Diphtheria: Corynebacterium diphtheria

Question 0

Diphtheria: Corynebacterium diphtheria

Virulence factors

Answer 0

Diphtheria toxin: phage mediated
Produced at site of infection
Disseminates through the blood
Receptors on heart and nerve cells

Question 1

Diphtheria: Corynebacterium diphtheria

Characteristics

Answer 1

Gram positive, club shaped
Nonmotile
Catalase positive
Cysteine tellurite blood agar

Question 2

Diphtheria toxin: mode of action


Answer 2

same as P. aeruginosa Exotoxin A
ADP-ribosyl transferase
Inactivates elongation factor 2
Inhibits host protein synthesis

Question 3

Diphtheria: Corynebacterium diphtheria

Modes of transmission

Answer 3

Respiratory: transmission respiratory aerosols
Cutaneous: transmission skin contact

Question 4

Diphtheria: Corynebacterium diphtheria

Symptoms

Answer 4

Formation of thick gray pseudomembrane

Malaise, sore throat, fever, exudative pharyngitis

Question 5

Diphtheria: Corynebacterium diphtheria

Potential complications

Answer 5

Myocarditis

Neurotoxicity

Question 6

Diptheria Diagnosis

Answer 6

Selective agar: cysteine tellurite blood agar
Tinsdale agar
Tellurite: grayish black colonies
Cysteine: brown halos surrounding colonies

PCR