What is the appropriate diagnosis and treatment for Pediatric Acute-onset Neuropsychiatric Syndrome (PANS)?

Diagnosis and Treatment of Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS)

The most appropriate approach to PANS is a three-tiered treatment protocol based on symptom severity, with accurate diagnosis requiring both the presence of acute-onset obsessive-compulsive disorder (OCD) or severely restricted food intake, plus at least two additional neuropsychiatric symptoms. 1

Diagnostic Criteria for PANS

• Core criteria:

  • Abrupt, dramatic onset of OCD or severely restricted food intake
  • Concurrent presence of at least TWO additional neuropsychiatric symptoms with similarly severe and acute onset:
    • Anxiety
    • Emotional lability or depression
    • Irritability, aggression, or severely oppositional behaviors
    • Behavioral regression
    • Deterioration in school performance
    • Sensory or motor abnormalities
    • Somatic signs including sleep disturbances, enuresis, or urinary frequency

• Additional diagnostic requirements:

  • Symptoms not better explained by a known neurological or medical disorder
  • Age of onset typically between 3-12 years

Diagnostic Workup

1. Infectious disease evaluation:

   • Throat culture and rapid strep test
   • Anti-streptolysin O (ASO) and anti-DNase B titers
   • Testing for other potential infectious triggers (viral panels, Mycoplasma, Lyme disease) 2

2. Immunological assessment:

   • Complete blood count with differential
   • Inflammatory markers (ESR, CRP)
   • Autoimmune panels including antinuclear antibodies
   • Immunoglobulin levels (IgG, IgA, IgM) 1

3. Neurological evaluation:

   • Consider MRI brain if neurological symptoms present
   • EEG if seizure-like activity is observed 3

4. Psychiatric assessment:

   • Comprehensive evaluation of OCD symptoms, tics, anxiety, and other behavioral changes
   • Rule out other primary psychiatric disorders 4

Treatment Protocol Based on Symptom Severity

1. Mild PANS Symptoms

• First-line treatment:
  • Supportive care with cognitive behavioral therapy
  • NSAIDs for inflammatory symptoms
  • Short oral corticosteroid bursts (prednisone 1-2 mg/kg/day for 5-7 days) if symptoms persist 1
  • Appropriate antibiotics if streptococcal or other bacterial infection is confirmed 2

2. Moderate-to-Severe PANS Symptoms

• First-line treatment:
  • Oral or intravenous corticosteroids (methylprednisolone 15-30 mg/kg/day for 3-5 days)
  • Intravenous immunoglobulin (IVIG) 1-2 g/kg divided over 2 days 1
  • Antibiotics for confirmed infections
  • Psychiatric medications for symptom management (SSRIs for OCD, antipsychotics for severe behavioral disturbances)

3. Extreme/Life-Threatening PANS Symptoms

• First-line treatment:
  • Therapeutic plasma exchange (5-6 exchanges over 7-10 days)
  • May be combined with IVIG and high-dose IV corticosteroids
  • Consider rituximab for refractory cases 1
  • Intensive psychiatric support

Infection Management and Prevention

• For PANDAS (streptococcal-triggered PANS):

  • Initial anti-streptococcal treatment for all newly diagnosed cases
  • Consider prophylactic antibiotics for children with recurrent streptococcal-associated exacerbations 2

• For non-streptococcal PANS:

  • Monitor closely for intercurrent infections
  • Promptly treat any identified infections according to standard guidelines 2
  • Maintain vigilance for streptococcal infections in patients and close contacts

Clinical Course and Monitoring

• PANS typically follows a relapsing-remitting course 4
• Monitor for symptom exacerbations, particularly following infections
• Assess treatment response using standardized rating scales for OCD, anxiety, and other neuropsychiatric symptoms
• Regular follow-up with multidisciplinary team including pediatric neurology, psychiatry, and immunology/rheumatology

Important Considerations

• Family history of autoimmune diseases or neuropsychiatric disorders is common in PANS patients (approximately 48% for each) 4
• Many PANS patients (74%) have pre-existing developmental disorders or symptoms 4
• Bacterial infections (particularly streptococcal) and viral infections are commonly associated with symptom onset 4
• Antibiotics may be beneficial beyond their antimicrobial effects in some patients 4

PANS remains a clinical diagnosis without definitive biomarkers, requiring careful exclusion of other medical and psychiatric conditions. Treatment should be tailored to symptom severity, with immunomodulatory therapies reserved for cases with evidence of neuroinflammation or post-infectious autoimmunity.