Knowing that certain fastidious bacteria (e.g.Neisseria & Haemophilus species) grow on chocolate agar rather than blood agar. Wondering if all blood borne bacteria grow on chocolate agar?
I' ll answer regarding my specialty only. Brucella as a blood borne bacteria during bacteremia (fever) and as a fastidious slow growing microorganism does grow on chocolate, blood, and Brucella agar.
Hi Heng
Most blood borne pathogens will grow since chocolate agar is a "super" rich media for growth, and any bacteria that can't do haemolysis will grown in this media (and not grown in blood agar). But some bacteria may be present in the blood and not grow like specific parasitic bacteria, as Mycoplasma sp..
If you're planning some experiment with blood borne bacteria, you'll need first to evaluate their metabolic capacities/necessities, and then use the best media for growth.
Of course some of blood -borne bacteria can grow on blood ,chocolate agar plates and any other rich media required for aerobic and anaerobic techniques in case of PUO infectious diseases.
You need to understand first what is chocolate agar, it is actually heated or lysed blood agar which cause the release of factors X (heme) and V (NADPH) in the medium after the RBC lysis upon heating. So bacteria which need either factor X or factor V or even both (X+V) for their growth (as H. influenzae) will grow on it. So basically chocolate agar is more enriched than the plain blood agar and mainly the fastidious bacteria (having tough nutritional requirements) will grow at chocolate agar with more ease than on blood agar as their nutritional requirements available in free form at chocolate agar.....ready to use. So any bacterium who need such growth requirements which are provided by the chocolate agar will not hesitate to grow at all..whether blood borne or not....
Most of the bacteria grow on Chocolate agar, you need to think what type of bacteria you are suspecting from blood culture? I would do, grow initially blood culture on Selenite F broth and BHI broth. After overnight incubation, streak this broth culture on SS agar, for Salmonella isolation, BA or Chocolate agar for fastidious organisms and also can do all sort of selective medium. At the same time think about anaerobic Bacteroides sp some times cause bacteremia, you might need Thioglycolate broth.
For lab routine, we subculture the hemoculture media (broth or biphasic) on Chocolater agar. Ever.....
The chocolate agar is a complete media rich in nutrients for growth and any bacteria will grow.
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