Hyperpyrexic Toxic Shock Syndrome in Association with TSST-1 Cross-Reactive Superantigen SE-like X-Producing Staphylococcus aureus: Case Report, Toxin Analysis and a Proposed Case Definition

Herein, we report two additional cases of extreme pyrexia and rapid death due to Staphylococcus aureus infection. The organisms produced a variant superantigen, cross-reactive with toxic shock syndrome toxin-1 (TSST-1 cross-reactive superantigen SE-like X), which we purport to be the causative agent for this syndrome.