Bacteria SM Flashcards
Bacillus Anthracis
1) what “scene” was it?
2) what gram stain
3) What does it characteristically cause?
4) what might you see microscopically?
5) what kind of microbe is this? what is this made of? what is it capsulated with?
6) how much oxygen does it require?
King Anthra’s Axe
Gram +
Black Eschar with erythematous ring –> ring of fire around the vikings
rods in chains –> boats in background
encapsulated + made of protein –> leather armor
Poly - D Glutamate
Obligate Aerobe –> Air bellow
Bacillus Anthracis
1) what “scene” was it?
2) what is produced that allows them to survive in poor environments?
3) what are the two toxins associated with it and what do each do?
4) how could someone get this historically?
5) if someone inhales this, what can it move to and progress to? What do you see on Xray that’s characteristic of this?
King Anthra’s Axe
spores –> walnuts
EF toxin –> increases cAMP intercellularly –> causing fluids to go into extracellular space –> edema –> inhibiting host defenses and preventing phagocytosis…… Viking CAMP
Lethal Factor (LF) –> exotoxin that acts as a protease and cleaves MAP Kinase (signal transduction protein responsible for cell growth) –> leads to NECROSIS and BLACK ESCHAR –> burning the map
Sheep handlers –> wool sorters disease, spores can get into the wool and hide of animals and persist –> inhaled –> pulmonary anthrax –> sheep in the picture
pulmonary anthrax can move to mediastinal lymph nodes progressing to Hemorrhagic Mediastianitis –> WIDENED mediastinum on CXR –> CXR sail with widened rope in the middle
Bacillus Cereus
1) what “scene” was it in?
2) how much oxygen does it require?
3) what can it do similar to Bacillus Anthracis?
4) when is it commonly associated with historically?
King Anthra’s Axe
aerobic (air bellow)
spore forming (walnuts)
associated with vomiting from food poisoning related to reheated fried rice –> holding fried rice close to fire
Clostridium Tetani:
what “scene” was it?
What gram stain is it?
What kind of bacteria is it?
What oxygen type does it prefer?
How does this infect someone?
what are the two main symptoms associated with this?
Rhesus Research Revolution
gram + –> violet hue
SPORE FORMING –> walnuts
obligate anaerobes –> gasmasks on researchers
found in the dirt and enters the body through a puncture wound –> rusty nails, pots of soil, barbed wire.
spastic paralysis leading to rigidity and Rhesus Sardonicus –> means evil grin and accompanies lock jaw (tense masseter muscles) –> rhesus monkeys
Opisthosomas –> monkey in exaggerated arching back position (another common symptom)
Clostridium Tetani:
1) what “scene” is it?
2) explain the pathogenesis (what kind of toxin is it?)
3) why does someone get the spastic paralysis?
4) what kind of vaccine is it and what does it target?
Rhesus Research Revolution
puncture wound by nail or barbed wire with tetany spores on it –> spores embed in flesh –> releases tetanus toxin, WHICH IS A PROTEASE (scissors) (which causes all symptoms, NOT the bacteria) –> this travels RETROGRADE through motor axons to the spinal cord
this will cleave SNARE and inhibit exocytosis of the neurotransmitters GABA and Glycine into the synapse from the cells they’re housed… “Renshaw Cells”
they get the spastic paralysis because GABA and glycine are inhibitory neurons, so inhibiting the inhibitory neurons mean uncontrolled firing of motor neurons.
Toxoid –> toxin conjugated to protein –> antibody response to the TOXIN, not the organism.
Clostridium Botulinum:
1) what’s the scene?
2) how do adults get it? what’s in the question stem usually?
3) what kind of organism is it? what kind of oxygen does it need?
4) what are the THREE clinical manifestations you’ll see with this? what is it often confused with?
Robotulism
transmitted by improper canning of food –> allows the spores to flourish in the anaerobic environment producing a heat-stable toxin (robot cans) –> “a family presents with same neural symptoms”
Spore former + Obligate Anaerobe
Ptosis/diplopia, Flaccid paralysis (can’t keep body upright), DESCENDING paralysis (goes from superior to inferior) –> don’t confuse it with Guillen Barre syndrome which is ASCENDING paralysis.
Clostridium Botulinum:
1) what’s the scene?
2) what is it targeting and how does it work?
3) how does this differ from tetani?
4) what does this look like in a baby? how does the baby often get it?
Robotulism
Cleaves SNARE (similar to tetany), but attacks motor neurons that RELEASE ACh, inhibiting motor neuron release, leading to flaccid paralysis.
doesn’t attack Renshaw cells, attacks ACh stuff.
Floppy Baby Syndrome (same neural presentation) –> Babies have a weak gut immunity so they ingest the spores COMMONLY from HONEY –> it forms the toxins IN THE BODY, not preformed like adults.
Clostridium Difficile
1) what was the scene?
2) what usually causes it and where does it happen?
3) why do antibiotics create this infection?
4) What are the two exotoxins associated with it? explain each
5) what is Clostridium Difficile also called?
field trip to the chocolate factory
poorly washed hands + clindamycin –> NOSOCOMIAL diarrhea
antibiotics wipe out normal flora making patients immunocompromised and able to be colonized by C diff.
Exotoxin A –> Binds to the BRUSH BORDER of the intestine and causes CELL DEATH AND WATERY DIARRHEA (woman brushing apple, exotoxin A is for Apple
Exotoxin B –> B is for black licorice –> there’s a kid eating and DEPOLYMERIZING ACTIN looking black licorice –> leads to enterocyte death, necrosis, and a YELLOWISH GREY EXUDATE that forms a pseudomembrane that covers the colonic mucosa
Pseudomembranous colitis –> because of exotoxin B
Clostridium Difficile
1) what was the scene?
2) how do we detect it?
3) what gram stain is it? what oxygen preference does it have?
4) what’s the main treatment?
Field trip to the chocolate factory
Assay to detect the TOXIN, not the microbe, in the stool.
Gram +, Obligate anaerobe (gas mask)
Oral Vancomycin, NOT IV –> to hit the colon.
Clostridium Perfringes
1) what’s the scene?
2) what is it usually caused by? 2 things. why?
3) What does this infection cause? 2 diseases
Private Ringen’s Motorcycle Accident
motorcycle accidents and deep penetrating military wounds –> because large amounts of flesh are exposed to dirt and dust (motorcycle accident and private on the ground)
Gas Gangrene (or clostridial myonecrosis) –> gas is produced under the tissue and has a cracking sound on palpation (crepitus) –> (Gas coming from motorcycle)
SLOW ONSET diarrhea due to spores needing to reproduce.. this is UNIQUE because all other spores need to form outside of the body, this forms INSIDE the body. (slow sign knocked over)
Clostridium Perfringes
1) what was the scene?
2) what causes the gas gangrene? what is another name for it?
3) in what pattern does this lysis happen?
4) gram stain? preference for oxygen?
Private Ringen’s Motorcycle Accident
alpha toxin (or lecithinase) effects the lipid bilayer –> lyses RBCs (clothespins)
double zone of hemolysis –> this is unique!! (broken tomatoes)
gram +, obligate anaerobic (gas mask, purple hue)
