Flashcards in Lecture 8 Deck (52)
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1
Define Cl Tetani
a soil dwelling saprophytic organism- spores wide spread in soil- slender thin rods with tennis racket appearance
2
Portal of entry for Cl tetani
skin-through wound-like nail prick, road accidents where there is contamination of mud, skin popping in drug addicts
3
WHat does Cl tetani cause?
Tetanus- lock jaw
4
Can Cl tetani cause infection in newborns?
can occur through umbilical cord cutting, through circumcision in developing countries-- spores germinate at the wound
5
What do vegetative cells of Cl Tetani produce?
exotoxin which spreads through nerve fibers to spinal cord
6
What does exotoxin block release of?
glycine- inhibitory neurotransmitter- in spinal synapse causing muscle spasms (tetany)
7
Is vaccine effective for Cl Tetani?
YES- because only one Ag variety (sero type)
8
How is Tetanus defined?
characterized by spasm of skeletal muscles starting from face, hardening of facial muscles results in grim face
9
What is the hardening of facial muscles in Cl Tetani known as
Risus sardonicus
10
What is spasm of muscles of mastification from Cl Tetani lead to?
Lock Jaw known as trismus
11
What does spasming of back muscles result in?
Arching of back known as Opisthotonus
12
What type of poisoning resembles the condition of Cl Tetanis
strychnine poisoning
13
How do you treat tetanus?
Tetanus antitoxin serum to neutralize unbound toxins, penicillin and metronidazole may be useful- maintain adequate airway, muscle relaxants like valium
14
How do you prevent tetanus?
toxoid vaccine (DTaP) is available
15
What is the natural habitat of Cl Botulinum?
soil- spores are found in soil, found in contaminated vegetables, alkaline vegetables, spores germinate in anaerobic conditions
16
What is an indication that bacteria may be growing in canned vegetables?
swollen/bloated can tins
17
How do you get the Cl Botulinum toxins?
ingested- absorbed from gut and carried to neuromuscular junction
18
What does Cl Botulinum cause in a person and how?
flaccid paralysis- blocks release of acetylcholine- can cause paralysis of ocular muscles causing vision problems- respiratory failure when pharyngeal muscles are relaxed
19
Will Cl Botulinum present with a fever?
NO
20
Can an infant get Cl Botulinum?
yes- contaminated honey- spores germinate in gut and cause silent death of an infant
21
Treatment for Cl Botulinum?
Trivalent antitoxin available- antitoxin made from horses and given with respiratory support
22
Prevention of Cl Botulinum
The tosin is relatively heat labile so boiling vegetables/food will inactivate toxins
23
What are some medical uses of Cl Botulinum?
to remove wrinkles on forehead or to relieve spastic torticollis (wry neck)
24
Describe Cl Perfringens
Gram + rod shaped, anaerobic spore forming bacterium
25
What 2 diseases can Cl Perfringens cause?
Gas gangrene and food poisoning
26
Describe gas gangrene
vegetable forms are members of normal flora of colon and vagina- spores are found in soil
27
Most common mode of contamination of Gas gangrene
wound contamination with soil/mud (war wounds, automobile accidents, septic abortion
28
How is the gas gangrene produced?
organism grows in traumatized tissues, produced alpha toxin which causes necrosis of muscle and RB cells and enzyme degradation produces gas in tissues
29
Results of Gas gangrene
pain, edema and cellulitis, crepitations, massive hemolysis, jaundice, renal failure, shock and death - high mortality rate
30
