Coloured 2D magnetic resonance imaging (MRI) and 3D computed tomography (CT) scans of the brain of a patient with active covid-19 and multisystem inflammatory syndrome in adults (MIS-A). Lesions (pink) can be seen in the splenium of the corpus callosum (lower centre) and in the cerebral white matter. MIS-A is a rare but severe complication of covid-19 infection that usually presents 4 to 6 weeks after infection. It causes inflammation in multiple organ systems including the brain, heart, lungs and gastrointestinal system, so symptoms can be wide ranging. MIS-A can be fatal especially if not diagnosed and treated early enough.