Abstract TP178: Cerebral Infarction after Hematopoietic Stem Cell Transplantation (HSCT) in Adult Patients with Sickle Cell Disease

Abstract

Introduction: Symptomatic and silent cerebral infarcts (SCIs) are common in children and adults with sickle cell disease (SCD). SCIs are associated with cognitive performance and risk of future symptomatic stroke. The incidence of overt stroke and SCI post HSCT is low in children, but there is limited information in adults. We sought to determine the impact of HSCT on the rate of new symptomatic and silent cerebral infarcts in adults with SCD. Methods: The study population included patients with SCD (HbSS, HbSC, and HbS/beta-thalassemia) that were enrolled in NIH studies (14-H-0077, 09-H-0225) and underwent HSCT from 2004-19 and received pre- and post-transplant MRI studies. MRI FLAIR, T1, and T2 images were reviewed by two independent readers and scored for presence of prior ischemic stroke and silent cerebral infarct (≥ 3mm on T2 or FLAIR images in 2 imaging planes). Changes in SCIs and ischemic strokes were compared before and after transplantation. Results: Eighty-four patients were included in the study, mean age 32.3 yrs. (range 10-65 yrs.) and 57% male. Median follow-up period was 3.3 yrs. (range: 6 months -17 yrs.) for a total of 412 patient-years. Overall, 60% had evidence of SCI and or prior ischemic stroke at transplant; 54% (45/84) with SCI and 23% with imaging evidence of a prior stroke. During the follow-up period, 13% (11/84) patients developed new ischemic injury, two patients developed a new stroke and nine patients developed new SCIs. The post-HSCT incidence rate of new stroke was 0.49 events/100 patient-years, and SCIs was 2.2 events/100 patient-years. Patients who progressed compared to those who did not were older at transplant (36.1 yrs. vs. 31.2 yrs.; p=0.09), had a prior history of stroke (27% vs. 22%, p=0.71), had a prior history of SCI (64% vs. 52%, p=0.47), and a prior history of stenotic vasculopathy (18% vs. 14%, p= 0.65). Conclusions: The incidence of new ischemic events after HSCT for SCD in adults is low. Our rates are comparable to incidence rates reported in children with SCD after HSCT. While rates of progression were higher in patients with prior stroke, SCI, and vasculopathy, we did not find a significant difference between groups.