PT  - JOURNAL ARTICLE
AU  - P. Malik
AU  - L. Antonini
AU  - P. Mannam
AU  - F.N. Aboobacker
AU  - A. Merve
AU  - K. Gilmour
AU  - K. Rao
AU  - S. Kumar
AU  - S.E. Mani
AU  - D. Eleftheriou
AU  - A. Rao
AU  - C. Hemingway
AU  - S.V. Sudhakar
AU  - J. Bartram
AU  - K. Mankad
TI  - MRI Patterns in Pediatric CNS Hemophagocytic Lymphohistiocytosis
AID  - 10.3174/ajnr.A7292
DP  - 2021 Oct 07
TA  - American Journal of Neuroradiology
4099  - http://www.ajnr.org/content/early/2021/10/07/ajnr.A7292.short
4100  - http://www.ajnr.org/content/early/2021/10/07/ajnr.A7292.full
AB  - BACKGROUND AND PURPOSE: Neuroimaging has an important role in detecting CNS involvement in children with systemic or CNS isolated hemophagocytic lymphohistiocytosis. We characterized a cohort of pediatric patients with CNS hemophagocytic lymphohistiocytosis focusing on neuroradiologic features and assessed whether distinct MR imaging patterns and genotype correlations can be recognized.MATERIALS AND METHODS: We retrospectively enrolled consecutive pediatric patients diagnosed with hemophagocytic lymphohistiocytosis with CNS involvement treated at 2 pediatric neurology centers between 2010 and 2018. Clinical and MR imaging data were analyzed.RESULTS: Fifty-seven children (40 primary, 70%) with a median age of 36 months (interquartile range, 5.5–80.8 months) were included. One hundred twenty-three MR imaging studies were assessed, and 2 broad imaging patterns were identified. Pattern 1 (significant parenchymal disease, 32/57, 56%) was seen in older children (P = .004) with worse clinical profiles. It had 3 onset subpatterns: multifocal white matter lesions (21/32, 66%), brainstem predominant disease (5, 15%), and cerebellitis (6, 19%). All patients with the brainstem pattern failed to meet the radiologic criteria for chronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroids. An attenuated imaging phenotype (pattern 2) was seen in 25 patients (44%, 30 studies) and was associated with younger age.CONCLUSIONS: Distinct MR imaging patterns correlating with clinical phenotypes and possible genetic underpinnings were recognized in this cohort of pediatric CNS hemophagocytic lymphohistiocytosis. Disruptive mutations and missense mutations with absent protein expression correlate with a younger onset age. Children with brainstem and cerebellitis patterns and a negative etiologic work-up require directed assessment for CNS hemophagocytic lymphohistiocytosis.CLIPPERSchronic lymphocytic inflammation with pontine perivascular enhancement responsive to steroidsHLHhemophagocytic lymphohistiocytosisHSCThematopoietic stem cell transplant