Diffuse White Matter Involvement in Subacute Sclerosing Panencephalitis

A 10-year-old premorbidly normal boy presented with deterioration in school performance and poor attention span for the past 6 months. On examination, he had spasticity and a mini mental state examination score of 17. An magnetic resonance imaging (MRI) of the brain showed revealed diffuse periventricular and subcortical white matter involvement ([Fig. 1]). He had a history of measles like illness at 1 year of age which prompted us to do an electroencephalography despite the absence of myoclonus or seizures. The electroencephalography revealed periodic complexes typical of subacute sclerosing panencephalitis ([Fig. 2]). The cerebrospinal fluid and serum IgG measles antibody titers were elevated (Titer 1:625) confirming the diagnosis of subacute sclerosing panencephalitis (SSPE).[1]

Fig. 1 MRI of the brain showing T1 hypointense (A), T2-weighted (B, C), FLAIR (D,E) hyperintensities in periventricular white matter and subcortical U fiber (patchy). These did not show contrast enhancement (F). There is also thinning of corpus callosum (not shown), cerebral atrophy with prominence of extra-axial cerebrospinal spaces and ventriculomegaly.

Fig. 2 Electroencephalography showing generalized burst of spike-slow wave complex lasting 1 second. These complexes occurred every 4–6 seconds suggestive of periodic complexes (Bipolar montage, sensitivity 15 mcv/mm, sweep speed 30 mm/sec).

MRI changes in SSPE shows initial cortical and subsequent subcortical or periventricular white matter involvement. These changes occur initially in parietal or occipital lobes.[2] In a series, approximately 18% of child with SSPE were misdiagnosed as leucodystrophy or demyelinating disease.[3] Rarely, brainstem and basal ganglia involvement may also be involved in SSPE.[4] [5] To conclude, in any child with rapidly progressive dementia with white matter abnormalities, prior history of measles should be meticulously probed, and SSPE should be evaluated.

Author Contribution

S.R.D. initiated the draft of manuscript, review of literature

J.K.S., N.S., and S.K. were involved in patient management, preparation of the draft, review of literature

P.S. interpreted radiological data and approved manuscript.

L.S. did the critical review and will act as corresponding author/guarantor

Ethical Approval

An informed consent form was signed by the parents of the patient to approve the use of patient information or material for scientific purposes. The patient identity has not been disclosed anywhere in the manuscript and doesn't contain any identifiable images

• References

• 1 Garg RK. Subacute sclerosing panencephalitis. Postgrad Med J 2002; 78 (916) 63-70
• 2 Anlar B, Saatçi I, Köse G, Yalaz K. MRI findings in subacute sclerosing panencephalitis. Neurology 1996; 47 (05) 1278-1283
• 3 Prashanth LK, Taly AB, Sinha S, Ravi V. Subacute sclerosing panencephalitis (SSPE): an insight into the diagnostic errors from a tertiary care university hospital. J Child Neurol 2007; 22 (06) 683-688
• 4 Saini AG, Sankhyan N, Padmanabh H, Sahu JK, Vyas S, Singhi P. Subacute sclerosing panencephalitis presenting as acute cerebellar ataxia and brain stem hyperintensities. Eur J Paediatr Neurol 2016; 20 (03) 435-438
• 5 Tandra HV, Roy PS, Sharma R, Bhatia V, Saini AG. Subacute sclerosing panencephalitis presenting as choreoathetosis and basal ganglia hyperintensities. Neurohospitalist 2018 Doi: 1941874418776902