PANDAS and PANS: The Overlooked Link Between Infection, Immunity, and Behaviour

Awareness Week Feature

Across countless families, the same story repeats itself. A child once thriving begins to change – anxiety creeps in, rituals emerge, tics appear, and eating becomes restricted. The changes may come after a throat infection, a viral illness, mould exposure, or even a physical or emotional trauma. Sometimes the shift is sudden, but often it unfolds quietly over weeks or months until the child’s behaviour is unrecognisable.

For many, this marks the beginning of PANDAS or PANS – conditions still too often misunderstood, dismissed, or misdiagnosed.

What Are PANDAS and PANS?

PANDAS (Paediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal infection) and PANS (Paediatric Acute-onset Neuropsychiatric Syndrome) describe immune-mediated conditions in which the body’s defence system begins to affect the brain.

In PANDAS, the initial trigger is usually a Group A Streptococcal infection such as strep throat or scarlet fever. In PANS, the triggers can vary: viral infections like Epstein-Barr or HHV-6, bacterial infections such as Mycoplasma or Lyme, exposure to mould, coeliac disease, gluten sensitivity, or even physical or emotional trauma.

While diagnostic criteria have historically focused on “abrupt onset”, clinical reality is broader. Many children develop symptoms progressively – a slow drift from mild anxiety, sleep disturbance, or irritability into more severe obsessive, restrictive, or neuropsychiatric behaviours. The key feature is the pattern of immune involvement, not the speed of change.

Moving Beyond the Old Explanations

For decades, the prevailing theory has been molecular mimicry – that microbes resemble human tissue closely enough to confuse the immune system, causing it to attack both.

Recent research challenges this view. A landmark study from the Garvan Institute in Australia found that infections may not “trick” the immune system at all. Instead, they can push it into chronic overdrive, generating rogue B cells that continue to attack long after the infection has cleared.

This finding, although based on hepatitis C-related vasculitis, provides a compelling framework for understanding PANDAS and PANS. It suggests these may not be classic autoimmune diseases but conditions of immune dysregulation – where the immune system has lost the ability to regulate itself and remains locked in attack mode.

This could explain why many children relapse even after the infection is treated and why therapies that restore immune balance, rather than simply eradicating microbes, are often the most effective.

The Brain – Immune Connection

Research from Dr Dritan Agalliu and his team at Columbia University has shown how repeated immune activation can weaken the blood-brain barrier (BBB) – the crucial filter protecting the brain from immune cells and inflammatory molecules.

When this barrier becomes compromised, immune factors can enter the brain, activating microglia and disrupting neurotransmission. This can result in the obsessive-compulsive symptoms, anxiety, tics, irritability, and cognitive changes seen in both PANDAS and PANS.

In some children, both mechanisms may be at play – chronic immune activation producing rogue cells, and a weakened BBB allowing those cells and antibodies to reach the brain. The outcome is the same: neuroinflammation driving behavioural and neurological symptoms.

Why Some Children Develop PANDAS or PANS

Not every child exposed to strep or viral infections will develop PANDAS or PANS. The difference lies in susceptibility – a combination of genetic, environmental, and immune factors that determine how a child responds to immune stress.

Common background patterns include:
– Family history of autoimmunity, allergies, or chronic fatigue
– Early antibiotic exposure or caesarean birth affecting gut microbiome development
– Chronic gut inflammation or dysbiosis
– Ongoing mould or toxin exposure
– Nutrient imbalances affecting immune regulation

For these children, a new infection or trauma can be the final insult that tips an already overactivated system into dysfunction.

Testing: Looking for Immune Clues

Diagnosis remains clinical – based on history, symptom pattern, and response to treatment – but targeted testing helps define the full picture.

We typically investigate:
– Strep antibody titres (anti-streptolysin O and anti-DNase B)
– Viral panels for Epstein-Barr, HHV-6, CMV, Mycoplasma, and Lyme
– Immune profiling, including IgG subclasses, complement, ANA, and MBL
– Thyroid and autoimmune screening
– Markers of chronic inflammation and detoxification efficiency
– Mycotoxin testing when mould exposure is likely

No single test confirms PANDAS or PANS. It is the pattern – a dysregulated immune system, repeated infections, systemic inflammation, and neuropsychiatric symptoms – that defines these conditions.

Treatment: Calming and Rebuilding the Immune System

Conventional care in the UK often relies on antibiotics, anti-inflammatories, or occasionally IVIG (intravenous immunoglobulin). These can help, but infection control alone is rarely sufficient.

Antibiotics such as macrolides and tetracyclines provide partial benefit not only through antimicrobial activity but through immune-modulating effects, reducing cytokine activity and neuroinflammation. Yet when the immune system is trapped in chronic overactivation, suppression is temporary relief, not repair.

