Therapeutic plasma exchange in children with acute demyelination

The discovery of specific biomarkers signaling antibody-related etiologies for severe CNS inflammatory disease has led to a marked change in diagnostic and treatment practices related to these disorders. In the pediatric population, more often than not, neuroinflammation may lead to severe clinical manifestations, including bilateral, severe optic neuritis with total visual loss or transverse myelitis with flaccid paresis of all extremities. While high-dose pulse methylprednisolone is used with benefit in the majority of children,¹ some patients do not respond to this therapy. Importantly, some individuals with antibody-mediated neuroinflammatory disorder such as aquaporin-4 (AQP-4)–related disease (neuromyelitis optica spectrum disorder) may even experience irreversible motor and visual disability after the first event.² Whether this disability can be prevented by early and aggressive acute therapy has been of interest to the clinical community, because studies in adult populations with neuroinflammatory disease suggest that greater benefit is associated with earlier use of therapeutic plasma exchange (TPE).³ Concomitant with this has been the rise of the use of TPE in pediatric neuroinflammatory diseases, but to date, reports have been limited to smaller case series.⁴ Of importance, knowledge about the timing of TPE after acute presentation of neuroinflammation in youth is limited. Clinicians are therefore faced with the following unanswered questions when caring for an acutely ill child: Should I escalate therapy, and when? How late is too late? How safe is TPE in this population?