Sepsis is a life-threatening medical emergency that occurs when the body’s response to an infection becomes dysregulated and begins to damage its own tissues and organs.
Normally, the immune system fights infection locally. In sepsis, that response goes systemic — flooding the entire body with inflammatory signals that can cause widespread tissue damage, organ failure, and death.
Common causes include bacterial infections (most often), as well as viral, fungal, or parasitic infections. Common sources are the lungs (pneumonia), urinary tract, abdomen, or skin.
Key signs and symptoms:
- High or abnormally low body temperature
- Rapid heart rate and breathing
- Confusion or altered mental state
- Extreme pain or discomfort
- Clammy or discolored skin
- Low blood pressure
Progression: Sepsis exists on a spectrum of severity:
- Sepsis — infection plus a dysregulated systemic response
- Severe sepsis — organ dysfunction begins (kidneys, liver, lungs, etc.)
- Septic shock — dangerously low blood pressure that doesn’t respond to fluids, carrying a mortality rate above 40%
Treatment centers on early antibiotics, IV fluids, identifying and controlling the infection source, and supportive care in an ICU setting. Time is critical — outcomes worsen significantly with each hour of delayed treatment.
Sepsis affects approximately 49 million people worldwide annually and is responsible for around 11 million deaths per year, making it one of the leading causes of hospital mortality.