Which statement best defines SIRS?

• A. Localized inflammation confined to the infection site.
• B. SIRS is a widespread inflammation, including fever (or hypothermia), tachycardia, tachypnea, leukocytosis or leukopenia.
• C. Sepsis is defined by infection with hypotension alone.
• D. Organ dysfunction is required for the diagnosis of SIRS.

Answer: (B)

SIRS is a systemic inflammatory response, not limited to a single location. It shows up as a widespread set of signs indicating the body's global reaction, typically including fever or an abnormally low temperature, a fast heart rate, rapid breathing, and an abnormal white blood cell count (either leukocytosis or leukopenia). This combination reflects the body’s nonspecific, body-wide response to a variety of insults, including infection, trauma, or pancreatitis. That’s why the statement describing a widespread inflammatory process with fever (or hypothermia), tachycardia, tachypnea, and leukocytosis or leukopenia best defines SIRS. By contrast, inflammation confined to the infection site isn’t SIRS; sepsis requires infection plus a systemic response, not hypotension alone; and organ dysfunction marks progression beyond SIRS to more severe states.