Dr. Kumar’s Take:
This study from the National Institute of Mental Health (NIMH) explored whether giving antibiotics could prevent strep-triggered neuropsychiatric flares in children with PANDAS. While the approach was well-structured and targeted, the overall results showed only modest benefit. However, for children with a strong pattern of symptom worsening after strep infections, this research supports considering prophylactic antibiotics as part of a carefully monitored plan.
Key Takeaways:
✔ Study included 37 children with PANDAS over a one-year period.
✔ Participants received either penicillin or azithromycin to prevent strep infections.
✔ Antibiotics slightly reduced strep infections, but did not significantly reduce neuropsychiatric flares.
✔ Strict monthly monitoring and symptom scoring were used to track changes.
✔ If a child developed a strep infection during the study, their study antibiotic was paused and treated with another class of antibiotic.
Actionable tip:
If your child’s OCD or tics tend to worsen after confirmed strep infections, talk to your doctor about whether short-term antibiotic prevention during high-risk periods (like strep outbreaks at school) could be helpful.
Brief Summary:
This double-blind study followed 37 children diagnosed with PANDAS—a condition where strep infections are linked to sudden-onset OCD or tics. Children were randomly given either penicillin or azithromycin to see if preventing strep infections could also prevent psychiatric flare-ups. Over the year, researchers found a small drop in strep infections in the antibiotic groups, but the reduction in neuropsychiatric symptoms was not statistically significant. Nevertheless, the study confirmed that strep can play a triggering role in PANDAS, and that close monitoring and antibiotic strategies may help some children.
Study Design:
- Type: Randomized, double-blind, placebo-controlled
- Participants: Children with a history of PANDAS, aged under puberty, with documented symptom flares linked to strep
- Groups:
- Penicillin V-K: 250 mg twice daily
- Azithromycin: 250 mg once weekly (plus placebo on other days)
- Duration: 1 year
- Monitoring: Monthly throat cultures, antibody titers (ASO and anti-DNase B), and psychiatric assessments using CY-BOCS and YGTSS scales
- Compliance: Capsules were blister packed, and parents reported missed doses monthly
Results:
- GAS infections: Slightly reduced in antibiotic groups compared to baseline year
- Neuropsychiatric symptom exacerbations: No statistically significant reduction during the treatment year
- Compliance: Improved compared to previous studies due to better capsule tracking
- Safety: No major adverse events reported; subjects with breakthrough strep were switched to non-study antibiotics temporarily
How Do Antibiotics Help in PANDAS?
The theory behind prophylactic antibiotics in PANDAS is simple: if you can prevent strep infections, you might stop the abnormal immune reaction that inflames the brain and triggers OCD or tic symptoms. This study provided partial support for that idea, though it also highlighted the complexity of immune-neuropsychiatric interactions and the need for targeted treatments.
Related Studies and Research
PANS and Corticosteroids: A Study Review – Reviews outcomes of corticosteroid use during PANS flares.
Plasma Apheresis for Severe PANDAS Symptoms – Analyzes therapeutic plasma exchange in children with severe PANDAS.
PANDAS OCD Treatment Overview – Summarizes current treatment strategies for PANDAS-related OCD.
Podcast: Could Your Child’s Behavior Changes Be Cured with an Antibiotic? – A deep dive into the link between strep infections and dramatic neuropsychiatric symptoms.
Frequently Asked Questions
Why were two antibiotics tested?
Penicillin and azithromycin were chosen because they both treat strep infections effectively but work in different ways. Researchers wanted to see if either one was more effective at preventing symptom flare-ups.
Were kids taken off the study drugs if they got strep?
Yes. If a child got a confirmed strep infection, they were taken off their study antibiotic temporarily and given a different antibiotic to treat the active infection.
Did the antibiotics improve OCD or tic symptoms directly?
Not directly. The antibiotics were used to prevent strep infections. The theory was that fewer infections might lead to fewer psychiatric symptoms.
Should all kids with PANDAS be on antibiotics year-round?
Not necessarily. This study does not support routine year-round antibiotic use for all children with PANDAS. It’s a decision that should be made on a case-by-case basis with a knowledgeable physician.
Conclusion
While this study did not show a dramatic benefit of year-long antibiotic prophylaxis for PANDAS, it reinforces the idea that strep infections can trigger psychiatric symptoms in some children. If your child shows a clear pattern of flare-ups after strep, discuss this study with your pediatrician or a specialist. Short-term antibiotic strategies or immune-focused treatments might be helpful, especially when personalized to your child’s unique history.