Sepsis: Signs, Causes and Treatment

What sepsis is

Normally, the immune system fights infection locally. In sepsis, the response becomes overwhelming and uncontrolled. Inflammation, leaky blood vessels and clotting problems reduce blood flow to organs, causing them to malfunction.

Septic shock is the most severe stage: blood pressure stays dangerously low despite fluids, and medicines (vasopressors) are needed to keep blood flowing. Death rates are much higher.

Sepsis is not contagious, but the infections that cause it can be.

Causes

Any infection can lead to sepsis, but the most common sources are:

• lungs: pneumonia, flu, COVID-19
• urinary tract: urinary tract infections and kidney infections
• skin: cellulitis, wounds, burns, IV line sites
• abdomen: appendicitis, bowel perforation, gallbladder infection
• brain: meningitis
• bloodstream: from catheters or injections

Bacteria cause most cases, including Staphylococcus aureus, E. coli and Streptococcus. Viruses and fungi can also cause sepsis.

Who is at highest risk

• adults 65 or older
• babies under 1 year, especially newborns (neonatal sepsis)
• people with diabetes, chronic lung, kidney or liver disease, or cancer
• weakened immune systems: chemotherapy, transplants, HIV, steroids
• recent surgery, hospitalization, catheters or breathing tubes
• pregnancy and the weeks after birth or miscarriage
• previous sepsis

Signs and symptoms

The Sepsis Alliance TIME acronym:

• Temperature: higher or lower than normal
• Infection: signs of one
• Mental decline: confused, sleepy, hard to wake
• Extremely ill: severe pain, discomfort, shortness of breath, "I feel like I might die"

Other signs:

• fast heart rate and fast breathing
• shivering, chills or feeling very cold
• clammy, pale, blotchy or mottled skin
• little or no urine
• low blood pressure, dizziness or fainting

In older adults

Sepsis may cause no fever. New confusion, falls, weakness or simply "not being themselves" can be the main signs.

In babies and children

• fast breathing, grunting or pauses in breathing
• fever or low temperature
• poor feeding, no wet diapers for 12 hours
• floppy, very sleepy or unusually irritable
• cold hands and feet, mottled or bluish skin
• a rash that does not fade with pressure

Diagnosis

Doctors screen for sepsis using vital signs (temperature, heart rate, breathing rate, blood pressure, oxygen, mental status) and tests:

• blood tests: white cell count, lactate (a marker of poor blood flow), kidney and liver function, clotting, blood cultures
• urine tests and cultures
• chest X-ray, ultrasound or CT to find the source
• SOFA score to measure organ dysfunction

Treatment starts before all results return.

Treatment

Speed saves lives. Guidelines recommend, ideally within the first hour:

• broad-spectrum IV antibiotics, later narrowed based on culture results
• IV fluids to restore blood pressure
• oxygen and breathing support
• source control: draining abscesses, removing infected lines, surgery for perforations or dead tissue
• vasopressors for septic shock
• intensive care for organ support: ventilator, dialysis
• steroids in some patients with septic shock

Recovery and post-sepsis syndrome

Many people recover fully, but up to half of survivors have lasting effects, called post-sepsis syndrome:

• fatigue and weakness
• trouble sleeping
• memory and concentration problems
• anxiety, depression and PTSD
• hair loss and muscle and joint pain
• reduced organ function
• higher risk of another infection or sepsis

Rehabilitation, follow-up care and support groups help. Some survivors lose limbs if blood flow was severely reduced.

Outlook

Sepsis kills about 350,000 adults in US hospitals each year, according to CDC estimates. Risk of death rises with every hour treatment is delayed and is highest in septic shock. Early recognition is the single most important factor in survival.

Prevention

• vaccines: flu, COVID-19, pneumococcal, RSV for eligible adults, and routine childhood vaccines
• treat infections promptly and finish prescribed antibiotics
• wash hands and keep wounds clean
• manage chronic conditions such as diabetes
• know the signs, and ask "could this be sepsis?" if an infection is getting worse

Frequently asked questions

What are the early signs of sepsis?

Early signs include fever or a low temperature with shivering, a fast heart rate, fast breathing, confusion or unusual sleepiness, severe pain or discomfort, and clammy or mottled skin. In older adults, new confusion may be the main sign.

What causes sepsis?

Sepsis is caused by the body's extreme response to an infection, most often pneumonia, urinary tract infections, skin infections or abdominal infections. Bacteria are the most common cause, but viruses and fungi can also trigger it.

How fast does sepsis progress?

Sepsis can worsen within hours, especially in babies, older adults and people with weak immune systems. Each hour of delay in antibiotics increases the risk of death in septic shock, so prompt emergency care is critical.

Can you survive sepsis?

Yes. Most people survive, especially with early treatment. Survival is lower in septic shock and in older or frail people. Many survivors have lasting effects such as fatigue, memory problems or anxiety, which improve with rehabilitation.

What is the difference between sepsis and septic shock?

Sepsis is organ dysfunction from the body's response to infection. Septic shock is the most severe form, where blood pressure stays dangerously low despite fluids and requires medicines to maintain it. It carries a much higher risk of death.