PANDAS and PANS

What PANDAS and PANS are

PANDAS was described in the 1990s at the National Institute of Mental Health. The theory is that in some children, antibodies made against group A Streptococcus also react with parts of the brain, especially the basal ganglia, an idea called molecular mimicry. This is similar to how strep causes Sydenham chorea, a recognized movement disorder of rheumatic fever.

PANS was defined later to include children with the same abrupt pattern but without a clear strep link. Possible triggers include other infections (such as Mycoplasma, influenza and others), metabolic or inflammatory conditions, and sometimes no identifiable trigger.

How often these conditions occur, and how best to diagnose and treat them, remains debated, partly because strep infections and OCD are both common in children.

Symptoms

Core symptoms

• sudden, dramatic onset of obsessive-compulsive symptoms, often over 24 to 72 hours
• for PANS, sudden severe food restriction may be the main feature
• for PANDAS, tics may be prominent

Additional symptoms

At least two of the following, often appearing together:

• severe anxiety, especially separation anxiety
• emotional lability or depression
• irritability, aggression or oppositional behavior
• behavioral regression, acting much younger
• decline in school performance, attention or memory
• sensory or motor problems: sensitivity to light, sound or textures, handwriting deterioration, tics
• sleep problems
• urinary frequency or new bedwetting

Course

Symptoms often follow a relapsing-remitting course, with flare-ups linked to new infections, separated by periods of partial improvement.

Diagnostic criteria

Both are diagnoses of exclusion: other conditions, such as Sydenham chorea, autoimmune encephalitis, lupus, Tourette syndrome, typical OCD and eating disorders, must be considered.

Diagnosis

• detailed history, focused on how suddenly symptoms began and any preceding infections
• examination, including neurological examination
• throat swab for strep, and possibly strep antibody tests (ASO, anti-DNase B), although positive antibodies alone do not prove PANDAS
• tests for other infections when indicated
• blood tests for inflammation and other autoimmune conditions
• psychiatric evaluation
• sometimes MRI, EEG or lumbar puncture if encephalitis or other neurological disease is suspected

Treatment

Treatment typically addresses three areas.

Treating infection

• antibiotics for an active strep throat or other confirmed infection
• some clinicians use longer-term preventive antibiotics in children with recurrent strep-linked flares, though evidence is limited

Treating symptoms

• cognitive behavioral therapy with exposure and response prevention for OCD
• SSRIs for OCD and anxiety, often started at low doses because some children are sensitive to side effects
• support for eating, sometimes with a dietitian or eating disorder team
• school accommodations during flares
• family support and parent guidance

Immune-modulating treatment

For moderate to severe or persistent cases, some specialists use:

• NSAIDs during flares
• short courses of corticosteroids
• IV immunoglobulin or plasma exchange for severe cases

These treatments are used based on expert consensus and limited trial data. They should be guided by specialists.

Outlook

Many children improve substantially, especially with prompt treatment, though some have flares for months or years. Long-term outcomes vary, and some children go on to have chronic OCD or tic disorders.

Frequently asked questions

What is PANDAS?

PANDAS stands for pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections. It describes children who suddenly develop OCD symptoms or tics after a strep infection, thought to be caused by an immune reaction affecting the brain.

What is the difference between PANDAS and PANS?

PANDAS requires a link to group A strep infection and features OCD or tics. PANS is broader: it includes children with sudden OCD or severe eating restriction plus other neuropsychiatric symptoms, triggered by various infections or other causes, or no identifiable trigger.

What are the symptoms of PANDAS?

The hallmark is a sudden, dramatic onset of obsessions, compulsions or tics. Other common symptoms include severe anxiety, separation anxiety, mood swings, irritability, regression, worsening handwriting, sensory sensitivity, sleep problems and new bedwetting.

Is PANDAS a real diagnosis?

PANDAS and PANS are recognized by the National Institute of Mental Health and many specialists, but their causes, how common they are and the best treatments remain debated. Diagnosis relies on clinical criteria and excluding other conditions. Families benefit from clinicians experienced with these syndromes.

How is PANDAS treated?

Treatment includes antibiotics for any active strep infection, cognitive behavioral therapy and sometimes SSRIs for OCD and anxiety, and in selected moderate to severe cases, anti-inflammatory or immune-based treatments such as steroids or IV immunoglobulin guided by specialists.