Hematopoietic
cell transplantation (HCT) is the preferred treatment for an expanding range of neoplastic and nonmalignant conditions. Increasing numbers of solid
organ transplantations (SOTs) add an additional population of immunosuppressed patients with multiple potential neurological problems. While the spectrum of neurological complications varies with conditioning procedure and hematopoietic cell or solid organ source, major neurological complications occur with all
transplantation procedures. This 2 part review emphasizes a practical consultative approach to central and peripheral nervous system problems related to HCT or SOT with clinical and neuroimaging examples from the authors' institutional experience with the following conditions: the diversity of manifestations of common
infections such as varicella zoster virus, Aspergillus, and
progressive multifocal leukoencephalopathy (PML),
drug therapy-related complications,
stroke mechanisms, the spectrum of
graft versus host disease (GVHD), and neurologically important syndromes of
immune reconstitution inflammatory syndrome (IRIS),
posterior reversible encephalopathy syndrome (PRES), and posttransplantation
lymphoproliferative disorder (PTLD). These complications preferentially occur at specific intervals after HCT and SOT, and neurological consultants must recognize an extensive spectrum of syndromes in order to effect timely diagnosis and expedite appropriate treatment.