Antibiotics for PANDAS? Limited evidence: review and putative mechanisms of action

Objective: Antibiotics have been used extensively by clinicians to treat patients with PANDAS or PANS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections and pediatric acute-onset neuropsychiatric syndrome, respectively). This review examines the best-quality evidence supporting the practice-based use of antibiotics in these psychiatric conditions. Data Sources: PubMed was searched for English-language articles published between January 1994 and July 2017 using the search terms [PANDAS OR PANS OR new-onset pediatric OCD] AND [antibiotics OR macrolides OR beta-lactams]. Study Selection: Randomized clinical trials, observational studies, and case reports concerning antibiotic use in PANDAS/PANS were reviewed. Four publications were included in the quantitative synthesis. Data Extraction: The evidence was rated using the GRADE (Grading of Recommendations, Assessment, Development, and Evaluation) method. Results: Although the single studies conveyed no statistically significant results, there is some evidence for efficacy of antibiotic therapy in reducing neuropsychiatric symptoms in the PANDAS/PANS population. Conclusions: Whereas the use of eradicating antibiotic therapy during active infections in PANDAS/PANS is well established, there is still a need for studies that improve the quality of evidence supporting use of antibiotics in this population independent of ongoing infections. Studies that compare antibiotics with other therapies, as well as studies that assess safety and efficacy of long-term use of antibiotic therapy in PANDAS/PANS, are still lacking. However, the available research supports evidence of a subgroup in the pediatric OCD population that is sensitive to antibiotic treatment and immunomodulatory therapy, independent of ongoing infectious conditions. Thus, more studies are warranted in the overall OCD spectrum.