Explain why a staphylococcal infection might produce a medical emergency

Question

What will be an ideal response?

Answer 1

Some staphylococci produce toxins that act as superantigens, for example the staphylococcal enterotoxins and toxic shock syndrome toxin-1 (TSST-1). Superantigens can bind simultaneously to MHC class II molecules and to T-cell receptors that possess certain types of Vβ region, resulting in the activation of all T cells carrying such a receptor. Superantigens thus nonspecifically activate a large proportion of the CD4 T-cell repertoire, resulting in the production of large quantities of cytokines from the activated T cells and from macrophages activated by these cells. The systemic production of cytokines (for example TNF-α) causes increased vascular permeability and vasodilation throughout the body, leading to loss of fluid into the tissues, rapid collapse of the circulatory system (systemic shock), and organ failure. Toxic shock therefore requires immediate medical attention, primarily to replace the intravascular fluid.