Neurological manifestations of chronic graft-versus-host disease after allogeneic haematopoietic stem cell transplantation: report from the Consensus Conference on Clinical Practice in chronic graft-versus-host disease.

A major obstacle of allogeneic haematopoietic stem cell transplantation is graft-versus-host disease, an immune-mediated disorder that affects multiple tissues and organs with varying severity. Neurological complications of acute and chronic graft-versus-host disease are rare but can produce severe clinical problems with significant morbidity and mortality. In this article, we review neurological manifestations of chronic graft-versus-host disease that comprise immune-mediated neuropathies, myasthenia gravis and myositis in the peripheral nervous system and various cerebrovascular complications, demyelination and immune-mediated encephalitis in the central nervous system. The National Institutes of Health consensus on criteria for clinical trials in chronic graft-versus-host disease recommended that the diagnosis of chronic graft-versus-host disease of the nervous system can be made only when other organs are affected by graft-versus-host disease and frequent neurological differential diagnoses such as drug-induced toxicities or opportunistic infections are excluded. The Consensus Conference on Clinical Practice in chronic graft-versus-host disease, held in autumn 2009 in Regensburg, aimed to summarize the literature and to provide guidelines for the diagnostic approach in children and adults with neurological manifestations of chronic graft-versus-host disease. Moreover, we present therapeutic recommendations and their level of evidence for the management of these complications. Overlapping symptoms and comorbidities after allogeneic haematopoietic stem cell transplantation and the limited knowledge about the underlying biological mechanisms of chronic graft-versus-host disease affecting the nervous system emphasize the need for further experimental and clinical investigations.