Which organism is CAMP test positive, according to the material?

Which organism is CAMP test positive, according to the material?

• A. Listeria monocytogenes
• B. Streptococcus agalactiae
• C. Streptococcus pneumoniae
• D. Enterococcus faecalis

Answer: (A)

The CAMP test detects a CAMP factor produced by certain bacteria that enhances the beta-hemolysis caused by Staphylococcus aureus on blood agar. The classic positive result occurs with Streptococcus agalactiae (group B Streptococcus). When an organism suspected of being CAMP-positive is plated perpendicularly to a streak of S. aureus, the area of hemolysis enlarges into a distinctive arrowhead-shaped zone toward the S. aureus due to the interaction between the CAMP factor and beta-lysin. This pattern helps differentiate group B strep from other beta-hemolytic streptococci and from organisms that don’t produce CAMP factor. Among the options, the organism that shows this CAMP-positive reaction is group B Streptococcus. Listeria monocytogenes is not the typical CAMP-positive organism in standard testing, and Streptococcus pneumoniae and Enterococcus faecalis do not produce the CAMP factor, so they do not yield the characteristic CAMP reaction.

The CAMP test detects a CAMP factor produced by certain bacteria that enhances the beta-hemolysis caused by Staphylococcus aureus on blood agar. The classic positive result occurs with Streptococcus agalactiae (group B Streptococcus). When an organism suspected of being CAMP-positive is plated perpendicularly to a streak of S. aureus, the area of hemolysis enlarges into a distinctive arrowhead-shaped zone toward the S. aureus due to the interaction between the CAMP factor and beta-lysin. This pattern helps differentiate group B strep from other beta-hemolytic streptococci and from organisms that don’t produce CAMP factor.

Among the options, the organism that shows this CAMP-positive reaction is group B Streptococcus. Listeria monocytogenes is not the typical CAMP-positive organism in standard testing, and Streptococcus pneumoniae and Enterococcus faecalis do not produce the CAMP factor, so they do not yield the characteristic CAMP reaction.