The brain and spinal cord are typically grossly normal, but vascular congestion and discolouration of the CNS may be seen. Histologically the entire brain is affected by nonseptic mononuclear cell and neutrophilic inflammation. Severe lesions are noted in the cerebral cortex, thalamus and hypothalamus. Mononuclear meningitis, neuronal degeneration, gliosis and perivascular cuffing with mononuclear cell and neutrophilic infiltration are evident. Immunohistochemistry can be diagnostic. Liquefactive necrosis and haemorrhage of the cerebral cortex, atrophy of the pancreatic acinar cells and hyperplasia of the pancreatic duct cells commonly occur with VEE. | The brain and spinal cord are typically grossly normal, but vascular congestion and discolouration of the CNS may be seen. Histologically the entire brain is affected by nonseptic mononuclear cell and neutrophilic inflammation. Severe lesions are noted in the cerebral cortex, thalamus and hypothalamus. Mononuclear meningitis, neuronal degeneration, gliosis and perivascular cuffing with mononuclear cell and neutrophilic infiltration are evident. Immunohistochemistry can be diagnostic. Liquefactive necrosis and haemorrhage of the cerebral cortex, atrophy of the pancreatic acinar cells and hyperplasia of the pancreatic duct cells commonly occur with VEE. |