Flying h4x0r
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Random questions on hemolysis:
Which organsims produce beta hemolysis, what enzymes are involved?
Which organisms produce alpha hemolysis, and how do you differentiate them, on culture?
Which organism produces a double layer of hemolysis, what enzymes are involved?
Which organism produces a zone of hemolysis only when cultured with beta hemolytic strep?
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| vallia
Forum Guru
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beta hemolysis
Staph aureus( alpha hemolysin)
Group A (strep pyogenes), streptolysin O, bacitracin sensitive
Group B(strep agalactiae), bacitracin resistant; CAMP positive
Group D( strep faecalis,bovis..) usually gamma
Alpha hemolysis-diferentiate by sensitivity test to bile and Optochin
Strep pneumoniae-optochin sensitive,
Strep viridans-optochin resistant
Clostridium perfringens produces double layer of hemolysis due to lecithinase: alpha toxin lyses RBC
Also produces hemolysis: haemophylus haemolyticus,Vibrio cholerae (El Tor), Listeria, Pseudomonas, Erysipelothrix(alpha), Francisella tularensis(alpha)
correct me if it's wrong and please give a classification of group D strep.
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| bactitech
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Group D CAN be hemolytic. I have seen a few that look remarkably like Group B. However, when tested with Group B latex they don't agglutinate. A quick PYR test can confirm (enterococci are PYR positive). One can also perform a Group D latex if you have the kit. Strep. faecalis is now known as Enterococcus faecalis (PYR +, bile esculin +, 6.5% NaCl +). Strep. bovis is PYR - bile esculin +, 6.5% NaCl -. Most labs use the quick PYR test as the first line of identification on gamma streptococci. Enterococcus faecalis and Enterococcus faecium are also the only two that can officially be VRE's (vancomycin resistant enterococci, usually with MIC's to vanco of >256). There are other enterococci that are not included in this category (E. avium, E. gallinarum are the most common). They can be intermediately sensitive to vanco, or even resistant, but their MIC's aren't as high and are not considered official VRE's by the powers-that-be.
Some strains of E. coli can be hemolytic, as can some Morganella morganii's (although not real strong). I have also seen hemolytic diphtheroids (Arcanobacteria I think). Then there are hemolytic Acinetobacter lwoffi's. ........
I'm sure there are others - can't think of any more right now - too late 
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Clinical Microbiology since 1974
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| Flying h4x0r
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very good!
now, can anyone answer the last question? 
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| sobia naeem
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the last answer is hemophilus influenzae.(.the satellite phenomenon)
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| bactitech
Forum Elite
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Satelliting of H. influenzae occurs when it is streaked on a blood agar plate, and a line of Staph. aureus (not a beta strep) is streaked across it. H. influenzae is not beta hemolytic.
http://www.jlindquist.net/generalmicro/dfhemo.htm... (pics here)
http://tinyurl.com/a7jq8
http://web.indstate.edu/thcme/micro/strp_lab.html
http://www.cdc.gov/groupbstrep/gbs/lab_pers_photo... (pics here)
Are you referring to the CAMP test? I've never used this in clinical practice, but I know that many labs do. We use latex because it's billable  and is able to be performed immediately. The other tests are only presumptive and require overnight incubation.
https://w ww1.fishersci.com/Coupon?gid=2775146&am...
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