Question:

What is Autoimmune Psychosis? 

Answer:

Autoimmune Encephalitis is a neuropsychiatric disease. It is a medical illness (antibodies attacking the brain) affecting a person mind and behaviors.

Psychosis is a mental health problem signified by ‘hallucinations’ and ‘delusions’. Hallucinations occur when we experience things that aren’t really there – whether through sound, taste or sight. Delusions have more to do with how we think – we can become suspicious, irrational and have racing thoughts. Changes in mood and personality, odd or violent behavior can also be part of a psychotic episode. The causes of psychosis are varied. Drug and alcohol abuse can affect the brain and lead to psychotic behavior. People with psychosis may also have diagnoses of schizophrenia or bipolar disorder. Occasionally the cause is our own body attacking the brain. Special Y shaped molecules called antibodies that normally protect us can become confused and attack healthy parts of the body. Therefore, it is called ’antibody mediated psychosis’. This is an ’autoimmune’ disease as the body’s own immune system turns on itself.

Symptoms of antibody-mediated Psychosis

The type of antibody mediated psychosis depends on the type of antibody causing the disease. Each type has its own unique set of symptoms, but most follow a similar pattern. Quite often we experience flu-like symptoms first. Headaches, tiredness, fever etc. This could be several weeks before the mental health symptoms begin to surface, such as psychosis. At this stage, psychiatrists become involved, and you may be kept on a ward or put on certain types of drugs, often antipsychotics. As the disease progresses, more physical symptoms can follow. These include seizures or fits, abnormal movements (particularly twitches in the face), extreme tiredness or vacantness. The antibodies also attack parts of the brain linked to memory and reasoning skills. This can lead to long- and short-term memory problems, poor concentration, motivation and sequencing when trying to do daily tasks like shopping and washing.

In some people, the illness progresses to involve different parts of the brain – ‘encephalitis’ which can lead to an unresponsive coma-like state. At this stage, it becomes clear something very serious and not necessarily psychiatric is going on. The body may attack part of the brain that controls breathing, leading it to fail, so many patients end up in the intensive care unit (ICU) in hospital.

Diagnosis of antibody-mediated Psychosis

The order and intensity of the symptoms differ from disorder to disorder and patient to patient. Therefore, it can be difficult at first to diagnose what is going on. Some patients only display the psychiatric signs of psychosis with problems sleeping and with their memory. These patients are often misdiagnosed with schizophrenia, depression or bipolar disorder. In some, but not all cases, a small tumor is the cause of the body’s autoimmune response. A common example is a as a teratoma. This can occur in 58% of cases with the most common type of antibody seen, anti-NMDAr. Several of the antibodies associated with autoimmune psychosis may also have an associated tumor.  In the example of anti-NMDAr, teratoma tumor, a word for ‘little monster’, is found in the reproductive organs. These usually non-cancerous tumors contain human tissue – hair, skin, sometimes eyes and teeth! – but also, more importantly, brain tissue. It is thought that the body tries to fight off this little monster but, in the attempt, confuses the body’s own brain tissue with that of the teratoma.

When antibody mediated psychosis is suspected, diagnosis is fairly straightforward. A blood test to check for which antibodies are causing the disease is vital. A lumbar puncture (in which a tiny sample of fluid that surrounds the brain and spinal cord is collected and tested for antibodies), an EEG to look at the electrical signals in the brain and scans of the brain and body (CT and MRI) to check for tumors may also be required.

It is important to catch the disease in its early stages. This is why people who experience an out of the blue psychotic episode for the first time should be tested for antibodies. This is really key work.

Treatment

Antibody Mediated Psychosis can be treated with Immunotherapy, the goal is to prevent the antibodies from attacking the brain.

Immunotherapy treatment is the combination of treatments that include first-line therapies: steroids, IVIG, plasma exchange (plasmapheresis) and second -line therapies: Rituxamab (Rituxan) and cyclophosphamide (Cytoxan), followed in many cases by steroid-sparing agents such as Cellcept or Azathioprine in the long-term. The fact that patients who receive second line immunotherapies have fewer relapses, is leading many physicians to use rituximab initially as a first line treatment.

The After-effects of Psychosis?

Experiencing a psychotic episode, whether your own or someone else’s can be incredibly devastating. Even if the episode itself is short-lived, there can still be a long road to recovery and acceptance. Treatment depends on the progress of the psychosis and how ready you are to deal with it. Early Intervention Team including cognitive behavioral therapy. Even with a neurological diagnosis such as antibody mediated psychosis, some mental health therapies and treatments may also be introduced to help manage symptoms and repair the emotional damage psychosis can cause.

REFERENCES:  Antibody Mediated Psychosis SINAPP 2016 Pamphlet