Acute fulminant cerebellitis in children: a case series and literature review on diagnostic challenges and management strategies.

Background: Acute cerebellitis (AC) in children is often benign; however, a fulminant variant featuring rapid cerebellar edema, hydrocephalus, and brainstem compression can be life-threatening. Case summary: We present a three-case series of pediatric patients with fulminant cerebellitis. The first patient, a 12-year-old female, experienced rapid neurological decline despite initial corticosteroid therapy and underwent emergent posterior fossa decompression, resulting in full neurological recovery. The second patient, a 2-year-old female, presented with obstructive hydrocephalus, initially misdiagnosed as a posterior fossa neoplasm; despite high-dose corticosteroids and delayed external ventricular drainage (EVD), she progressed to brainstem failure and succumbed. The third patient, a 10-year-old male, was treated with urgent EVD insertion, high-dose corticosteroids, and intensive care monitoring, achieving rapid clinical improvement and complete recovery. Conclusion: Fulminant AC in children, although rare, carries a high risk of morbidity and mortality. Prompt recognition and aggressive management, including high-dose corticosteroids, cerebrospinal fluid diversion, and timely posterior fossa decompression when needed, can substantially reduce morbidity and mortality in fulminant cerebellitis.