Subacute sclerosing panencephalitis: Changes in phenotype during the last decade

Introduction: Subacute sclerosing panencephalitis (SSPE) is a rare, progressive, neurodegenerative disease with poor outcome. Anti-measles vaccination contributed to a decreasing number of SSPE patients, but not to its eradication. The aim of our study is to evaluate the course of the disease in our SSPE patients with a focus on vaccinated children. The main goal is considering possibilities for improving prevention of the disease. Methods: A retrospective study included the patients with SSPE treated in the period from December 2010 to December 2020 at the Pediatric Clinic of the Institute. The inclusion criteria were the patients with the diagnosis of SSPE based on clinical presentation, neuroimaging, electroencephalography and positive IgG anti-measles antibodies, both in serum and CSF. Results: Five children with fulminant course of SSPE were included. All these patients were suffering from measles at an early age. Three of them had been vaccinated against measles and two had not. All of them had previously been healthy, immune-competent children, with normal general development. The course was extremely fulminant with lethal outcome within three months since the initial symptoms in four cases. Progressive motor and cognitive decline, behavior changes, movement disorders, myoclonic jerks and seizures were dominant in clinical presentation. Conclusion: Despite vaccination, SSPE has not been eradicated. An increasing number of vaccinated immune-competent children with fulminant form of SSPE and history of measles infection at an early age were treated at our Clinic. As a measure for improving prevention, we suggest considering weaning of vaccine-derived immunity, and re-vaccination of girls at reproductive period.