A case of acute encephalophathy with residual neurological sequelae induced by immunoglobulin A vasculitis.

• Immunoglobulin A vasculitis (IgAV) induces acute encephalopathy. • Neurological sequelae can be caused by IgAV, even extremely rare. • MRI showed unusual biphasic features and reduced cerebral blood flow. • Cerebrospinal fluid interleukin-6 level was markedly elevated. Immunoglobulin A vasculitis (IgAV) occasionally induces central nervous system (CNS) involvement, which is usually transient with no sequelae except for hemorrhagic stroke. It is thought to be useful to measure serum and cerebrospinal fluid (CSF) cytokine levels for better understanding the pathological condition in encephalopathy, but there have been no reports in acute encephalopathy with IgAV. We describe an 8-year-old boy with IgAV who had neurological sequelae after complication of acute encephalopathy, focusing on the cytokine profiles and unique biphasic findings of magnetic resonance imaging. He presented with status epilepticus and mildly intensified area in the occipital lobe on the fluid-attenuated inversion recovery view. Arterial spin labeling (ASL) revealed the reduction of cerebral blood flow in the left hemisphere. On day 5 of illness, these abnormal findings disappeared, but delayed hyperintensity lesions on diffusion-weighted images newly emerged. Furthermore, CSF interleukin (IL)-6 levels markedly increased without elevated levels of IL-10 during the acute phase of disease. He suffered from long-lasting hemiparesis and intellectual impairment. In conclusion, acute encephalopathy with IgAV could cause neurological sequelae by prolonged seizure, and elevated IL-6 in CSF and laterality of cerebral blood flow in ASL might be useful to predict the prognosis of CNS dysfunction of IgAV. [ABSTRACT FROM AUTHOR]