Paraneoplastic Encephalitis

Paraneoplastic encephalitis is an inflammatory brain condition related to cancer. It is usually immune-mediated and often associated with antibodies against intracellular neuronal proteins. Manifestations can include limbic, brainstem encephalitis, or widespread neuraxis involvement. It frequently associates with certain autoantibodies and various types of cancer. Symptoms typically include amnesia, confusion, or seizures.

Overview of Paraneoplastic Encephalitis

Paraneoplastic encephalitis is an inflammatory condition affecting the brain and is cancer-related. It may manifest as limbic, brainstem encephalitis, or be part of widespread involvement of the neuraxis.

Associated Antibodies and Tumors

It often associates with anti-Hu antibodies, anti-Ma2 antibodies, antibodies to glutamic acid decarboxylase (GAD), or CRMP5 antibodies. Common tumor types include small cell lung cancer, testicular malignancy, breast cancer, gastrointestinal malignancies, neuroblastoma, and ovarian cancer.

Treatment with Immunotherapy and Tumor Management

Prompt treatment of the tumor and early initiation of immunotherapy are crucial. Immunotherapy agents include glucocorticoids, IVIG, or plasma exchange. Cyclophosphamide or rituximab may be considered if there's no response.

Dosage Adjustments and Precautions

Dosage adjustments for cyclophosphamide and rituximab should be based on neutrophil and platelet counts. Premedication and monitoring for progressive multifocal leucoencephalopathy are important for patients on rituximab.

Seizure Management

Seizures should be treated aggressively with antiseizure medications during the acute illness, including lorazepam, diazepam, levetiracetam, or fosphenytoin. Long-term antiseizure drug therapy is usually not required.

References

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