Mounting evidence suggests the coronavirus might affect more than just the lungs. Delirium, brain inflammation, stroke, and nerve damage are just some of the possible neurological complications of COVID-19, according to a study published last week on 8 July in the journal Brain (1).
The team of neurologists at University College London (UCL) reported neurological symptoms of 43 people between the ages of 16 to 85 with confirmed or suspected COVID-19 infections treated at the National Hospital for Neurology and Neurosurgery in London.
Of the 43 patients examined, the researchers found ten cases of transient encephalopathies (temporary brain dysfunction) with delirium or psychosis, 12 cases of brain inflammation, and eight cases of strokes. A further eight cases of nerve damage were identified, mainly Guillain-Barré syndrome, a type of nerve damage that typically occurs after a respiratory or gastrointestinal infection and can cause paralysis.
The prevalence of a rare and potentially fatal inflammatory condition called acute disseminated encephalomyelitis (ADEM) also seems to be increasing due to the pandemic – from one case per month to one per week during the study period. The condition is typically triggered by a viral infection in children. Eight of the 12 cases of brain inflammation were diagnosed with ADEM.
In a statement, senior author Dr Michael Zandi said: “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 – perhaps similar to the encephalitis lethargica outbreak in the 1920s and 1930s after the 1918 influenza pandemic – remains to be seen”.
The existing clinical evidence suggests these complications are not caused by the virus itself – detected in the cerebrospinal brain fluid of any of the patients tested – but rather brain inflammation is likely caused by an immune response to the infection.
Co-author Dr Rachel Brown added: “Our study advances understanding of the different ways in which Covid-19 can affect the brain, which will be paramount in the collective effort to support and manage patients in their treatment and recovery”.
The report adds to a growing body of research indicating that SARS-CoV-2 may be linked to potentially fatal brain damage and neurological problems. But the entire spectrum of brain diseases and long-lasting side effects caused by the coronavirus may not yet have been recorded, Zandi says.
The virus is unusual because it can cause severe brain damage even in those with mild symptoms. A patient’s lungs could be fine, but their brain may not be, which means the damage could go undetected until it’s too late. No other virus has been shown to attack the brain in the same way and neurologists fear COVID-19 could cause subtle brain damage in some patients, which only become apparent in years to come.
“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”, said co-author Dr Ross Paterson.
“Doctors needs to be aware of possible neurological effects, as early diagnosis can improve patient outcomes. People recovering from the virus should seek professional health advice if they experience neurological symptoms”.
(1) Paterson, R.W. et al. The emerging spectrum of COVID-19 neurology: clinical, radiological and laboratory findings. Brain (2020). DOI: 10.1093/brain/awaa240