Understanding Pans: Triggers And Mechanisms Behind The Disorder

PANS (Pediatric Acute-onset Neuropsychiatric Syndrome) is a clinically defined disorder characterized by the sudden onset of obsessive-compulsive symptoms (OCD) or eating restrictions, along with acute behavioural deterioration in at least two designated domains. PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections) is a subset of PANS, with similar symptoms but triggered specifically by a streptococcal infection. The cause of PANS is unknown in most cases but is thought to be triggered by infections, metabolic disturbances, and other inflammatory reactions. Experts believe that PANS and PANDAS are caused by a problem with the immune system's response to an infection. Instead of attacking the germs, the immune system targets the basal ganglia part of the brain by mistake, leading to symptoms such as obsessions, compulsions, tics, anxiety, depression, and more.

Immune system targets the basal ganglia by mistake

PANS (Paediatric Acute-onset Neuropsychiatric Syndrome) and PANDAS (Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections) are conditions that affect the brain. They are characterised by a variety of symptoms, including mental health issues, behavioural changes and difficulties with movement. PANDAS is a subset of PANS.

PANS and PANDAS are caused by an abnormal immune and/or inflammatory response to infection. Instead of attacking the germs, the immune system targets a part of the brain called the basal ganglia by mistake. This irritation in the basal ganglia leads to the symptoms of PANS and PANDAS.

In the case of PANDAS, the abnormal immune response is triggered by a Group A Streptococcal (GAS) infection. PANDAS patients test positive for a recent streptococcal infection, such as strep throat, perianal strep or scarlet fever.

PANS is triggered by a misdirected immune response to a variety of infections, including Lyme disease, the flu, mononucleosis, and mycoplasma bacteria. Recent research also suggests that COVID-19 infection can act as a trigger for PANS.

Both PANS and PANDAS can cause a sudden, dramatic change in personality, displayed as obsessive-compulsive disorder (OCD), anxiety, tics or other abnormal movements, personality changes, a decline in math and handwriting abilities, sensory sensitivities, restrictive eating and more.

Intense anxiety

The intense anxiety seen in PANS can manifest as heightened anxiety, separation anxiety, irrational fears, and panic episodes. This anxiety can be so strong that it may be difficult to comfort the child. In addition to anxiety, children with PANS may also experience other psychiatric symptoms such as emotional lability, depression, irritability, and aggression.

The cause of PANS is unknown in most cases, but it is thought to be triggered by infections, metabolic disturbances, and other inflammatory reactions. Specifically, PANS has been linked to infections such as Lyme disease, influenza, mononucleosis, mycoplasma, and more recently, COVID-19.

The intense anxiety and other symptoms of PANS can be treated with medicines and therapy. Doctors may prescribe antibiotics to treat the underlying infection, and cognitive behavioural therapy (CBT) can be useful in addressing the OCD and anxiety symptoms. It is important to start treatment as soon as possible, as early intervention can reduce the duration and intensity of a patient's symptoms.

Eating restrictions

PANS (Paediatric Acute-onset Neuropsychiatric Syndrome) is a clinically defined disorder characterised by the sudden onset of obsessive-compulsive symptoms (OCD) or eating restrictions, along with acute behavioural deterioration in at least two designated domains. Eating restrictions are one of the major symptoms of PANS, and a person only needs to develop one of the major symptoms (the other being OCD) to be diagnosed with PANS, in addition to two other symptoms from the PANS/PANDAS symptom list. Eating restrictions related to PANS may be caused by acute fears of contamination, choking, or vomiting. This can develop into anorexia, necessitating hospitalisation and the use of a feeding tube.

PANDAS (Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections) is a subset of PANS. Eating restrictions are not one of the five distinct criteria for diagnosis, but they are a common symptom. Eating restrictions related to PANDAS may be caused by obsessional fears of choking or contamination, or new obsessions with body image or weight.

Both PANS and PANDAS are increasingly recognised as a form of autoimmune encephalitis (AE), specifically post-infectious basal ganglia encephalitis (BGE). In both conditions, brain inflammation occurs when the body's immune system mistakenly attacks healthy brain cells, leading to autoimmune processes that affect central nervous system function.

Infections, metabolic disturbances, and inflammatory reactions

PANS (Paediatric Acute-onset Neuropsychiatric Syndrome) is a clinical diagnosis with no specific test to prove or disprove the condition. It is believed to be triggered by infections, metabolic disturbances, and inflammatory reactions.

Infections that can trigger PANS include the flu, chickenpox, mycoplasma, and Lyme disease. PANS can also be triggered by simultaneous exposure to multiple infectious organisms, which can override the natural immunological mechanisms that prevent the immune system from attacking antigens.

In the case of PANS, the immune system attacks the basal ganglia, a part of the brain that affects thoughts, feelings, movement, and other behaviours. Experts believe irritation in this part of the brain leads to the symptoms of PANS, which include severe obsessions and compulsions, new and intense fears, tics or jerky movements, anxiety, depression, aggressive behaviour, deterioration of motor skills, sensitivity to light, sound, and touch, sleep disturbances, and bedwetting.

PANDAS (Paediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections) is a subset of PANS. PANDAS is triggered specifically by a streptococcal infection, commonly known as 'strep'. This can include strep throat, perianal strep, or scarlet fever. PANDAS patients experience similar symptoms to PANS patients, including OCD or tics, uncontrollable emotions, irritability, anxiety, and loss of academic ability and handwriting skills.

Autoimmune encephalitis

The early stages of AE vary from person to person. Some people rapidly develop new or changing symptoms, such as hallucinations followed by seizures or memory problems. Symptoms may also fluctuate between improving and worsening. During this stage, people with AE are often misdiagnosed with more common conditions. Many people require numerous visits to different healthcare providers as symptoms worsen or new symptoms develop before AE is considered.

Common symptoms of AE include impaired memory and understanding, unusual and involuntary movements, involuntary movements of the face (facial dyskinesia), difficulty with balance, speech or vision, weakness or numbness, severe anxiety or panic attacks, compulsive behaviours, altered sexual behaviours, and behavioural changes such as agitation, fear or euphoria.

The treatment for AE includes surgery to remove a teratoma, steroids to reduce brain inflammation, plasma exchange to remove harmful antibodies, intravenous immunoglobulin (IVIG) to introduce antibodies from healthy donors, and immunosuppressant medications if other treatments are ineffective. Early treatment can greatly reduce symptoms and the chances of long-term complications.

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