
Due to the anatomically different positions of the anus and the urethral opening
How can physiological state affect infection?
Changes in physiological state, especially hormone levels, can put a person at more risk of infection
Give two examples of when physiological state can change the risk of infection
Different stages of the menstrual cycle
What effect does pregnancy have on infection?
During pregnancy, there are hormone changes that put women at risk of infection
What effect does different stages of menstrual cycle have on infection?
During different stages of the menstrual cycle of pH of the vagina can become raised allowed overgrowth of candida (thrush)
How can pathological state affect infection?
Some pathologies can cause people to become immunocompromised
Medical treatments due to other pathologies can increase the chance on infection
What pathologies can cause people to become immunocompromised?
Give an example of a genetic disorder that can cause immunocompromisation
What medical treatments can increase the chance of infection?
Why does chemotherapy and immunosuppressants increase the risk of infection?
Cause the patient to become immunocompromised (obvs the answers in the name lol)
Why do catheters increase the risk of infection?
They breach the primary immune system and can allow the skin commensals to become pathogenic
Give an example of an infection that can occur as a result of a catheter
Staphylococcus epidermidis can cause endocarditis
How can surgery increase the risk of infection?
Can allow infectious agents to bypass the body's primary immune system
How can social factors affect the risk of infection?
Poor social and living conditions are associated with increase risk of infection
Give an example of a social factor that can increase the risk of infection
Children in nurseries often have dirty hands, so when one child has an infection, it often spreads to other children and the parents
In what ways can time be considered when looking at infection?
Give an example of where calendar time can affect infection
Flu and norovirus infections are more common in winter
What is meant by relative time in infection?
Time relative to other cases
Give an example of an infection where relative time is important to consider
When is relative time regarding infection useful?
When trying to diagnose
In what way can place be considered when looking at infection?
Why is the current place important when considering infection?
Environment can affect nutrition and diet
Infections can spread in hospitals if infection control is poor
Why is it important to ask patients about recent locations?
Must know about recent travel as some infections are more prevalent in some countries than others, which may help identify the cause of infection
What does the mechanism of infection vary depending on?
The type of infection
What are the potential mechanisms of infection?
Contiguous (direct) spread
What is meant by contiguous spread?
From one part of the body to another
What should be sterile in the body?
Anything under the skin, including the blood
Give an example of when inoculation with infection could occur
What is haematogenous spread?
Any spread through the bloodstream
What happens in ingestion of an infectious agent?
Eating or drinking of contaminated items
What is ingestion of pathogenic organisms often part of?
What happens in inhalation of pathogenic organisms?
Breathing in droplets or aerosols
Where is vector transmission important?
Worldwide in the spread of malaria, and more recently the Zika virus
Why is vector transmission of less concern in the UK?
It is not very common
What is vertical transmission?
Transmission from mother to infant
How can vertical transmission occur?
Can be transmitted across placenta
From vagina if membranes are broken
At time of delivery
What do the symptoms of infection occur due to?
A complex interaction of a range of factors
What factors interact to determine the symptoms of an infection?
Attachment can lead to toxin production and interaction with host defences.
Interaction with host defences can lead to inflammation.
Inflammation, interaction with host defences, and toxin production can lead to host damage
What are the types of toxins produced by bacteria?
What releases exotoxins?
What do exotoxins do?
Released into environment to aid reproduction
When are endotoxins produced?
When bacteria break down
What are endotoxins?
A component of the cell wall of gram -ve bacteria
What can host damage occur due to in infection?
Directly due to microbe actions
Indirectly via damaging inflammatory responses
What will management of a patient vary depending on?
Causative agent of an infection
What does management of an infection consist of?
What does diagnosis of an infection consist of?
What is the purpose of diagnosis of an infection?
Where the infection is
What caused the infection
What are the categories of treatment for infection?
What are the specific treatments of infection?
What are the categories of antimicrobials?
Why may surgery be required in the treatment of infection?
Remove necrotic tissue from an abscess
Dead space removal
Give an example of when drainage would be required in infection
Chest drain of pus in pleural space
What happens in debridement?
Cut away infected tissue
Give an example of an infection where debridement may be required
What is the problem with debridement surgery?
It can be mutilating
Why is dead space removal sometimes required in infection?
Removes space for bacteria to divide into
Why is the use of surgery in infection management decreasing?
Some of the things that used to be treated with surgery can now be treated with drugs
What are the supportive treatments for infection?
What symptom relief can be given in infection?
Give an example of where physiological restoration is very important in infection
Where can infection prevention take place?