Symptom-guided approach to central nervous system complications in allogeneic hematopoietic cell transplant recipients: Best practice recommendations from the EBMT Practice Harmonisation and Guidelines committee

Central nervous system complications (CNSC) after allogeneic hematopoietic cell transplantation (allo-HCT) are relatively common and may have a major impact on patients´ outcomes. Neurological symptoms may occur at any point during the post-transplant course, although they are more common early after HCT, with a wide range of possible presentations. As many of CNSC symptoms are non-specific, the initial assessment is often difficult, and early decisions regarding the diagnostic work-up can influence the identification of the underlying cause. Blood tests, neuroimaging and cerebrospinal fluid (CSF) analyses are particularly important, as they frequently provide the first clues that help narrow the very wide differential diagnoses. In view of these challenges, an international EBMT working group composed of haematologists, infectious disease specialists, neurologists, a neuroradiologist, and a microbiologist developed symptom-based recommendations for the early evaluation of CNSC after allo-HCT. The work summarizes key aspects of the clinical presentation and outlines practical steps for the initial diagnostic approach. These recommendations are intended to support haematologists, who are usually the first to assess these patients, in promptly recognizing CNSC so to start timely appropriate management.