Acute Hemorrhagic Leukoencephalitis with Proof of Activation of the Complement System and Eculizumab Therapy

Introduction: Acute hemorrhagic leukoencephalitis (AHLE) is a progressive disease which is characterized by an inflammatory, diffuse hemorrhagic demyelination of the central nervous system. It is associated with a high morbidity and mortality.

Patient: A 14-year-old boy presented with acute headache and hemiparesthesia of the right face. On the initial neurological examination, the patient was drowsy but still arousable and showed a vertical gaze palsy. During the following 2 days, he developed a left-sided hemiparesis, and became stuporous. A cranial MRI revealed bilateral laminar, diffuse, and hyperintensive lesions of the cerebellum, basal ganglia, and brainstem in terms of a progressive inflammation. Because of suspected autoimmune genesis of the encephalitis (negative microbiological and viral results), the patient received treatment with methylprednisolone, intravenous immunoglobulin, and plasma exchange. This therapy did not lead to a clinical improvement.

Result: A biopsy of the brain showed typical changes associated with an AHLE. An activation of the complement system in blood and also in the brain biopsy (C4d-immune positivity in the white substance of the brain) could be proved. Eleven days after onset of the symptoms we started an off-label use of eculizumab. During the longtime therapy a distinct improvement of the clinical and neurological symptoms could be observed.

Conclusion: Because of its rarity and very poor prognosis the diagnosis and treatment of AHLE is challenging. In our case, we were able to prove an activation of the complement system as a possible causative mechanism. Therefore the experimental use of eculizumab might be a therapeutic option.