Your doctor may order lab work or imaging scans to help determine what's causing your symptoms.
Many infectious diseases have similar signs and symptoms. Samples of your body fluids can sometimes reveal evidence of the particular microbe that's causing your illness. This helps your doctor tailor your treatment.
- Blood tests. A technician obtains a sample of your blood by inserting a needle into a vein, usually in your arm.
- Urine tests. This painless test requires you to urinate into a container. To avoid potential contamination of the sample, you may be instructed to cleanse your genital area with an antiseptic pad and to collect the urine midstream.
- Throat swabs. Samples from your throat, or other moist areas of your body, may be obtained with a sterile swab.
- Stool sample. You may be instructed to collect a stool sample so a lab can check the sample for parasites and other organisms.
- Spinal tap (lumbar puncture). This procedure obtains a sample of your cerebrospinal fluid through a needle carefully inserted between the bones of your lower spine. You'll usually be asked to lie on your side with your knees pulled up toward your chest.
Imaging procedures — such as X-rays, computerized tomography and magnetic resonance imaging — can help pinpoint diagnoses and rule out other conditions that may be causing your symptoms.
During a biopsy, a tiny sample of tissue is taken from an internal organ for testing. For example, a biopsy of lung tissue can be checked for a variety of fungi that can cause a type of pneumonia.
July 23, 2014
- Understanding microbes in sickness and in health. National Institute of Allergy and Infectious Diseases. http://www.niaid.nih.gov/topics/microbes/Pages/default.aspx. Accessed May 20, 2014.
- McPhee SJ, et al., eds. Pathophysiology of Disease. 6th ed. New York, N.Y.: The McGraw-Hill Companies; 2010. http://accessmedicine.mhmedical.com/content.aspx?bookid=339&Sectionid=42811304. Accessed May 20, 2014.
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- Stopping the spread of germs at home, work & school. Centers for Disease Control and Prevention. http://www.cdc.gov/flu/protect/stopgerms.htm. Accessed May 22, 2014.
- Basics for Handling Food Safely. U.S. Department of Agriculture. http://www.fsis.usda.gov/wps/portal/fsis/topics/food-safety-education/get-answers/food-safety-fact-sheets/safe-food-handling/basics-for-handling-food-safely/ct_index. Accessed May 22, 2014.
- Sexually transmitted diseases (STDs). Centers for Disease Control and Prevention. http://www.cdc.gov/std/prevention/default.htm. Accessed May 22, 2014.
- Viral meningitis. Centers for Disease Control and Prevention. http://www.cdc.gov/meningitis/viral.html#transmission. Accessed May 22, 2014.