lab d Flashcards
What is the primary purpose of blood culture?
To detect and identify microorganisms in the bloodstream.
What type of media is used in Castaneda’s biphasic blood culture method?
BHI broth and agar.
True or False: Blood culture can only detect bacterial infections.
False.
What does BHI stand for in BHI broth?
Brain Heart Infusion.
Fill in the blank: Castaneda’s biphasic media consists of ______ and agar.
BHI broth.
What is the significance of using biphasic media in blood cultures?
It allows for both aerobic and anaerobic growth of microorganisms.
Multiple Choice: Which of the following is NOT a component of BHI broth? A) Beef extract B) Peptone C) Glucose D) Sodium chloride
D) Sodium chloride.
What is the incubation temperature for blood cultures?
Typically 35-37 degrees Celsius.
How long should blood cultures be incubated before considering them negative?
At least 5 to 7 days.
True or False: The presence of bubbles in the broth indicates contamination.
True.
What type of specimen is primarily used in blood cultures?
Whole blood.
What is the role of agar in Castaneda’s biphasic media?
To provide a solid surface for colony growth.
Fill in the blank: Blood culture is crucial for diagnosing ______ infections.
Systemic.
What is the recommended volume of blood for adult blood cultures?
10 to 20 mL.
Multiple Choice: Which of the following pathogens can be detected by blood cultures? A) Fungi B) Viruses C) Protozoa D) All of the above
D) All of the above.
What is the purpose of subculturing from blood cultures?
To isolate and identify specific microorganisms.
True or False: Anaerobic bacteria can be detected using Castaneda’s biphasic media.
True.
What does a positive blood culture indicate?
The presence of infectious agents in the bloodstream.
What is the recommended method for collecting blood specimens for culture?
Using sterile technique with venipuncture.
Fill in the blank: Castaneda’s biphasic media is designed to enhance the growth of ______ organisms.
Fastidious.
What is the first step after obtaining a blood specimen for culture?
Inoculate the media immediately.
Multiple Choice: Which of the following is a common contaminant in blood cultures? A) Staphylococcus epidermidis B) Streptococcus pneumoniae C) Listeria monocytogenes D) Escherichia coli
A) Staphylococcus epidermidis.
What is the main advantage of using biphasic media over traditional media?
Increased sensitivity for detecting a wider range of pathogens.
True or False: Blood cultures should be performed only in cases of suspected septicemia.
False.
What is the role of glucose in BHI broth?
To serve as a carbohydrate source for microorganisms.
