Childhood primary angiitis of the central nervous system: Identifying disease trajectories and early risk factors for persistently higher disease activity

OBJECTIVE: To compare clinical, laboratory, and imaging characteristics of childhood primary angiitis of the central nervous system (PACNS) subtypes at diagnosis and during followup; to characterize disease activity trajectories in childhood PACNS subtypes; and to identify early risk factors for higher disease activity. METHODS: We performed a single-center cohort study of consecutive children diagnosed as having childhood PACNS. Demographic, clinical, laboratory, and imaging data were collected at diagnosis and during standardized clinic visits. Outcome measures included disease activity measured by physician's global assessment. Descriptive statistics were used to assess characteristics of the study cohort, and longitudinal data were analyzed using linear mixed-effects regression. RESULTS: The study cohort consisted of 45 patients with childhood PACNS; 26 had angiography-negative childhood PACNS and 19 had angiography-positive childhood PACNS. There were 24 females, the median age at diagnosis was 9.8 years, and the median followup period was 1.8 years. Patients with angiography-negative childhood PACNS were more likely to be female and to present with seizures, cognitive dysfunction, vision abnormalities, high levels of inflammatory markers, and bilateral findings on magnetic resonance imaging (MRI). Motor deficits and ischemic MRI lesions were more common in angiography-positive disease. Disease activity decreased significantly after treatment in all patients. Distinct trajectories of disease activity over time were identified for both childhood PACNS subtypes. Patients with angiography-negative childhood PACNS had persistently higher disease activity. Seizures at presentation also predicted higher disease activity over time. CONCLUSION: Distinct subtypes of childhood PACNS have unique disease activity trajectories. Patients with angiography-negative disease and seizures at presentation experience higher disease activity. Early recognition of this high-risk cohort may enable the treating physician to initiate targeted therapies and prevent long-term brain injury.