3. An infection model Flashcards
Give the 2 essential things needed for an infection
The pathogen and the patient
In the mechanism of infection what role does management play
Usually there is self management of infection (the immune response) however in cases when self response isn’t efficient you may need to introduce medical response in the form of drugs
What are the 4 main types of pathogens
prokaryotes: Virus Bacterium eukaryotes: Fungus (yeast vs mould) Parasite (Protozoa va helminth)
What factors of a patient can effect risk of infection?
Person
1. Age
As you get older your immune system weakens
The elderly and younger children are more susceptible to disease
2. Gender
Women and men have different anatomies which can affect their risk of infections.
E.g women are more likely to get UTIs than men
3. Physiological state
For example pregnant women are more exposed and more at risk of disease
4. Pathological state
This refers to long term conditions and co-morbidities
E.g having diabetes can increase your risk of peripheral arterial disease (PAD)
5. Social factors
This refers to occupation, hobbies, contact with animals, tattoos, use of IV drugs etc
Time
1. Calendar time
Certain infections, colds etc are more prevalent during certain parts of the year
2. Relative time
This refers to incubation periods, different infections and pathogens will have varied incubation periods
Place 1. Current Their current environment e.g hospital 2. Recent If they've been in a different environment in the past E.g holiday to an exotic country
What are the 7 possible mechanisms of infection
Contiguous spread(spreading over body, direct) Inoculation Haematogenous (blood born) Ingestion Inhalation Vector (3rd party transmission) Vertical transmission (mother to child )
Describe the effect that attachment of the pathogen has on the host cells
- Attachment of the microorganism to the host via mechanism specific to the pathogen
- attachment can cause to produce toxins to destroy cells of the host and cause host damage
- attachment can also cause interaction with host defences which can cause inflammation aswell as host damage
What is pus
collection of neutrophils
Describe the ways in which host damage can occur
- accumulation and action of toxins produced by pathogen
- inflammation and swelling in the affected tissue can cause damage to host cells
- interaction of pathogen with host defences can also result in damage to host cell
Exaplain what is involved in the management of an infection
Where the patient presents with symptoms
• First a HISTORY is taken (e.g work, occupational, travel, drug etc).
• Next a physical EXAMINATION can be taken to see the physical presentation of the suspected infection.
• INVESTIGATIONS can be carried out to help make a diagnosis, these can be specific or supportive
• Once the diagnosis process has been carried out TREATMENT can ensue.
• This can be SPECIFIC or it can be SUPPORTIVE
• Infection prevention within HOSPITALS and the COMMUNITY are also very important to reduce the risk of preventable infections.
What is the difference between specific and supportive management
Specific: to figure out the exact pathogen, what drug will treat it directly e.g using a narrow spectrum antibiotic to kill the specific microorganism carrying infection
Supportive: is there something wrong? to determine whether it is an infection. If so treat generally, general antibiotics or even just pain management and rest or surgery to remove an infected limb
What is source control?
Removal of the source of infection e.g amputation of an infected leg to prevent the infection spreading.
describe the specific treatments for infection
1) antimicrobials
2) surgery
- drainage
- debridement
- dead space
What do the following terms mean: drainage, debridement and dead space removal
Drainage: drain puss away is key in infection management
Debridement: removal of dead/dying tissue which could act as nutrients for the infection if bacterial
Dead space removal: this is done through surgery to ensure that the empty space of removal doesn’t just fill with blood and etc which can be very atttractive to bacteria.
What is the aim of infection prevention in the hospital and the community?
It’s done to prevent infection transmission to
• Other patients
• Staff
• Other contacts
What is the outcome in infection management ?
The aim of this branch of medicine is always to cure, however sometimes that’s not possible.
The disease may to be too complex and the patient can die or it’s not possible to cure the patient so they are left with a chronic infection (e.g HIV) and sometimes disability.
