1. The Xpert EV Test
Your doctor can use a rapid test approved by the Food and Drug Administration (FDA) in 2007 that can diagnose a case of viral meningitis just a few hours after infection. Known as the Xpert EV test, the procedure is used in combination with other methods to rule out bacterial causes of infection, helping your doctor prescribe the correct treatment.
The Xpert EV test looks for evidence of viral meningitis in your cerebrospinal fluid. This procedure is specifically designed to detect the RNA of the enterovirus that causes meningitis. Your doctor can access results within hours. This is vital, as every minute counts when it comes to treating this potentially serious infection.
2. Spinal Taps Rule out Bacterial Causes
If the Xpert EV test is unavailable, your doctor may opt to use a lumbar puncture (also known as a spinal tap) to diagnose your symptoms. This procedure, like the rapid test, analyzes the contents of your cerebrospinal fluid. Your doctor and the lab technicians will be looking for evidence of bacterial meningitis. Lack of this evidence indicates a viral cause. Bacterial meningitis is considered the more serious of the two variants, but viral infections account for approximately 85 to 90 percent of cases.
3. Use the Meningococcal Rash Pressure Test
If a skin rash is among your symptoms, your doctor may use a meningococcal rash pressure test to determine whether viral or bacterial microbes are the source of your illness. Rashes caused by bacterial meningitis will not whiten under pressure. Your doctor will use medical instruments to apply pressure to the skin around your rash and then observe its color properties. If the rash whitens, your doctor will suspect a viral cause. He will likely use lab analyses of your cerebrospinal fluid or blood to confirm the diagnosis.
4. Blood Culture Tests
You can also diagnose viral meningitis using differential diagnostic blood tests. Your doctor will send a sample of your blood for lab analysis, where technicians will search for evidence of the presence of meningococcal bacteria. If they aren't there, your meningitis will be considered viral, and you'll be administered supportive-care treatments until the virus runs its course.
