Diptheria Flashcards
Diphtheria is a bacterial URTI
T/F
T
Diphtheria
Aetiological Agent:
•________________
Corynebacterium diphtheriae
Diphtheria
Characteristics
• Gram __________
• Sporulating or Non-sporulating
• Encaspulated or Non-encapsulated
• Motile or Non-motile
•coccus or bacillus
positive
Non-sporulating
Non-encapsulated
Non-motile
Bacillus
Diphtheria
_______ are the only known reservoir
Humans
Diphtheria
Transmission:
• Spreads via _________ and _______
•____________ is important in transmission
air droplets and direct contact
Asymptomatic carriage
Diphtheria
Incubation period of _____-_____
2-5 days
Morphology of diphtheria
______ shaped
________ granules giving a _______ appearance
Club
Metachromatic
beaded
Morphology of diphtheria
______ lettering appearance, because the ____________ or at _______ to each other
Chinese
rods lie parallel
acute angles
Morphology:
On blood agar, the diphtheria colonies are (small or large?) and ____color with ______ edges
On tellurite blood agar, it produces _____________ colonies
Small; gray ; irregular
brown or black
__________ media for corynebacterium diphtheria
Loeffler’s serum
Biotypes of Corynebacterium Diphtheriae
List 4
Gravis
Intermedius
Mitis
Belfanti
Diphtheria Virulence factors
Diphtheria toxin
• Heat ______
• Has _________ Fragments
labile
A and B
Diphtheria Virulence factors
Diphtheria toxin
Fragment A: inhibits _______________
Fragment B: binds to ______ and ___________________________ via _______________
polypeptide chain elongation
receptors
allows the rest of the toxin (Fragment A) to enter the cell
receptor mediated endocytosis
Pathogenesis of Diptheria
Diphtheria toxin gets into Mucous membranes
Destroys _______ and causes _______ that leads to ______
_______+ _______+ _______+ _______ forms a __________ over the tonsils, pharynx and larynx
_______________ become enlarged.
membrane epithelium
inflammation; necrosis
Necrotic epithelium + Fibrin + red and white cells
grayish pseudomembrane
Regional lymph nodes
Pathogenesis
• Toxin can also cause distant damages, particularly to;
________
___________
_________
_________
____________
Heart muscle
Liver
Kidneys
Adrenal Glands
Nerves (demyelination)
• diphtheriae does not need to be toxigenic to establish localized infection but nontoxigenic strains do not yield the localized or systemic toxic effects.
Tf?
Clinical Features
————
Fever
Dyspnea (due to the _________)
_______
______itis
______________
Cutaneous infection causes _________
Sore throat
pseudomembrane
Suffocation
Card
Motor Neuropathy
indolent ulcers