SSPE (Subacute sclerosing panencephalitis) - the great masquerader

Background: SSPE is chronic progressive encephalitis affecting children and young adults which usually presents with cognitive decline and behavioural changes followed by periodic myoclonic jerks, seizures, vision loss and ataxia. High degree of suspicion is required as the presentation can be variable and can have many differentials. Aim: We aim to study various presentations of SSPE Methods and Material: Retrospective study was done to analyse various presentations in patients diagnosed with SSPE as per modied Dykens criteria from a tertairy care centre over a period of 2 years (1st January 2018-31st December 2020). Results: 6 cases of SSPE were identied. Case1 - 22 months old presented with subacute history of ataxia, multical myoclonus and developmental regression. Gradually myoclonus worsened to involve trunk and developed drop attacks. Case 2 - 17 years boy presented with single episode of seizure. Case 3- 25 years female with 5 months gestation presented with subacute vision loss followed by progressive cognitive decline, behavioural changes, Parkinsonism, Dystonia and stimulus sensitive myoclonus. Case4- 28 years female presented with rapidly progressive cognitive decline and behavioural changes. Case 5- 32 years male presented with history of myoclonic jerks and dropping of objects. Gradually developed progressive behavioural changes and cognitive decline and became vegetative. Case6 - 9 year old child presented with faciobrachial seizures (myoclonic jerks) and scholastic backwardness. Conclusions: SSPE can manifest with varied presenting complaints. Also, Results of EEG, MRI and CSF examination can change during the disease course. Therefore, high degree of suspicion is required for early diagnosis of this challenging entity.