Staging/typing of Lewy body related alpha-synuclein pathology

When 22 members of the BrainNet Europe (BNE) consortium assessed 31 cases with a-synuclein (aS) immunoreactive (IR) pathology applying the consensus protocol described by McKeith and colleagues in 2005, the inter-observer agreement was 80%, being lowest in the limbic category (73%). When applying the staging protocol described by Braak and colleagues in 2003, agreement was only 65%, and in some cases as low as 36%. When modifications of these strategies, i.e., McKeith’s protocol by Leverenz and colleagues from 2009, Braak’s staging by Müller and colleagues from 2005 were applied then the agreement increased to 78 and 82%, respectively. In both of these modifications, a reduced number of anatomical regions/blocks are assessed and still in a substantial number of cases, the inter-observer agreement differed significantly. Over 80% agreement in both typing and staging of aS pathology could be achieved when applying a new protocol, jointly designed by the BNE consortium. The BNE-protocol assessing aS-IR lesions in nine blocks I. Alafuzoff, P. Ince, J. Bell, J. Ironside, S. Gentleman, H. Kretzschmar did primary assessment of all cases; I. Alafuzoff, P. Ince the construction of the assessment recommendations. Each listed author carried out the assessment and contributed to manuscript revision. A. Rozemuller Netherlands Brain Bank, VU University Medical Center, Amsterdam, The Netherlands N. Kavantzas P. Korkolopoulou E. Patsouris Department of Pathology, National and Capodistrian University of Athens, Athens, Greece I. Ferrer E. Gelpi Institut de Neuropatologia, Universitat de Barcelona, Barcelona, Spain P. Parchi Dipartimento di Scienze Neurologiche, Università di Bologna, Bologna, Italy J. Bell J. W. Ironside Department of Pathology, University of Edinburgh, Western General Hospital, Edinburgh, UK C. Stadelmann-Nessler Georg-August-Universitaet Goettingen, Göttingen, Germany N. Bogdanovic Department of Geriatrics, Karolinska Institutet, Huddinge, Sweden I. Alafuzoff L. Parkkinen Department of Neuroscience and Neurology, Kuopio University, Kuopio, Finland S. Gentleman Neuropathology Unit, Department of Clinical Neuroscience, Imperial College, London, UK S. Al-Sarraj I. Bodi A. King Department of Clinical Neuropathology, London Institute of Psychiatry, London, UK D. Meyronet N. Streichenberger Faculté de Médecine Laennec Hospices Civils de Lyon, Centre de Neuropathologie et Pathologie-Est, Université Lyon 1, Lyon, France O. Bugiani G. Giaccone Fondazione IRCCS Istituto Neurologico Carlo Besta, Milan, Italy T. Arzberger H. Kretzschmar Centre for Neuropathology and Prion Research, Ludwig-Maximilians-University, Munich, Germany 123 Acta Neuropathol (2009) 117:635–652 DOI 10.1007/s00401-009-0523-2