Microbiology-Neurotoxins Flashcards Preview

MSK I > Microbiology-Neurotoxins > Flashcards

Flashcards in Microbiology-Neurotoxins Deck (20)

What are the special characteristics of strict anaerobes?

They can't use oxygen as an electron receptor, they can't break down H2O2 and superoxides accumulate in the presence of oxygen.


What diseases are caused by Colostridia?

Botulism, tetanus, gas gangrene, food-poisoning, CDAD (C. Diff) and pseudomembranous colitis


What type of bacteria is Clostridia?

Gram + rods, spore formers


What are the three different flavors of botulism?

Food, wound and infant (most common)


A mother brings a baby to see the doctor and is diagnosed with floppy baby syndrome. You decide to treat the baby with medication. What medication do you give?

A heptavalent anti-toxin. Botilinum toxin has 7 distinct serotypes, if you don't know the serotype treat them all.


What are the most common serotypes of botulism?

Types A, B and E.


Why does grandma boil green beans when she cans?

She is terrified of botulism because it doesn't get killed by her stomach when she eats it, so she boils it for 20 minutes.


Why do they call botulism poisoning in a baby floppy baby syndrome?

It interferes with ACh release at the neuromuscular junction and causes flaccid paralysis.


What are the two components of the botulinum toxin?

A = enzymatic active part and B = binding component


What metal could you eliminate from a cell to limit destruction by BoNT?

Zinc. It must have zinc in order for the enzymatic portion to function


How does botox get rid of wrinkles?

It relaxes the muscles in the skin


What are typical symptoms of someone who has ingested food-borne botulin toxin?

No fever, dry mouth, difficulty swallowing, visual disturbances, speech difficulties and descending paralysis. Although it was ingested, they will not have digestive symptoms.


How do most deaths occur in botulin toxin poisoning?

Respiratory paralysis or cardiac arrest.


Why are babies more likely to get botulism?

Spores are more likely to germinate in their digestive tract than in adults. This is why you don't feed babies honey, it has spores in it.


What is babyBIG?

Human antitoxin antibodies against toxins A and B from volunteers that were injected with inactivated botulin toxoid


A mother brings her child to see you. The country she comes from commonly ties horsehair around the umbilical cord during birth. The child is having muscle spasms. How are these spasms produced?

Tetanus toxin cleaves VAMP (synaptobrevin) and prevents release of neurotransmitter glycine from inhibitory neurons in spinal cord, resulting in continual muscle contraction.


Why is stepping on a nail a risk for tetanus?

Spores are introduced into the wound by the nail. Other organisms in the wound may make the environment more anaerobic so the bacteria can make the toxin. The toxin then travels to the nerves.


What are the clinical presentations of tetanus?

Lockjaw, stiffness of the neck and respiratory failure.


How do you treat tetanus?

Antitoxin stops the toxin but does not stop the symptoms. You must treat the symptoms, nerve recovery is extremely slow.


If you haven't been immunized and have a very dirty wound what can you do to prevent tetanus?

TIG (human tetanus immune globin as passive immunity therapy) and metronidozole which inhibits growth of anaerobes.