The exact causes of PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections) and PANS (Pediatric Acute-onset Neuropsychiatric Syndrome) are not fully understood, but they are believed to involve an immune response triggered by various factors. Here’s a brief overview:

PANDAS (Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections):

1. Streptococcal Infections: PANDAS is associated with infections caused by group A streptococcal bacteria, particularly those that lead to illnesses like strep throat. The theory is that in some individuals, the body’s immune system responds to the streptococcal infection by producing antibodies. In some cases, these antibodies may mistakenly target and affect the brain, leading to neuropsychiatric symptoms.

PANS (Pediatric Acute-onset Neuropsychiatric Syndrome):

1. Infectious Triggers: PANS is a broader term that includes a range of infectious triggers beyond streptococcal infections. Viral infections, mycoplasma infections, and other bacterial infections have been implicated. It’s believed that the immune response to these infections may, in some cases, lead to an inflammatory reaction that affects the brain.
2. Non-Infectious Triggers: PANS can also be triggered by non-infectious factors, such as metabolic or environmental triggers. These may include exposure to certain toxins, stressors, or other immune system triggers.

Common Issues:

1. Autoimmune Response: Both PANDAS and PANS involve an autoimmune response, where the immune system mistakenly attacks the body’s tissues, particularly in the brain.
2. Basal Ganglia Involvement: The basal ganglia, a part of the brain involved in motor control and other functions, is often implicated in these disorders. It’s thought that the immune response affects the basal ganglia, leading to neuropsychiatric symptoms like obsessive-compulsive disorder (OCD) and tic disorders.

Diagnosis and Treatment:

Diagnosing PANDAS and PANS can be challenging, and healthcare professionals typically consider a combination of clinical history, symptom presentation, and laboratory tests. Treatment may involve addressing the underlying infection (if present) with antibiotics, as well as using therapies such as cognitive-behavioral therapy (CBT) and medications to manage symptoms.

Neither PANDAS nor PANS are listed as a diagnosis in the 2013 fifth version of the Diagnostic and Statistical Manual of Mental Disorders (DSM 5) or confirmed as distinct disorders. PANDAS is mentioned in the World Health Organization‘s ICD-11, effective in 2022, under autoimmune central nervous system disorders, but diagnostic criteria are not defined and no specific code for PANS or PANDAS is given.

The 2021 European clinical guidelines developed by the European Society for the Study of Tourette syndrome (ESSTS) did not support the additions made to ICD-11

If you suspect PANDAS or PANS in a child, it’s crucial to seek evaluation and guidance from a healthcare professional, often a pediatrician, neurologist, or specialist in child psychiatry.