Parents sometimes describe a frightening experience: their child seems to change almost overnight. A child who was previously happy and functioning well suddenly develops severe anxiety, obsessive behaviours, tics, or unusual emotional outbursts. In some cases, these sudden changes may be linked to two conditions known as PANS and PANDAS.

Although these conditions are still being researched and debated within the medical community, awareness is increasing. Understanding the symptoms, possible causes, and pathways to diagnosis can help parents seek appropriate support for their child.

What are PANS and PANDAS?

PANS stands for Pediatric Acute-onset Neuropsychiatric Syndrome.
PANDAS stands for Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections.

Both conditions describe situations where a child experiences a sudden onset of neuropsychiatric symptoms, often within days. These symptoms may include obsessive-compulsive behaviours, tics, emotional dysregulation, or changes in eating and behaviour.

The key difference between them lies in the suspected trigger:

• PANS: Sudden neuropsychiatric symptoms triggered by infections, immune responses, metabolic issues, or environmental factors.
• PANDAS: A subtype of PANS specifically associated with Group A streptococcal infections (such as strep throat or scarlet fever).

Researchers believe the immune system may mistakenly attack parts of the brain during the infection response, particularly areas involved in behaviour, mood, and movement.

Key symptoms

One of the most important features of PANS and PANDAS is the sudden onset of symptoms. Unlike typical OCD or anxiety disorders, which often develop gradually, symptoms in PANS/PANDAS can appear very quickly.

Common symptoms include:

Core symptoms

• Sudden onset of obsessive-compulsive disorder (OCD)
• Sudden onset of motor or vocal tics
• Severely restricted eating or food refusal

Additional symptoms may include

• Severe anxiety or separation anxiety
• Irritability, aggression, or emotional outbursts
• Sudden decline in school performance
• Difficulty sleeping
• Changes in handwriting or motor skills
• Bedwetting or frequent urination
• Sensory sensitivities
• Hyperactivity or inattention
• Mood swings or depression

Symptoms may occur in episodes or “flares”, often linked to infections or immune triggers. Some children improve significantly between episodes.

Similarities and differences between PANS and PANDAS

Although the two conditions are closely related, there are some important distinctions.

Similarities

• Sudden onset of neuropsychiatric symptoms
• OCD or tics often present
• Symptoms may appear rapidly (sometimes within days)
• Likely involvement of the immune system
• Episodes or flares may occur

Differences

eature	PANS	PANDAS
Trigger	Various infections or immune triggers	Specifically linked to strep infection
Diagnostic criteria	Broader	Narrower
Age of onset	Typically childhood	Usually age 3 to puberty

PANDAS is therefore often considered a specific form of PANS triggered by streptococcal infections.

Diagnosis

Diagnosing PANS or PANDAS can be challenging because:

• There is no single laboratory test that confirms the diagnosis.
• Symptoms overlap with other conditions such as OCD, Tourette syndrome, ADHD, anxiety, or Autism Spectrum Disorder.

Diagnosis typically involves:

1. A detailed clinical history
2. Evaluation of symptom onset (particularly sudden onset)
3. Medical examination
4. Tests for infections, especially strep
5. Blood tests to look for immune or inflammatory markers

For PANDAS specifically, clinicians often look for evidence of a recent streptococcal infection, such as a throat swab or elevated strep antibodies.

Because many other conditions can cause similar symptoms, doctors must rule out other possible explanations before diagnosing PANS or PANDAS.

Who should parents consult?

If you suspect PANS or PANDAS, the first step is to consult your child’s paediatrician or GP.

They may refer your child to specialists such as:

• Paediatric neurologists
• Child psychiatrists
• Immunologists
• Infectious disease specialists
• Clinical psychologists or psychiatrists experienced in OCD and neurodevelopmental conditions

A multidisciplinary approach is often helpful, as these conditions sit at the intersection of neurology, immunology, and mental health.

Parents should seek urgent medical advice if symptoms appear suddenly or significantly impact a child’s daily functioning.

Treatment options

Treatment usually focuses on three main areas:

1. Treating underlying infections

If a strep infection is identified in PANDAS, doctors typically prescribe antibiotics to treat the infection.

In some cases, treating the infection may significantly improve symptoms.

2. Managing inflammation and immune responses

Some treatment plans may include:

• Anti-inflammatory medications
• Short courses of steroids
• In severe cases, intravenous immunoglobulin (IVIG) therapy

These approaches are usually considered when symptoms are severe or persistent.

3. Psychological and behavioural support

Children may also benefit from:

• Cognitive Behavioural Therapy (CBT)
• Exposure and Response Prevention (ERP) therapy
• Medication such as SSRIs for OCD or anxiety symptoms

Support at school and at home is often an important part of recovery.

Prognosis

The outlook for children with PANS or PANDAS varies widely.

Some children recover fully, especially when the underlying infection is identified and treated early. Others may experience recurring episodes or ongoing symptoms that require longer-term support.

Research into these conditions is ongoing, and there is still debate in the medical community about diagnostic criteria and treatment approaches. More large-scale studies are needed to better understand causes and optimal treatments.

A note for parents

A sudden and dramatic change in your child’s behaviour can be distressing. While PANS and PANDAS are relatively rare, they highlight the complex relationship between the immune system, infections, and the brain.

If your child experiences a rapid onset of OCD, tics, or severe behavioural changes, it is important to consult a healthcare professional for a thorough evaluation.

Early assessment and a coordinated treatment plan can make a meaningful difference for many families.

Visit https://panspandasuk.org/ for more information.

References

1. National Institute of Mental Health (NIMH). PANS and PANDAS: Questions and Answers.
2. Stanford Medicine. PANS – Pediatric Acute-onset Neuropsychiatric Syndrome.
3. Cleveland Clinic. PANDAS Syndrome: Causes, Symptoms and Treatment.
4. International OCD Foundation. Treatment for PANS and PANDAS.
5. Stanford Children’s Health. Diagnosis and Treatment for PANS and PANDAS.
6. Mindd Foundation. PANS and PANDAS.
7. Global Autoimmune Institute. PANDAS, PANS and Autoimmunity.
8. UK Parliament House of Commons Library. PANS and PANDAS research briefing.