Unit 9: Anaerobes Flashcards
What are the two primary groups of anaerobic GPCs?
Peptostreptococcus
Anaerococcus
What do P. anaerobius and B. dentium have in common and how would you differentiate them?
Both indole and Nitrate reduction NEG
P. anaerobius is SPS disc SS
What is the 2nd most common group of anaerobes ?
GPCs
How would you treat P. anaerobius?
Treated with penicillin G and cephalosporins
Habitat of Veillonella?
-Normal flora of mouth and gut
What would you do if the Vancomycin disk is sensitive but you had a gram stain with GNC?
Redo gram stain, you probably overdecolorized
What is a common cause of blood culture contamination?
Propionibacterium acnes
Propionibacterium acnes: habitat
-Normal skin flora
What result would give a presumptive ID of Propionibacterium acnes?
A GPB that is Indole POS
Why would you perform a Nitrate test on presumptive P. acnes?
To rule out C. diff. P. acnes is POS
Eubacterium lentum: habitat
Normal flora of intestinal tract
What are significant test results for Eubacterium lentum? What does it need to be differentiated from and how?
- POS catalase so Differentiate from Propionibacterium w/ gram stain; E. lentum=small GPB and P. acnes is pleiomorphic
- Colistin R
- Very little biochemical activity
What genus produces sulfur granules?
Actinomyces
What is the main issue caused by Actinomyces species in general?
problems with IUDs
Actinomyces israelii: habitat
Normal flora of mouth
Are Actinomyces species generally Nitrate production pos or neg?
POS
Which Actinomyces is Nitrate NEG?
A. meyeri
How would you differentiate A. Israelii and A. naeslundii? And why is it necessary?
Both are Nitrate POS Actinomyces species and A. Israelii is always able to hydrolyze esculin while A. naeslundii is variable.
A.naeslundii is urease POS
How would you differentiate A. vicosus and A. naeslundii? And why is it necessary?
Both are Nitrate POS Actinomyces species that are urease POS
A. vicosus is catalase POS
A nitrate POS and catalase NEG anaerobic GPB: What are the possibilities and how to you differentiate?
A. israelii- can hydrolyze esculin
A.naeslundii-Urease POS
A.odontolyticus-neither
What is the only Actinomyces that is catalase POS?
A. vicosus
A nitrate POS and catalase POS anaerobic GPB: What are the possibilities and how to you differentiate?
P.acnes- pleomorphic
E. lentum- small GPB
A. vicosus- Urease POS
What are the 5 Actinomyces species we care about?
A. israelii A.naeslundii A.odontolyticus A.vicosus A. meyeri