Ch. 26 - Corynebacterium

Question 1

Corynebacterium

Answer 1

Aerobic G+b
coryneform bacilli (club) 
CAT +
Ferment carbs
Non-motile

Metachromatic granules

Colonize human skin, URT, GI, GU
Opportunistic pathogen

Question 2

Corynebacterium diphtheriae

Answer 2

Pleomorphic G+B with metachromatic granules

4 biotypes: belfanti, gravis, intermedius, mitis

Diphtheria toxin - major virulence
exotoxin produced at infection site, spreads thru blood
org doesn’t need to be in blood to cause disease

Humans only known reservoir

Question 3

Corynebacterium diphtheriae disease

Answer 3

Diphtheria: clinical presentation is determined by site of infection, immune status of patient, virulence of organism

• Respiratory diphtheria: exudative pharyngitis that develops into thick pseudomembrane (adheres to underlying tissue), systemic illness in severe cases: myocarditis, congestive heart failure, cardiac arrhythmias
• Cutaneous diphtheria: acquired through skin contact, papule develops turning into chronic non-healing ulcer

Question 4

Corynebacterium jeikeium

Answer 4

Aerobic G+b

Opportunistic pathogen in immunocompromised

Question 5

Corynebacterium urealyticum

Answer 5

Aerobic G+b

Urinary tract pathogen

Urease + –> makes urine alkaline –> renal stones