Our clinical approach is to identify and address every underlying driver: chronic infections, nutrient deficiencies, histamine and methylation issues, gut dysbiosis, mould, and toxic load. We aim to restore immune tolerance and re-establish regulation.

One of the most promising interventions in our clinical experience is Microimmunotherapy (MIT). MIT uses ultra-low doses of immune messengers to gently retrain the immune system. Unlike steroids or immunosuppressants, MIT seeks not to silence but to recalibrate – restoring immune precision and stability.

We have seen children stabilise, relapse less often, and regain emotional and cognitive function once immune regulation is restored. While further studies are needed, MIT represents a promising shift in the treatment of chronic immune dysregulation.

Rethinking the Core Problem

PANDAS and PANS are not simply infections gone wrong. They are the consequence of an immune system unable to return to balance. Whether triggered by bacteria, viruses, toxins, or trauma, the result is the same: ongoing neuroinflammation disrupting behaviour, mood, and cognition.

This explains why approaches targeting immune repair – from Microimmunotherapy to mitochondrial and gut support – are proving transformative where antibiotics alone fail.

The Way Forward

Awareness remains the greatest barrier. Too many families are told their child’s behaviour is psychological, defiant, or “just autism”. Early recognition changes outcomes. When clinicians look beyond the surface and consider immune, metabolic, and infectious history, the pattern becomes obvious – and treatable.

With growing research, evolving immune-modulating therapies, and clinical collaboration, the outlook for children with PANDAS and PANS is improving. What is needed now is education, early action, and a clear message: these are treatable immune disorders, not lifelong behavioural diagnoses.

IMPORTANT

The information provided in this article is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always consult qualified medical or functional medicine practitioners familiar with your child’s health history before introducing any treatment or supplement.

Concerned about your child’s health? We’d love to talk.

References

Susan E Swedo, Jennifer Frankovich, Tanya K Murphy: ‘Overview of Treatment of Pediatric Acute-Onset Neuropsychiatric Syndrome’. Journal of Child and Adolescent Psychopharmacology. www.liebertpub.com/doi/full/10.1089/cap.2017.0042

Kiki Chang, Harold S Koplewicz, Ron Steingard: ‘Special Issue on Pediatric Acute-Onset Neuropsychiatric Syndrome’. Journal of Child and Adolescent Psychopharmacology. www.liebertpub.com/doi/pdfplus/10.1089/cap.2015.2511

Ellen J Spartz, Mark Freeman Jr, Kayla Brown, Bahare Farhadian, Margo Thienemann, Jennifer Frankovich: ‘Course of Neuropsychiatric Symptoms After Introduction and Removal of Nonsteroidal Anti-Inflammatory Drugs: A Pediatric Observational Study’. Journal of Child and Adolescent Psychopharmacology, July 2017, ahead of print. https://doi.org/10.1089/cap.2016.0179

Kayla D Brown, Cristan Farmer, Mark Freeman Jr, Ellen J Spartz, Bahare Farhadian, Margo Thienemann, Jennifer Frankovich: ‘Effect of Early and Prophylactic Nonsteroidal Anti-Inflammatory Drugs on Flare Duration in Pediatric Acute-Onset Neuropsychiatric Syndrome: An Observational Study of Patients Followed by an Academic Community-Based Pediatric Acute-Onset Neuropsychiatric Syndrome Clinic’. Journal of Child and Adolescent Psychopharmacology, July 2017, ahead of print. https://doi.org/10.1089/cap.2016.0193

Jennifer Frankovich, Margo Thienemann, Jennifer Pearlstein, Amber Crable, Kayla Brown, Kiki Chang: ‘Multidisciplinary Clinic Dedicated to Treating Youth with Pediatric Acute-Onset Neuropsychiatric Syndrome: Presenting Characteristics of the First 47 Consecutive Patients’. Journal of Child and Adolescent Psychopharmacology, 2015;25(1):38–47. DOI: 10.1089/cap.2014.0081. www.ncbi.nlm.nih.gov/pmc/articles/PMC4340335/

Tanya Murphy, Muhammad Sajid, Ohel Soto, Nathan Shapira, Paula Edge, Mark Yang, Mark H Lewis, Wayne K Goodman: ‘Detecting pediatric autoimmune neuropsychiatric disorders associated with streptococcus in children with obsessive-compulsive disorder and tics’. https://pubmed.ncbi.nlm.nih.gov/14706426/

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Dileepan, T., Linehan, J.L., Moon, J.J., Pepper, M., Jenkins, M.K., Cleary, P.P., and Agalliu, D. (2016) ‘Group A Streptococcus intranasal infection promotes CNS infiltration by streptococcal-specific Th17 cells’, Journal of Clinical Investigation, 126(1), pp. 303–317. Available at: https://www.jci.org/articles/view/80792

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