Sepsis (Blood Infection) and Septic Shock

Sepsis is a serious medical condition caused by an overwhelming immune response to infection. Chemicals released into the blood to fight infection trigger widespread inflammation.

Inflammation may result in organ damage. Blood clotting during sepsis reduces blood flow to limbs and internal organs, depriving them of nutrients and oxygen. In severe cases, one or more organs fail. In the worst cases, infection leads to a life-threatening drop in blood pressure, called septic shock. This can quickly lead to the failure of several organs -- lungs, kidneys, and liver -- causing death.

Severe sepsis affects more than a million Americans each year. Up to half of these people will die from this condition.

The term sepsis is often used interchangeably with septicemia, a serious, life-threatening infection that gets worse very quickly and is often fatal.

Sepsis Causes and Risk Factors

Bacterial infections are the most common cause of sepsis. However, sepsis can also be caused by other infections. The infection can begin anywhere bacteria or other infectious agents can enter the body. It can result from something as seemingly harmless as a scraped knee or nicked cuticle or from a more serious medical problem such as appendicitis, pneumonia, meningitis, or a urinary tract infection.

Sepsis may accompany infection of the bone, called osteomyelitis. In hospitalized patients, common sites of initial infection include IV lines, surgical incisions, urinary catheters, and bed sores.

Although anyone can get sepsis, certain groups of people are at greater risk. They include:

  • People whose immune systems are not functioning well due to illnesses such as HIV/AIDS or cancer or use of drugs that suppress the immune system, such as steroids and those used to prevent rejection of transplanted organs
  • Very young babies
  • The elderly, particularly if they have other health problems
  • People who have recently been hospitalized and/or had invasive medical procedures
  • People with diabetes

Sepsis Symptoms

Because sepsis can begin in different parts of the body, it can have many different symptoms. Rapid breathing and a change in mental status, such as reduced alertness or confusion, may be the first signs that sepsis is starting. Other common symptoms include:


Sepsis Treatment

The first step to successful treatment for sepsis is quick diagnosis. If sepsis is suspected, the doctor will perform an exam and run tests to look for:

  • Bacteria in the blood or other body fluids
  • Source of the infection, using imaging technology such as X-ray, CT scan, or ultrasound
  • A high or low white blood cell count
  • A low platelet count
  • Low blood pressure
  • Too much acid in the blood (acidosis)
  • Altered kidney or liver function

Other tests of bodily fluids and radiologic tests, such as X-ray or CT scan, can often help in diagnosing the cause of the infection. People diagnosed with severe sepsis are usually placed in the intensive care unit (ICU), where doctors try to stop the infection, keep vital organs functioning, and regulate blood pressure.

Sepsis treatment usually begins with:

  • Broad-spectrum antibiotics, which kill many types of bacteria
  • IV fluids to maintain blood pressure
  • Oxygen to maintain normal blood oxygen

Once the infectious agent is identified, the doctor can switch to a drug that targets that particular agent. Depending on the severity and effects of sepsis, other types of treatment, such as a breathing machine or kidney dialysis, may be needed. Sometimes surgery is necessary to drain or clean an infection.

Often doctors prescribe other treatments, including vasopressors (drugs that cause the blood vessels to narrow) to improve blood pressure.

Permanent organ damage can occur in people who survive sepsis. Between 28& and 50% of patients with severe sepsis die from the infection.

WebMD Medical Reference Reviewed by Melinda Ratini, DO, MS on January 21, 2015



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NYU Langone Medical Center: "Blood Poisoning."

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National Institute of General Medical Sciences: "Sepsis Fact Sheet."

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