Pediatric Hospital Medicine Fellow Akron Children's Hospital Akron, Ohio, United States
Background: The role of Magnetic Resonance Imaging (MRI) in evaluation and management of patients with La Crosse Virus (LACV), a well-known cause of pediatric meningoencephalitis and a public health issue in the mid-western US, is not clear. Published data on MRI abnormalities is mostly limited to case reports or studies with other primary focus. The findings thus far have varied from normal appearance to changes in frontotemporal regions mimicking Herpes Simplex Virus (HSV) encephalitis. Objective: This study aims to describe the MRI abnormalities of a large cohort of patients with LACV encephalitis. We hypothesize that abnormal MRIs correlate with greater severity of illness. In addition, we seek to review if MRI abnormalities in LACV have a distinctive pattern. As Herpes encephalitis remains in the differential for patients presenting with LACV encephalitis, we felt it would be valuable to know how often LACV mimics HSV encephalitis on MRI. Our study is the first one to systematically review MRI changes in patients with LACV. Design/Methods: This single center retrospective cohort study evaluates children aged 0 to 18 years of age admitted to our institution with LACV infection from August 2013 to September 2023. This study was approved by the hospital’s Institutional Review Board. We utilized our organizations laboratory database to obtain charts of patients who had been tested for LACV. Individual charts were manually reviewed and LACV encephalitis diagnosis was confirmed by serum detection of Immunoglobulin G antibody (IgG Ab) to LACV of at least 1:16 or an increase in the serum titer of IgG Ab to at least four times its value at the time of admission. A neuro radiologist individually reviewed every MRI image in this cohort. All variables were compared between groups of patients with no MRI, normal MRI or abnormal MRI using a two-sided test with a p value of < 0.05 chosen as statistically significant. All statistical analyses were performed using the SAS 9.4 (Cary, NC, USA) software.
