Doctors have identified a new symptom of COVID-19, caused by the novel coronavirus, informally dubbed “COVID toes.”
The new symptom – a presence of purple or blue lesions on the patient’s feet and toes – is puzzling infectious disease experts.
“They’re typically painful to touch and could have a hot burning sensation,” said Dr. Ebbing Lautenbach, chief of infectious disease at the University of Pennsylvania's School of Medicine.
What doctors say is most interesting about "COVID toes" is that it seems to appear in COVID-19 patients who don’t exhibit any symptoms. Similarly, the loss of taste and smell was also found to be associated with COVID-19 among asymptomatic patients by the American Academy of Otolaryngology – Head and Neck Surgery and ENT UK in late March.
“This is a manifestation that occurs early on in the disease, meaning, you have this first then you progress,” he said. “Sometimes this might be your first clue that they have COVID when they don’t have any other symptoms.”
“COVID toes” in some people can disappear in the course of a week or 10 days, while others progress to respiratory symptoms, he said.
Another interesting phenomenon is that the new symptom seems to appear in more children and young adults than any other age group. Ebbing suggests this may be because children and young adults have better immune systems.
According to the Ebbing, “COVID toes” were first discovered in March by Italian doctors. Once experts were informed of the strange symptom, they began recognizing more and more cases in the U.S.
Experts say there are two running hypotheses on what could cause “COVID toes." One possible explanation, Ebbing said, could be that there is an inflammatory response more localized to a patient’s foot and toes. Or it could be a clotting of blood vessels.
“The short answer is nobody knows,” he said.
Dr. Susan Wilcox, chief of critical care for the emergency department at Massachusetts General Hospital, said another condition could also explain “COVID toes.”
She saw the purple lesions on her most critically ill COVID patients and believed it was purpura fulminans. This occurs when inflammation from a severe infection causes the body to make micro clots in tiny blood vessels located in the toes, fingers and even nose, she explains.
'Almost like an eternity':3 months since US confirmed its first coronavirus case, what have we learned?
Wilcox said this is most common in patients who develop acute respiratory distress syndrome, or ARDS, where the vast majority die of intense, systematic inflammation.
“You get the infection and then your body will release a cascade of inflammation,” she said. “In many ways it’s beneficial, but then sometimes it can either be too much so the inflammation can lead to its own damage.”
Wilcox said she’s also seen this happen in cases of viral pneumonia or a bad flu, so it wasn’t surprising when she saw it in COVID-19 patients.
While experts continue to learn more about the disease and how it relates to “COVID toes,” Ebbing said an abundance of caution and a low bar of suspicion is what will stop the spread of the coronavirus.
Although patients with “COVID toes” are more likely to test negative for COVID-19, as the virus is in its earliest stages, he believes that patients should quarantine at home and monitor closely for developing symptoms.
Follow Adrianna Rodriguez on Twitter: @AdriannaUSAT.