Case One:
BACKGROUND
A 66-year-old male presents with subacute
confusion (encephalitis) and reports a
weight loss of 40 pounds.

His spinal fluid is abnormal and is sent to Mayo
Clinic Laboratories for an Autoimmune
Encephalopathy evaluation.

The evaluation detects an unclassified antibody, which is
reported back to the treating physician.

The patient is discovered to have a
squamous cell carcinoma of the sinus and
sees a dramatic improvement in symptoms
when treated with steroids. This antibody
was later classified as Glial Fibrillary Acidic
Protein (GFAP-IgG).

Case Two:

A 60-year-old smoker presents
to a community hospital with
subacute confusion and seizures.
The infectious disease evaluations
were negative, and the patient was
diagnosed with confusion from an
uncertain cause.

A new neurologist takes over the case and sends
an Autoimmune Encephalopathy
Evaluation on CSF to Mayo
Clinic Laboratories.

The patient is GABA-B receptor-antibodypositive, which is associated with small-cell lung cancer. The chest
CT shows a mass, and the biopsy
confirms small-cell lung cancer.
The patient improves with cancer
treatment and immunotherapy

Case Three:

A 74-year-old male presents with subacute confusion and abnormal movements. His spells are brief (2–10 seconds), affect the right side of his face and arm (occasional leg involvement), and occur up to 30x per hour. The episodes continued despite four anti-epileptic medications, and therefore, it was felt that they may be psychiatric.

An Autoimmune Epilepsy Evaluation was sent to Mayo Clinic Laboratories. The VGKC was 2.62 nmol/L (normal <=0.02), and LGI1 was positive by cell-binding assay.

The patient was diagnosed with autoimmune epilepsy associated with VGKC autoantibodies (LGI1 subtype). The episodes represented what we now term Facio-Brachial Dystontic Seizures. The confusion and seizures resolved with immunotherapy.

Raymond Rupert, patient advocate and healthcare consultant.