Nine cases in the UK capital are said to have shown signs of “concerning” disseminated encephalomyelitis (Adem) The rare form of brain inflammation involves swelling of the brain and spinal cord LONDON: Specialists in London have linked COVID-19 to a rare form of brain inflammation. Nine cases in the UK capital are said to have shown signs of “concerning” disseminated encephalomyelitis (Adem), which involves swelling of the brain and spinal cord, leading to weakness in the limbs, loss of balance, fatigue and drowsiness. So far, the cases have only occurred in adults with confirmed or suspected COVID-19 infections, and represent the number the UK would expect to see nationally over the course of five months. Adem is usually triggered by a viral infection, causing immune cells to attack the protective coating covering the nervous system. COVID-19 was not detected in the brain or spinal fluid of any of the patients, according to the study, but evidence suggested that brain inflammation had been caused by an immune response to the disease. Adem is not the only disorder linked to COVID-19. A study in the medical journal Brain has so far linked the virus to 43 different cases in the UK, including a brain disorder known as encephalopathy with delirium, which has so far affected 10 patients, and which causes confusion and even psychosis and seizures. “We know from previous viruses that you can get neurological (consequences), so I don’t think we should be terribly surprised, but the range of clinical complications is broad,” said Dr. Ross Paterson of the UCL Queen Square Institute of Neurology, who co-authored the study published in Brain. “To have cases of delirium with psychosis, completely out of proportion with the respiratory virus, is unusual. The cases we are seeing are perhaps just a small snapshot of the severe end of the spectrum,” he added. “Given that the disease has only been around for a matter of months, we might not yet know what long-term damage COVID-19 can cause. Doctors need to be aware of possible neurological effects as early diagnosis can improve patient outcomes.” Patterson’s co-author Dr. Michael Zandi, also of the UCL Queen Square Institute of Neurology, said: “We identified a higher than expected number of people with neurological conditions such as brain inflammation, which did not always correlate with the severity of respiratory symptoms.” Zandi added: “We should be vigilant and look out for these complications in people who have had COVID-19. Whether we will see an epidemic on a large scale of brain damage linked to the pandemic … remains to be seen.”