Abstract
In the current pandemic with SARS-CoV-2, children can present with severe acute respiratory infection, qualifying as COVID-19 according to published guidelines. However other etiologies should not be overlooked. We present a case of a 10-year old boy with Down syndrome, who presented with fever and respiratory failure. A CT scan of the lungs showed lesions very suggestive of COVID-19. He was admitted to an intensive care unit because of deep hypoxemia requiring high flow nasal oxygen. Polymerase chain reaction on nasopharyngeal swabs was repeatedly negative for SARS-CoV-2 but positive for Mycoplasma pneumoniae.