Autoimmune Encephalitis in Kathmandu — When the Immune System Attacks the Brain

Autoimmune encephalitis is a group of conditions where the immune system mistakenly attacks components of the brain, causing inflammation and neurological dysfunction. Once considered rare, improved diagnostic testing has revealed that autoimmune encephalitis is more common than previously thought and is an important treatable cause of encephalitis and cognitive decline.

Autoimmune encephalitis can be triggered by infections (paraneoplastic encephalitis associated with cancer, or post-infectious encephalitis after viral infections), tumors, or occur without an identifiable trigger. Different antibodies target different brain proteins, producing distinct clinical syndromes. For example, anti-NMDA receptor encephalitis typically affects young adults and causes psychiatric symptoms, memory loss, seizures, and movement disorders. Anti-LGI1 encephalitis often presents with limbic encephalitis (memory loss, seizures) and faciobrachial dystonic seizures.

Dr. Jitendra Prasad Yadav — consultant neurologist & headache specialist at Kathmandu Neurology Clinic & Cognitive Center provides evidence-based evaluation for epilepsy.

Symptoms develop over days to weeks and typically involve multiple domains. Psychiatric symptoms are common and may include psychosis, agitation, anxiety, or personality change. Cognitive impairment affects memory, attention, and executive function. Seizures occur in many patients and may be the presenting symptom. Movement disorders including dystonia, chorea, or parkinsonism may develop. Sleep disturbances and autonomic dysfunction can also occur.

Diagnosis requires a high index of suspicion because symptoms often mimic psychiatric illness or infectious encephalitis. Brain MRI may show inflammation in the mesial temporal lobes (limbic encephalitis) or may be normal. EEG frequently shows slowing or epileptiform activity. The definitive test is antibody testing in cerebrospinal fluid and serum, which identifies the specific autoimmune target. Cancer screening (CT chest/abdomen/pelvis, mammography, testicular ultrasound) is essential when paraneoplastic encephalitis is suspected, as identifying and treating the underlying tumor is critical for neurological recovery.

Treatment involves immunotherapy to suppress the abnormal immune response. First-line treatment typically includes corticosteroids, intravenous immunoglobulin (IVIG), or plasma exchange (plasmapheresis). Many patients require second-line immunotherapy with rituximab, cyclophosphamide, or mycophenolate for sustained remission. When a tumor is identified, oncology treatment (surgery, chemotherapy, radiation) is also essential.

Recovery varies significantly. Some patients recover completely with prompt treatment, while others have persistent neurological deficits. Anti-NMDA receptor encephalitis often has a good prognosis with appropriate treatment, though recovery may take months. Early diagnosis and aggressive immunotherapy improve outcomes.

At Kathmandu Neurology Clinic & Cognitive Center, Dr. Jitendra Prasad Yadav (NMC 8029) evaluates suspected autoimmune encephalitis and coordinates with rheumatology, oncology, and infectious disease specialists when needed. The clinic arranges antibody testing, MRI, EEG, and cancer screening as indicated.

This article is educational and does not replace individual medical advice.

**Frequently Asked Questions**

Q: What causes autoimmune encephalitis? A: Autoimmune encephalitis occurs when the immune system produces antibodies that attack brain proteins. Triggers include tumors (paraneoplastic), infections, or it may occur without an identifiable trigger. Genetic factors may also play a role in susceptibility.

Q: Is autoimmune encephalitis curable? A: Many patients with autoimmune encephalitis recover significantly with immunotherapy, particularly when treatment is started early. Some patients achieve complete remission, while others have persistent deficits. Recovery can take months and requires sustained treatment.

Q: How is autoimmune encephalitis different from infectious encephalitis? A: Infectious encephalitis is caused by direct infection of the brain by viruses, bacteria, or other pathogens. Autoimmune encephalitis is caused by the immune system attacking the brain, often without an infection present. The treatment approaches differ — antibiotics/antivirals for infectious causes versus immunotherapy for autoimmune causes.

Q: What are the first symptoms of autoimmune encephalitis? A: Early symptoms often include psychiatric changes (psychosis, agitation, personality change), memory loss, confusion, seizures, or headache. Because psychiatric symptoms can be prominent, the condition is sometimes initially mistaken for primary psychiatric illness.

Q: What testing is needed for autoimmune encephalitis? A: Testing includes brain MRI, EEG, lumbar puncture for CSF analysis (including antibody testing), and blood antibody testing. When paraneoplastic encephalitis is suspected, comprehensive cancer screening is also performed to identify an underlying tumor.

Q: Can autoimmune encephalitis recur? A: Yes, autoimmune encephalitis can recur, particularly when an underlying tumor is present or when immunotherapy is stopped too early. Many patients require prolonged immunotherapy to maintain remission. Regular follow-up is important to monitor for relapse.