MRI manifestations of immunosuppressive drugs associated encephalopathy after allogeneic hematopoietic stem cell transplantation in children with aplastic anemia

Abstract

Objective To summarize the MRI manifestations of immunosuppressive drugs associated encephalopathy after allogeneic hematopoietic stem cell transplantation (allo-HSCT) in children with aplastic anemia. Methods Fifteen patients with immunosuppressive drugs associated encephalopathy after allogeneic hematopoietic stem cell transplantation for aplastic anemia during January 2014 to October 2016 were analyzed retrospectively. There were 7 males and 8 females, aged from 3 to15 years old, with the median age of 7 years old. Ten cases presented dizziness and headache while other 4 cases presented blurred vision, blind and gaze. Only one case suffered from seizure and loss of consciousness. MRI patterns including distribution, morphology and signal intensity were analyzed after treatment. Follow up MRI were performed after reducing drug dose and symptom remission. The duration of immunosuppressive drugs associated encephalopathy of the 15 cases were 1-14 months, with 6 months in 9 cases. Results Focal lesions were found in 11 cases, in which the deep nuclei were involved in one case and the white matter was involved in 10. Four patients showed both cerebral cortex and white matter lesions, including cerebellum and brainstem invasion in one patient. No corpus callosum lesions were found. Various degree of brain atrophy was found in all patients. Cortical lesions showed swelling and involved subcortical white matter presented as arc shape or strip-like lesions. Patchy patterns were found in deep white matter. Thin layer shaped lesions were found in the periventricular white matter. Small flake-like lesions were found in the brain stem and the cerebellum. The lesions showed hypointensity on T1WI, equal or high signal on T2WI. T2WI FLAIR showed equal or high signal;DWI in the cortex and subcortical white matter lesions showed iso-or high signal, while other lesions were isointense. Eight cases acquired clinical relief in short term without obvious improvement on MRI image. Both clinical symptoms and imaging findings improved in 6 cases. One case showed clinical relief but progression on MRI. Conclusions MRI is an effective way to find immunosuppressive drugs-related encephalopathy in children with aplastic anemia after allogeneic hematopoietic stem cell transplantation. It can help the diagnosis and provide the information for clinical treatment. Key words: Anemia, aplastic; Hematopoietic stem cell transplantation; Magnetic resonance imaging