@article{CadarJellingerRiedereretal.2021, author = {Cadar, D{\´a}niel and Jellinger, Kurt A. and Riederer, Peter and Strobel, Sabrina and Monoranu, Camelia-Maria and Tappe, Dennis}, title = {No metagenomic evidence of causative viral pathogens in postencephalitic parkinsonism following encephalitis lethargica}, series = {Microorganisms}, volume = {9}, journal = {Microorganisms}, number = {8}, issn = {2076-2607}, doi = {10.3390/microorganisms9081716}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-245074}, year = {2021}, abstract = {Postencephalitic parkinsonism (PEP) is a disease of unknown etiology and pathophysiology following encephalitis lethargica (EL), an acute-onset polioencephalitis of cryptic cause in the 1920s. PEP is a tauopathy with multisystem neuronal loss and gliosis, clinically characterized by bradykinesia, rigidity, rest tremor, and oculogyric crises. Though a viral cause of EL is likely, past polymerase chain reaction-based investigations in the etiology of both PEP and EL were negative. PEP might be caused directly by an unknown viral pathogen or the consequence of a post-infectious immunopathology. The development of metagenomic next-generation sequencing in conjunction with bioinformatic techniques has generated a broad-range tool for the detection of unknown pathogens in the recent past. Retrospective identification and characterization of pathogens responsible for past infectious diseases can be successfully performed with formalin-fixed paraffin-embedded (FFPE) tissue samples. In this study, we analyzed 24 FFPE brain samples from six patients with PEP by unbiased metagenomic next-generation sequencing. Our results show that no evidence for the presence of a specific or putative (novel) viral pathogen was found, suggesting a likely post-infectious immune-mediated etiology of PEP.}, language = {en} }