Susannah Cahalan was the first case of Anti-NMDA-Receptor Autoimmune Encephalitis to be discovered at NYU and she was the 217th person ever to be diagnosed.
What is it?
Anti-NMDA- (N-methyl D-aspartate) receptor autoimmune encephalitis is an immunologically-mediated disorder, where the cells of the immune system attack NMDA receptors. NMDA receptors are highly specialized proteins located on the surface of the brain nerve cells, and are widely distributed throughout the brain, particularly in the regions that control cognition, behavior, and personality (frontal lobe), memory and mood (hippocamus), and emotions (amygdala). These receptors control “synaptic transmission”, a process by which brain nerve cells can communicate with each other. This communication among brain nerve cells is critical for normal cognition, behavior, mood and emotions.
What are the symptoms?
When these receptors are attacked by antibodies, patients will experience flu-like symptoms with some bizarre behavior and mood changes, rapidly followed by severe psychosis, paranoia and delusions of persecution, hallucinations, agitation, and emotional outbursts. As the disease progresses, neurological symptoms emerge, which include frequent seizures that are often drug-resistant, reduced level of consciousness, catatonia, fluctuation of blood pressure and heart rate/rhythm, catatonia, abnormal movements and posturing of extremities or face.
Who is at risk?
This disease affect mostly young women, many with ovarian Teratomas. Teratomas are tumors made up of different tissue types, including tissue that looks like normal brain tissue and expresses harmful NMDA receptors that are similar to normal ones in the brain. These harmful NMDA receptors within the tumor provoke the immune system to produce antibodies that do not only tackle harmful NMDA receptors within the tumor, but also the good ones in the brain, causing brain inflammation. More recently, this disease was found also in children and men.
How is it diagnosed?
Detection of these antibodies in the blood is necessary to confirm the diagnosis, which can be easily achieved by a simple, commercially available blood test, an NMDA-Receptor Antibody blood test. This disease should be considered in cases of unexplained psychiatric symptoms or unexplained encephalitis. Immune therapies are often effective in curing the disease, although the recovery is often slow. However, with delayed treatment, coma, severe permanent neurological and psychiatric complications, and even death, can occur.