(Christie, Atkins, Munch, Petersen)
Test is based on some bacteria property to produce a diffusible extracelluar protein (CAMP factor) that, together
with the beta-lysin of Staphylococcus aureus, enhances the lysis of red blood cells.
Prepare sheep blood agar as described in "Hemolysis" page.
Streak a single line of Staphylocccus aureus on a blood agar plate then
make streaks of the unknown strain (beta hemolytic streptococci)
perpendicularly but not touching the S. aureus. A 2-3 mm space should
remain between the streaks. Invert the plate and incubate it at 37°C, 24
hours. Reaction is positive if an enhanced hemolysis in the shape of an
arrowhead, at the juncture of the streaks, is observed.
Do not incubate plates under anaerobic conditions.
1. H. Raducanescu, V.Bica-Popii,1986. Bacteriologie veterinara, Ed. Ceres, Bucuresti.
2. Margaret Barnett, 1992. Microbiology Laboratory Exercises. Wm. C. Brown Publishers.
3. Murray, P.R., Baron, E. J., Jorgensen, J.J., Pfaller, M.A., and Yolken, R.H. Manual of Clinical Microbiology, 8th ed.
ASM Press: Washington, DC, 2003.
|CAMP test, lines 2 & 4 from left to right are positive
(c) Costin Stoica