Unit 12 Miscellaneous Body Sites Flashcards
List two of common skin contaminants seen in superficial wound specimens
Diphtheroids Coag-negative Staph Alpha hemolytic strep Nonhemolytic strep Propianibacterium spp Bacillus spp
A direct gram stain is performed on all wound, tissues, and body fluids. Why? What is reported out on the direct smear on these culture types?
To determine the quality of the specimen. Ideally: Many PMNs and no/rare/few SECs
To compare to culture: are all organisms recovered?
What is the purpose of the thioglycollate broth?
To recover fastidious organisms or small amounts
Eikenella: description
“Frosty” colony, small thin GNB, , ox+
Bacillus species: description
Large ground glass colony, large GPB, Cat +
Lactobacillus: description
Alpha, GPB in chains, Cat =
Capnocytophaga: description
Glistening “sweaty” colony, long GNB w/ tapered ends
Pasterurella: description
Large gray, GNB, Cat+, Ox+, NG on MAC
Acinetobacter: description
Mucoid, “Mauve” NLF on MAC, GNB, Short fat GNB, Ox=
Actinomyces: description
Small gray white nondescript, sometimes molar tooth; better anaerobic; cat -, paleo GNB
Brucella: description
Tiny on BAP/CHOC at 3 days, faint staining GNC or GNCB
Rothia: description
Gray sticky nonhemolytic on BAP; GPC clusters, Cat variable
Listeria: description
Gray soft beta on BAP; GPB; Cat +
Propionibacterium: description
Pleo GPB; anaerobe that may break through on aerobic plates; Cat +, can be beta, If indole + P.acnes
Culture media for Wounds and abscesses
BAP
MAC
CHOC
PEA (extremities and sources below the diaphragm)
How to inocculate: order
Least selective–> most selective
Potential pathogens wound/abscess
S. aureaus Beta hemolytic strep Group D strep S. anginosus Enterococcus Enterobacteraciae Pseudomonas/NLFs Eikenella corridens Pasteurella multocida Anaerobes Yeasts Actinomyces
Susceptibility testing on which organisms for wound/abscess ?
S. aureus Enterococcus Enterobacteraciae Ps. aeruginosa Other nonfermenters
Wound/abscess: for alpha and gamma strep, what needs to be ruled out?
Group D
Wound/abscess: for bacillus spp, what needs to be ruled out?
B. anthracis
Wound/abscess: What 4 general groups only require limited ID as likely skin contaminants?
Diphtheroids
Coag-Neg staph
Viridans strep
Bacillus spp
What could a mixed culture indicate?
1) Contaminated specimen
2) Normal flora for site of collection
3) Polymicrobic infection, may be mixed aerobes+anaerobes
What is the rule of 3?
Perform ID and susceptibilities on UP TO 3 pathogens
More than 3 semi quantitate all and list descriptive ID