Abstract
Purpose: :
Sporadic Creutzfeldt-Jacob disease (sCJD) is a rare neurodegenerative illness comprising five phenotypically distinct subtypes based on the methionine(M)/valine(V) polymorphism at codon 129 of the prion protein (PrP) gene and presence of either one of the two protease-resistant PrP (PrPres), referred to as PrPres type 1 and type 2.1, 2 The most common of these five subtypes includes the sCJDMM(MV)1 that matches the "classic" sCJD and comprises the so-called Heidenhain variant (HsCJD) characterized by early and prominent visual symptoms. Recently, an additional subtype of sCJD has been described and identified as sCJDMM1-2 in which both types 1 and 2 histopathological changes are found in the same brain.3 The clinical Heidenhain phenotype in association with histopathological sCJDMM1-2 subtype has not been described before.
Methods: :
Clinical, neuroimaging, EEG findings, histopathological and immunostaining as well as PrPres characterization of 20 cases of sCJDMM1-2 were reviewed.
Results: :
Two cases (10%) of HsCJD with ages at onset of 51 and 66 years and disease durations of 4 and 12 months were identified. Immunohistopathology and PrPres type determination were consistent with the features of the sCJDMM1-2 subtype.3 The visual cortex was more severely affected than the frontal cortex and was found to carry both PrPres types.4 The study of the quantitative distribution of PrPres types, expressed as mean percentage of total PrPres types 1 and 2 (1:2), was 79%:21% for the sCJDMM1-2 with 4 month and 45%:55% for the case with 12 months disease duration respectively. The cerebellum showed both PrPres types and PrP immunohistochemical patterns of the sCJDMM1-2.
Conclusions: :
To our knowledge, this is the first histopathological finding of sCJDMM1-2 in Heidenhain variant of sporadic CJD.Also, the amount of PrPres type 2 and to a lesser extent that of the MM2-like immunohistochemical features increase with the disease duration, as seen for the sCJDMM1-2, which may have prognostic implications.
Keywords: neuro-ophthalmology: diagnosis • immunohistochemistry • pathology: human