Diagnosis
Your doctor may order lab work or imaging scans to help determine what’s causing your symptoms.
Laboratory tests
Many infectious diseases have similar signs and symptoms. Samples of body fluids can sometimes reveal evidence of the particular microbe that’s causing the illness. This helps the doctor tailor treatment.
- Blood tests. A technician obtains a sample of blood by inserting a needle into a vein, usually in the 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 the throat, or other moist areas of the 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 the cerebrospinal fluid through a needle carefully inserted between the bones of the lower spine. You’ll usually be asked to lie on your side with your knees pulled up toward your chest.
