Q&A: Early diagnosis critical in treating encephalitis due to COVID-19, other causes
Feb. 22 marks World Encephalitis Day, a day of global awareness started by the Encephalitis Society for individuals “who have been directly or indirectly affected by encephalitis,” which now includes patients with COVID-19.
Healio Neurology spoke with Omar K. Siddiqi, MD, MPH, a member of the Encephalitis Society’s scientific advisory panel, about the current state of encephalitis management. Siddiqi, an assistant professor of neurology at Harvard Medical School, a visiting lecturer at the University of Zambia School of Medicine and director of the global neurology program at Beth Israel Deaconess Medical Center in Boston, said that — while there have been advances in encephalitis treatment — unmet needs remain.
Healio Neurology: How is encephalitis related to COVID-19 different from other forms of the disease?
Siddiqi: We are still learning about all the neurological complications of COVID-19. Encephalitis appears to occur in multiple ways. There have been case reports of SARS-CoV-2 detection within the spinal fluid and patients presenting with an inflammatory syndrome of the brain. COVID-19 is associated with a high state of inflammation throughout the body. This also adversely affects the brain. There is speculation that the blood vessels that supply blood to the brain become inflamed and result in brain injury in terms of stroke and secondary tissue dysfunction. There also may be inflammation that causes secondary damage to the brain as the immune system fights the virus and there is cross-reactivity to the brain itself.
Healio Neurology: Have there been any recent breakthroughs in treating encephalitis?
Siddiqi: The use of technology called metagenomics next-generation sequencing has allowed for the detection of infectious causes of encephalitis that were previously not considered. We also are recognizing a new form of autoimmune encephalitis that was previously not recognized. Being able to reliably distinguish between infectious and autoimmune encephalitis even a decade ago was extremely difficult; this is important because the treatment will differ greatly between the two. One requires the use of antimicrobial medication while the other will rely on immunomodulatory medication. With the ability to more accurately diagnose the cause of encephalitis, patients receive the appropriate treatment and have a better chance at recovery.
Healio Neurology: What unmet needs remain?
Siddiqi: Some of the diagnostic tests can take time to accurately diagnose encephalitis. There is a saying in the stroke world that time is brain; I would say the same is true for encephalitis. The longer the diagnosis is delayed, the more vulnerable the brain is to further injury. We would like to have prompt point-of-care diagnostics that can give doctors and patients the cause of encephalitis quickly.
We can also always benefit from more targeted treatments. For some forms of viral encephalitis, we can only provide supportive care because we do not have a drug that can actively reduce viral replication. There are still a number of unmet needs.