deck 6 Flashcards
What syndromes could potentially cause a total body skin peeling with a sunburn-like rash in newborns?
Staphylococcal scalded skin syndrome, Staphylococcal TSS, and Streptococcal TSS
Which toxins are the major causes of Staph TSS?
TSST-1, enterotoxin B, enterotoxin C
Which toxins are the major causes of Staph Scalded skin syndrome?
exfoliative toxin A and B
General mechanisms of transmission (review)
aerosol, direct contact, sexual contact, vectors, fecal:Oral (water), food, endogenous, nosocomial
What is a flat, sunburn-like rash called?
macular erythroderma
What is a bumpy rash called?
papular
What is a flat, sunburn-like rash with bumps called?
maculo-papular
What is a rash with hives called?
urticarial
What is a rash with small fluid-filled sacs called?
vesicular
What is a rash with large fluid-filled sacs called?
bullous
What is a rash with fluid-filled sacs with yellow, white, or green pus called?
pustular
What is a rash with small rose-shaped spots called?
petechial
what usually causes the rose-shaped spots of the petechial rash?
blood vessel damage in gram-negative infections
What is a purple rash due to blood leaving the blood vessels called?
purpuric
What is a floor burn-like rash that eventually becomes a black scab called?
eschar
Which type of rash may be associated with menstrual TSS?
macular erythroderma
what type of rash is associated with chickenpox?
papular rash
what type of rash may be seen with staphylococcal impetigo?
pustular rash
What type of rash is associated with a cutaneous anthrax infection?
eschar
What is a primary pathogen?
A microbe that, when present in the host, typically causes illness
What is an opportunistic pathogen?
Often normal flora microbe that causes illness when the host is immune compromised.
What are the four types of primary pathogens?
exotoxemia, invasive extracellular, exotoxemia + invasive extracellular, invasive intracellular
Tetanus, Diphtheria, Cholera, TSS,Scarlet Fever fall into which category of primary pathogen?
exotoxemia
Haemophilus influenzae, Streptococcuspneumoniae, Neisseria meningitidis fall into which category of primary pathogen?
invasive extracellular
Staphylococcus aureus, Streptococcus pyogenes fall into which category of primary pathogen?
exotoxemia + invasive extracellular
Mycobacterium tuberculosis, Salmonella typhi, Listeria monocytogenes fall into which category of primary pathogen?
invasive intracellular
What are examples of the major categories exotoxins (review)?
ADP ribosylating enzymes, depurinating enzymes, cytolysins/cytotoxins, proteases, superantigens
T/F: Many exotoxins are referred to as A:B or B:B toxins, where A=active and B=host cell binding.
T
Where are many exotoxins encoded?
bacteriophages, plasmids, or pathogenicity islands
On what does immunity to exotoxin illnesses depend?
neutralizing antibodies
Why don’t people develop neutralizing antibodies to tetanus and botulism toxins during illness?
they are too toxic to be immunogenic
T/F: immunity to exotoxins always provides protection from illness?
F; immunity to some exotoxin provides protection, while immunity to others does not
Of what do vaccines against exotoxins consist?
toxoids that are biologically inactive forms of toxins
Some examples of vaccines against exotoxins (review)
diptheria, tetanus, and pertussis.
the virulence of invasive extracellular pathogens depends primarily on what two factors?
host attachment mechanisms and antiphagocytic capsules
T/F: invasive extracellular organisms usually invade hosts through the skin.
F; they usually invade through mucosal surfaces
T/F: invasive extracellular pathogens usually cause illness through extensive inflammation
T
On what does immunity to invasive extracellular pathogens depend?
opsonic antibodies to capsules or other cell-surface virulence factors
T/F: exotoxemia and invasive extracellular pathogens depend on both exotoxins and invasive properties.
T
T/F: exotoxemia and invasive extracellular pathogens are always highly inflammatory.
F; usually, but not always
On what does immunity to exotoxemia and invasive extracellular pathogens depend?
both neutralizing and opsonic antibodies
Do we have vaccines for exotoxemia and invasive extracellular pathogens?
NO.
In which immune cells are invasive intracellular bacteria able to survive?
PMNs, Macrophages, and B-cells
T/F: Invasive intracellular bacteria are highly inflammatory.
F; they usually induce granuloma formation instead of inflammation
On what does immunity to invasive intracellular pathogens depend?
direct T-cell killing or T cells activating macrophages to kill the pathogens
What type of vaccines are used for invasive intracellular organisms, and why?
live attenuated vaccines are used, because killed vaccines stimulate antibodies which makes the illnesses worse.
What is the correct immune response to Staph aureus?
must make both opsonic antibodies and neutralizing antibodies, or the host will die of delayed hypersensitivity
What is the correct immune response to Typhoid fever?
Must make a Th1 response activating macrophages for immunity to typhoid fever, because antibodies enhance typhoid
