Tests and diagnosis

By Mayo Clinic Staff

Diagnosing sepsis can be difficult because its signs and symptoms can be caused by other disorders. Doctors often order a battery of tests to try to pinpoint the underlying infection.

Blood tests

A sample of your blood can be tested for:

  • Evidence of infection
  • Clotting problems
  • Abnormal liver or kidney function
  • Impaired oxygen availability
  • Electrolyte imbalances

Other laboratory tests

Depending on your symptoms, your doctor may also want to run tests on one or more of the following bodily fluids:

  • Urine. If your doctor suspects that you have a urinary tract infection, he or she may want your urine checked for signs of bacteria.
  • Wound secretions. If you have a wound that appears infected, testing a sample of the wound's secretions can help show what type of antibiotic might work best.
  • Respiratory secretions. If you are coughing up mucus (sputum), it may be tested to determine what type of germ is causing the infection.

Imaging scans

If the site of infection is not obvious, your doctor may order one or more of the following imaging tests:

  • X-ray. Using low levels of radiation, X-rays are good for visualizing problems in the lungs.
  • Computerized tomography (CT). Infections in the appendix, pancreas or bowels are easier to see on CT scans. This technology takes X-rays from a variety of angles and combines them to depict cross-sectional slices of your body's internal structures.
  • Ultrasound. This technology uses sound waves to produce real-time images on a video monitor. Ultrasound may be particularly useful to check for infections in your gallbladder or ovaries.
  • Magnetic resonance imaging (MRI). MRIs may be helpful in identifying soft tissue infections, such as abscesses within the spine. This technology uses radio waves and a strong magnet to produce cross-sectional images of your internal structures.
Jul. 23, 2014

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