Stroke after bone marrow transplantation: frequency, aetiology and outcome

Few data exist on the frequency, aetiology and outcome of cerebrovascular complications of bone marrow transplantation (BMT). We reviewed all patients undergoing BMT at the Fred Hutchinson Cancer Research Center, Seattle, Wash., USA (a large referral institution) over 3 years. We reviewed ICD-9 (International Classification of Diseases) codes for ischaemic stroke, seizure, intracranial haemorrhage and brain infection. Using standardized forms, we paid detailed attention to clinical features and demographics, oncological diagnosis, conditioning regimens, neurological history, comorbidities, time from BMT to ictus, stroke subtype, radiological and pathological features, and outcomes. We identified 36 patients with stroke from 1245 patients who had BMT (2.9%) over 3 years. These patients' median age was 35 (range 5-60, interquartile range 25-45) years. The most common causes of stroke were intracranial haemorrhage related to thrombocytopenia (38.9%) and infarction or haemorrhage secondary to fungal infection (30.6%). Twenty-five patients (69.4%) died from their stroke; none survived without disability. Using a logistic regression model, we found that neither demographic (e.g. age, gender) nor clinical (e.g. oncological diagnosis, type of BMT, time of stroke after BMT) factors predicted outcome. Stroke occurs relatively frequently (incidence almost 3%) after BMT, has a relatively high frequency of infection-triggered events, has a neurological outcome not easily predicted from available data and is often fatal.