Tests and diagnosis
By Mayo Clinic staffDiagnosing 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 a good tool to visualize problems in the lungs. X-rays are painless and take only a few minutes to complete.
- 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. The test is painless and usually takes less than 20 minutes.
- 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.
- Sepsis fact sheet. National Institute of General Medical Sciences. http://www.nigms.nih.gov/Publications/factsheet_sepsis.htm. Accessed May 16, 2011.
- Shapiro NI, et al. Sepsis syndromes. In: Marx JA, et al. Rosen's Emergency Medicine: Concepts and Clinical Practice. 7th ed. Philadelphia, Pa.: Mosby Elsevier; 2010. http://www.mdconsult.com/books/about.do?about=true&eid=4-u1.0-B978-0-323-05472-0..X0001-1--TOP&isbn=978-0-323-05472-0&uniqId=230100505-57. Accessed May 17, 2011.
- Neviere R. Sepsis and the systemic inflammatory response syndrome: Definitions, epidemiology and prognosis. http://uptodate.com/home/index.html. Accessed May 17, 2011.
- Russell JA. Shock syndromes related to sepsis. In: Goldman L, et al. Cecil Medicine. 23rd ed. Philadelphia, Pa.: Saunders Elsevier; 2008. http://www.mdconsult.com/das/book/body/191371208-2/0/1492/0.html#. Accessed May 17, 2011.
- Chang HJ, et al. Patient page: Sepsis. Journal of the American Medical Association. 2010;304:1856.

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