title: Subacute sclerosing panencephalitis presenting as acute cerebellar ataxia and brain stem hyperintensities.
abstract: BACKGROUND
  Subacute sclerosing panencephalitis is a devastating neurodegenerative disease with a characteristic clinical course. Atypical presentations may be seen in 10% of the cases.
  
  
  OBJECTIVE
  To describe the atypical clinical and radiological features of SSPE in a child form endemic country.
  
  
  METHODS
  A 5-year-old boy presented with acute-onset cerebellar ataxia without associated encephalopathy, focal motor deficits, seizures or cognitive decline. He had varicella-like illness with vesicular, itchy truncal rash erupting one month prior to the onset of these symptoms. He underwent detailed neurological assessment, relevant laboratory and radiological investigations.
  
  
  RESULTS
  Neuroimaging revealed peculiar brain stem lesions involving the pons and cerebellum suggestive of demyelination. With a presumptive diagnosis of clinically isolated syndrome of demyelination, he was administered pulse methylprednisolone (30 mg/kg/day for 5 days). Four weeks later he developed myoclonic jerks. Electroencephalogram showed characteristic periodic complexes time-locked with myoclonus. CSF and serum anti-measles antibody titres were elevated (1:625).
  
  
  CONCLUSIONS
  Our report highlights that subacute sclerosing panencephalitis can present atypically as isolated acute cerebellar ataxia and peculiar involvement of longitudinal and sparing of transverse pontine fibres. The predominant brainstem abnormalities in the clinical setting may mimick acute demyelinating syndrome. Hence, it is important to recognize these features of subacute sclerosing panencephalitis in children, especially in the endemic countries.
authors.affiliation: Pediatric Neurology and Neurodevelopment Unit, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Arushi Gahlot
authors.initials: AG
authors.lastname: Saini
authors.affiliation: Pediatric Neurology and Neurodevelopment Unit, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Naveen
authors.initials: N
authors.lastname: Sankhyan
authors.affiliation: Pediatric Neurology and Neurodevelopment Unit, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Hansashree
authors.initials: H
authors.lastname: Padmanabh
authors.affiliation: Pediatric Neurology and Neurodevelopment Unit, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Jitendra Kumar
authors.initials: JK
authors.lastname: Sahu
authors.affiliation: Department of Radiodiagnosis, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India.
authors.forename: Sameer
authors.initials: S
authors.lastname: Vyas
authors.affiliation: Pediatric Neurology and Neurodevelopment Unit, Advanced Pediatrics Centre, Post Graduate Institute of Medical Education and Research, Chandigarh 160012, India. Electronic address: doctorpratibhasinghi@gmail.com.
authors.forename: Pratibha
authors.initials: P
authors.lastname: Singhi
mesh_terms: D000208:Acute Disease; D001933:Brain Stem / Q000000981:diagnostic imaging / Q000473:pathology; D002524:Cerebellar Ataxia / Q000000981:diagnostic imaging / Q000209:etiology*; D002675:Child, Preschool; D004569:Electroencephalography; D006801:Humans; D008297:Male; D009207:Myoclonus / Q000209:etiology / Q000473:pathology; D059906:Neuroimaging; D009460:Neurologic Examination; D012640:Seizures / Q000453:epidemiology / Q000473:pathology; D013344:Subacute Sclerosing Panencephalitis / Q000150:complications* / Q000175:diagnosis*
keywords: Acute ataxia; Brain stem hyperintensities; Myoclonus; Neurodegenerative; Periodic complexes; Subacute sclerosing panencephalitis