Defining clinical course of patients evaluated for pediatric acute-onset neuropsychiatric syndrome (PANS): phenotypic classification based on 10 years of clinical data

SUMMARY

The Article, “Defining Clinical Course of Patients Evaluated for Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS): Phenotypic Classification Based on 10 Years of Clinical Data” by Masterson et al. presents a comprehensive effort to standardize the clinical classification and terminology associated with PANS. This condition is characterized by the abrupt onset of obsessive-compulsive behaviors and/or eating restrictions, along with at least two additional neuropsychiatric symptoms. Because there are no definitive biological markers for PANS, diagnosis and disease tracking rely heavily on clinical observation. To improve communication across care teams and research efforts, the authors developed a classification framework based on longitudinal data from 264 pediatric patients evaluated at Stanford’s Immune Behavioral Health (IBH) Clinic between 2012 and 2023.

Among the study cohort, 75% met diagnostic criteria for PANS—51% at their initial flare and 24% at a later point—while 25% exhibited PANS-like features but never met full criteria. Flare durations averaged four months, with 95% of isolated flares resolving within a year. However, nearly half of the patients with PANS experienced at least one flare lasting over 12 months, most commonly the initial episode. Based on these patterns, the authors proposed two major clinical course types: Single Flare and Relapsing-Remitting (RR). Each category includes a potential persistent subtype—Primary Persistent for single flares that last over a year without full recovery, and Secondary Persistent for RR cases where patients fail to recover from a later flare. By five years after their initial flare, 77% of patients who met PANS criteria had experienced multiple flares, with most following a relapsing-remitting trajectory. In contrast, patients who never met full PANS criteria were more likely to be classified with a persistent or single-flare course.

This work emphasizes that many children exhibit sub-acute symptom onset prior to meeting PANS criteria, highlighting the importance of early symptom recognition and monitoring. The classification system proposed here is designed to improve diagnostic precision, treatment planning, and clinical trial design. By encouraging consistent terminology around flares, recovery, and disease progression, the study sets a foundation for future research, including the pursuit of biological markers to validate and refine clinical observations.

LINK TO PAPER: https://karger.com/dne/article-pdf/doi/10.1159/000545598/4362556/000545598.pdf