Diagnostic Testing

This blog post provides guidance on diagnostic testing for autoimmune encephalitis, including answers to common questions and and additional resources for families and patients. Please be sure to review the disclaimer at bottom. If you have additional resources or are told something different, please let us know so we can provide the most up to date and accurate information possible.

Diagnostic Testing Options: Serum vs Spinal fluid

When getting tested for AE, you and your medical team will have to decide whether to use a blood test (serum) or a spinal tap (spinal fluid).  A simple blood test is generally the first option for most patients.  However a spinal tap provides a much more sensitive test and more accurate results.  Your medical team will help determine the risk / reward of each testing option.

Diagnostic Testing Options: What Tests to run?

The second question is which tests to run?  Ten years ago, there were no commercial tests for any AE antibodies. Today, up to 20 antibodies are known to cause AE with commercial tests available for many of these antibodies.

Several labs offer diagnostic tests for autoimmune disorders of the CNS, including autoimmune encephalophaty, autoimmune epilepsy and autoimmune dementia.  Other tests for inflammation and immune system activation may be ordered at the same time or when a negative AE tests comes back.  These additional tests can help determine whether an immune response might be related to a patient’s symptoms.

Diagnostic Labs:

Mayo Medical Laboratories – Mayo as created a set of lab panels to test for various types of autoimmune encephalitis.  Much more information is available on the Mayo website.

Athena Labs – Athena Labs offers several diagnostic panels based on symptoms and expected diagnosis.  Physician and patient resources are available.

Diagnostic Testing Considerations

When discussing diagnostic testing options with your medical team, consider your insurance company policy and requirements.  How your doctor codes the potential diagnosis could impact coverage of any tests as well as payment for future treatments.  You may want to explore what your insurance company covers even as you seek a diagnosis.  As an example, insurance company Aetna provides a website outlining when they will cover diagnostic tests for potential neurologic diseases.

If your test comes back negative for antibodies related to AE, your medical team should consider additional factors to make a final diagnosis.  The AE Clinicians Network provides a list of clinicians with experience diagnosis antibody-negative AE.  Consider asking your medical team to reach out to one of these experts if questions arise about how to diagnosis antibody-negative AE.


Disclaimer: This information is intended for informational and educational purposes only and in no way should be taken to be the provision or practice of medical, nursing or professional health-care advice or services.  The information should not be considered complete or exhaustive and should not be used in place of a visit, call, consultation or advice of your physician or other health-care provider.  You should not use the information in this or any Autoimmune Encephalitis Alliance, Inc. communication to diagnose or treat autoimmune encephalitis or any other disorder without first consulting with your physician or healthcare provider. Any referral to physicians is provided as a courtesy only.