You are reading culture plates today and identifying pathogens that grow from patient samples.
Which two pieces of information are absolutely critical in determining which additional tests must be done to identify the pathogen?
a) Appearance on charcoal agar
b) Endospore Stain
c) Gram Stain
d) Oxygen sensitivity
A 10 year old has a wound on the arm that the physician suspects is infected.
Upon culture, you see small white colonies growing on blood agar as well as chocolate agar.
You gram stain the colonies to find that they are gram positive cocci.
Which test will you perform first?
c) lactose fermentation
You have isolated catalase positive gram positive cocci from a wound culture.
Which test will you perform next?
b) P disc, containing optichin
c) A disc, containing bacitracin
You are working on a sputum culture.
You see mucoid alpha hemolytic colonies that number many more than the normal flora present.
The gram stain of the colonies shows gram positive cocci that are in lancet shaped pairs.
Which test will you do?
a) P disc, containing optichin
b) A disc, containing bacitracin
d) acid fast staining
You are working up a throat culture.
Standard procedure in plating throat cultures in your lab includes dropping an A disc near the initial inoculum in the first quandrant when streaking the specimen.
You examine the blood agar plate and see moderate normal flora and many beta hemolytic colonies that do not grow up to the A disc.
The beta hemolytic colonies are catalase negative gram positive cocci.
Which pathogen is in this throat culture?
b) Staphylococcus aureus
c) Streptococcus pyogenes
d) Staphylococcus epidermidis