Autoimmune encephalitis is a neurological condition where the immune system mistakenly attacks healthy brain tissue, causing inflammation and serious neurological symptoms. It is caused by autoantibodies such as cytosolic 5'-nucleotidase 1A (cN-1A) antibodies that target brain proteins and trigger immune-mediated damage. The Cytosolic 5'-Nucleotidase 1A Antibody (IgG) test is the most important test for diagnosis because it identifies these specific autoantibodies in the blood.
90-day money-back guarantee
Lab order in minutes
Save a trip to the doctor
Low prices since 2005
Labs within 2 miles
Autoimmune encephalitis is caused by autoantibodies that mistakenly attack proteins in the brain, leading to inflammation and neurological damage. Specific autoantibodies like cytosolic 5'-nucleotidase 1A (cN-1A) antibodies, NMDA receptor antibodies, and LGI1 antibodies are known triggers of this condition. In some cases, autoimmune encephalitis develops after a viral infection, as a paraneoplastic syndrome associated with cancer, or without any identifiable trigger. The immune system incorrectly identifies brain tissue as foreign, launching an attack that disrupts normal brain function and causes symptoms ranging from memory problems to seizures and psychiatric changes.
The Cytosolic 5'-Nucleotidase 1A (cN-1A) Antibody (IgG) test is the most important blood test for autoimmune encephalitis because it detects specific IgG antibodies that attack brain tissue. When these cN-1A antibodies are present at high levels, they confirm the autoimmune nature of the encephalitis and help guide treatment decisions. Additional antibody panels may be needed to check for other autoantibodies like NMDA receptor, LGI1, CASPR2, and GAD65 antibodies, depending on your symptoms. While blood tests are essential for identifying autoantibodies, diagnosis requires a comprehensive evaluation including cerebrospinal fluid analysis, MRI imaging, and EEG studies, all interpreted together with your clinical symptoms by a neurologist.
You should get tested if you experience sudden or rapid onset of psychiatric symptoms like confusion, hallucinations, or personality changes combined with neurological symptoms such as seizures, memory problems, or movement disorders. Testing is particularly important if you develop unexplained behavioral changes, difficulty speaking, abnormal movements, or altered consciousness that cannot be explained by other medical conditions. You should also consider testing if you have a known autoimmune condition or cancer and develop new neurological or psychiatric symptoms, as these can be early signs of autoimmune encephalitis requiring urgent medical attention.
Save a trip to the doctor, go directly to the lab
Instant orders, results often overnight*
Results explained in simple language
Reviewed by US licensed doctors
Fast & confidential, we never sell or share your data
No insurance needed, transparent pricing
What this means
Your test came back negative, meaning no cN-1A antibodies were detected in your blood. This result makes inclusion body myositis less likely, though it doesn't completely rule it out since some people with IBM test negative. If muscle weakness persists, your doctor may recommend additional tests or evaluation.
Recommended actions
Discuss your ongoing symptoms with a neurologist or rheumatologist
Consider additional muscle testing such as EMG or muscle biopsy if symptoms continue
Maintain muscle strength through gentle physical therapy and regular movement
Keep a symptom diary to track any progression or changes in weakness patterns
Not overhyped or overpriced. Just comprehensive blood testing made simple and for everyone.
3303 reviews
Sample results
Your 24/7 Personal Lab Guide
Quick questions:
