INTRODUCTION
Encephalitis is characterized by brain dysfunction due to inflammation
of the brain parenchyma and is associated with significant morbidity and
mortality. Despite significant advances in diagnostic methods, the
etiology remains unknown in about 60% of cases.1-3
Immunocompromised patients with encephalitis pose unique diagnostic and
therapeutic challenges. They are more likely to have atypical
presentations from common pathogens and are at higher risk of infections
by novel agents.4
Classical human astroviruses (HAstV) are gastrointestinal pathogens
responsible for approximately 10% cases of acute, non-bacterial
gastroenteritis in children.5-7 Recently discovered,
divergent strains of HAstV, MLB and VA1, also cause self-limited
diarrheal illnesses.6,8 However, HAstVs have also been
reported to cause fatal encephalitis, primarily in immunocompromised
hosts. To date, 10 cases of HAstV central nervous system (CNS) infection
have been reported.9-17 The most frequently identified
strain has been VA1.9,11-14 We report 2 cases of
HAsV-VA1 encephalitis in children with cancer at our institution and
perform a literature review of previously published cases.