The latex agglutination test for Staphylococcus aureus detects which of the following?

The latex agglutination test for Staphylococcus aureus detects which of the following?

• A. Protein A
• B. Clumping Factor
• C. Protein A or Clumping Factor
• D. Coagulase

Answer: (C)

Latex agglutination identifies bacteria by using beads coated with substances that bind specific bacterial surface components. Staphylococcus aureus has two prominent surface proteins that these tests target: Protein A, which binds the Fc portion of IgG, and clumping factor (bound coagulase), which interacts with fibrinogen-coated reagents to cause clumping. If the bacteria carry either antigen, the beads cross-link and you see visible clumping, giving a positive result. This is why the test can detect Protein A or Clumping Factor. Coagulase activity itself is measured separately with a different test, not by latex agglutination.

Latex agglutination identifies bacteria by using beads coated with substances that bind specific bacterial surface components. Staphylococcus aureus has two prominent surface proteins that these tests target: Protein A, which binds the Fc portion of IgG, and clumping factor (bound coagulase), which interacts with fibrinogen-coated reagents to cause clumping. If the bacteria carry either antigen, the beads cross-link and you see visible clumping, giving a positive result. This is why the test can detect Protein A or Clumping Factor. Coagulase activity itself is measured separately with a different test, not by latex agglutination.