Natural History of Infection Flashcards
(36 cards)
What is an endogenous infection?
An infection caused by an infectious agent already in the body, but has previously been latent or dormant
What is an exogenous infection?
An infection resulting from invasion and multiplication of pathogenic microorganisms in a bodily part or tissue
Where is an endotoxin found?
On Gram-negative bacteria
What is an endotoxin?
The lipopolysaccharide on the outer membrane that can cause disease and produce an inflammatory response
What is an exotoxi?
A toxin secreted from the micro-organism which disrupts cellular mechanisms
What is a superantigen?
One that directly stimulates CD4+ T cells
What do superantigens cause?
A massive inflammatory response
What is the reservoir?
The natural habitat for the organism in which it can propagate
What is the immediate source?
Habitat from which the organism is transmitted and which it must survive.
Location of organism between reservoir and susceptible host
What happens once an organism has passed from the immediate source to the susceptible host?
Multiplication of the organism, and associated damage
What viral syndromes are common?
- Viral respiratory infection
- Viral childhood exathems (rashes)
- Viral gastroenteritis
- Viral hepatitis
- Human papillomavirus
- Herpesvirdae
Give 3 examples of childhood exathems
- Measles
- Chickenpox
- Rubella
What is the most common cause of viral gastroenteritis?
Rotavirus
What are some less common causes of viral gastroenteritis?
- Adenovirus
- Norwalk virus
- Astrovirus
What are the types of viral hepatitis?
- Enteric
- Blood or body fluid
What type of hepatitis is enteric?
Hep A
What types of hepatitis are blood or body fluid related?
B, C and D
What does human papillomavirus cause?
- Cutaneous anogenital warts
- Oncogenic role in development of cervical cancer
What are the herpresvirdae?
Ubiquitous family that give rise to persistent latent infections that can be reactivated years later
What are the main patterns of disease seen in bacterial and viral infections?
- Toxin mediated
- Acute pyogenic infections
- Sub-acute infection
- Chronic granulomatous infections
What is the simplest method of disease?
Toxin mediated
How can a toxin mediated disease be reproduced?
Administration of the toxin alone
Why can administration of the toxin alone be clinically advantageous?
Adaptive immunity can produce anti-toxin antibodies against the infection
Where is the pathology often with toxin mediated infections?
Distant from the site of bacterial growth
