Heat stroke is characterized by

• A. Hypothermia and no neurological symptoms
• B. Hyperthermia, AMS or neurologic deficits, and variable signs
• C. Fever with mild dehydration
• D. Normal temperature with confusion only

Answer: (B)

Heat stroke is a medical emergency caused by the body's failure to regulate its temperature, leading to dangerously high core temperatures with dysfunction of the central nervous system. The hallmark is extreme hyperthermia, typically with a core temperature above 40°C (104°F), accompanied by altered mental status or other neurologic deficits. Signs can vary widely depending on whether the exposure is exertional or classic heat stroke, and on the patient’s hydration and systemic response, so you may see confusion, agitation, seizures, or coma along with vital sign abnormalities and electrolyte disturbances.

That’s why the best description is hyperthermia with altered mental status or other neurologic symptoms and a range of additional signs. The other options don’t fit because they describe either cold conditions (hypothermia), fever from infection, or normal temperature with confusion—none of which capture the combination of extreme heat and CNS dysfunction that defines heat stroke.