Longitudinal Functional and Neuropsychological Outcomes Five Years After Neuroinvasive La Crosse Virus Exposure: A Case Report

Research Objectives: To describe functional recovery and neuropsychological outcome following La Crosse Encephalitis which is a rare neuroinvasive arbovirus associated with chronic cognitive and behavioral deficits

Design: Observational single-case study with outcomes were measured during acute rehabilitation and again at 4.75 years post-infection.

Setting: An inpatient neurorehabilitation unit in a tertiary teaching hospital.

Participants: A 21-year-old male with Glasgow Coma Score = 6 (e2,v2,m2) upon acute hospital admission. Neuroimaging four days after admission revealed restricted diffusion and hyperintensities bilaterally in the thalami, mesial temporal lobes, pons, and subcortical white matter. He progressed to Rancho Level 5 and at 10 weeks was transferred to an acute neurorehabilitation unit.

Interventions: He received physical, occupational, and speech therapy throughout his 54-week rehabilitation length of stay.

Main Outcome Measures: Functional Independence Measure (FIM); A comprehensive neuropsychological battery.

Results: The Marine demonstrated functional improvement during rehabilitation hospitalization (FIM Motor Admission=12, Discharge=53; FIM Cognitive Admission=6, Discharge=21) and additional improvement when reassessed at 5 years post-infection (FIM Motor=70; FIM Cognitive=23). Although he remained cognitive impaired at follow up, neuropsychological improvement was observed in attention, memory, and executive functions.

Conclusions: This case highlights long-term functional and neuropsychological improvement following rehabilitation hospitalization. Although rare, La Crosse encephalitis results in profound disability that is responsive to rehabilitation interventions.

Author(s) Disclosures: This material is the result of work supported with resources and the use of facilities at the James A. Haley Veterans’ Hospital. The views, opinions, and/or findings contained in this article are those of the authors and should not be construed as an official Department of Defense position or any other federal agency, policy, or decision unless so designated by other official documentation. The authors declare no financial disclosures and no conflicts of interest.