What is sepsis?

Dr. Leigh Vinocur, MD
Emergency Medicine Specialist

Sepsis is a serious multi-system potentially life-threatening complication that can occur with any infection. Once sepsis develops, it causes a series of chemicals reactions in response to, usually, a bacterial infection spreading throughout the bloodstream. This triggers a series of inflammatory reactions, which can increase both blood clotting and bleeding, then in turn damage organs and blood vessels causing multi-organ failure—eventually leading to septic shock as blood pressure drops. Once this cascade of reactions is initiated, the problem goes beyond just treating the infection. Despite antibiotics, which may kill the offending bacteria, once a person becomes severely septic, it is often too late and the end result is death.

According to the Centers for Disease Control and Prevention (CDC), sepsis is one of the top 10 causes of death in the US. Often, people can recover from early to mild sepsis, but there is a 50 percent mortality rate for those that develop late severe sepsis.

Even though most people have never heard of this condition, sepsis is the number one cause of hospital mortalities (though you can catch it anywhere). It's estimated that there are about 1 million cases of sepsis annually in North America, resulting in 300,000 deaths. Worldwide it accounts for 10 million deaths every year. Sepsis (sometimes called systemic inflammatory response syndrome, or SIRS) strikes when the immune system becomes hyper-stimulated as it fights an infection. This causes widespread inflammation that triggers formation of microscopic blood clots. This clotting can reduce blood flow and oxygen flow and cause vital organs to fail. Even though sepsis is usually a reaction to a bacterial infection, it can also be triggered by a viral, parasitic, or fungal infection.

Sepsis can occur when bacteria get into your blood and cause symptoms such a fever, chills, and confusion. Severe sepsis can even lead to poor function of your heart, liver, lungs, and kidneys. Bacteria may enter your blood from infections such as dental infections or bladder infections.

Sepsis is an immune response, normally to a bacterial infection, throughout the whole body. Your immune system responds to infection with inflammation at the site of the infection, but with sepsis your entire body becomes inflamed. Sepsis could potentially be life-threatening if antibiotics are not taken soon after the systemic response. Sepsis can result in either an unusually high or low temperature, and may lead extremely low blood pressure or septic shock.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.