Abnormalities on brain MR images during the course of familial haemophagocytic lymphohistocytosis in a child. A case report

Purpose. To describe and report the neuroradiological findings and clinical features in a patient with familial haemophagocytic lymphohistocytosis (FH L), a rare hereditary immune dysregulation in early childhood characterised by multisystem involvement, including in approximately 30% of cases also t he central nervous system (CNS). Material and Methods. Serial brain MR examinations were carried out in a 4. 5-year-old boy with FHL, finally complicated with Epstein-Barr virus (EBV)d riven posttransplantation lymphoma. Results. Multiple brain MR examinations before and after contrast enhanceme nt showed discrete perivascular non-enhancing areas of high signal intensit y on T2 images, and later also an enhancing lesion in the right caudate nuc leus. Conclusion. FHL should be included in the differential diagnosis of patchy white matter abnormalities in young patients. EBV-driven post-transplantati on lymphoma, which may present as meningial and/or parenchymal CNS infiltra tion, is a differential diagnostic problem.