- Using an international registry, researchers at Massachusetts General Hospital evaluated the duration of dermatological signs and symptoms of COVID-19 in 234 patients, of whom 96 had laboratory-confirmed disease
- Pernio, also known as "covid toes," occurred in 103 patients overall and generally lasted a median of 15 days
- Seven of 103 patients with pernio (6.8%) had symptoms for more than 60 days, a recently accepted definition of "long-haulers"
- Urticarial and morbilliform eruptions were relatively short-lived (median duration four and seven days, respectively, in laboratory-confirmed COVID-19)
"Long-haulers" are COVID-19 patients with symptoms that persist 60 days after they first test positive, and this affects 66% to 87% of all patients. In The Lancet Infectious Diseases, Esther E. Freeman, MD, PhD, director of Global Health Dermatology at Massachusetts General Hospital and associate professor at Harvard Medical School, Devon E. McMahon, MD candidate, and colleagues report for the first time that dermatologic manifestations of COVID-19 can be similarly prolonged.
In April 2020, working with the International League of Dermatological Societies and the American Academy of Dermatology, the researchers established an international registry for health care providers to report COVID-19 dermatologic signs and symptoms.
Overall Duration of Signs/Symptoms
Between April 8 and October 8, 2020, clinicians from 41 countries reported 1,030 cases of COVID-19 with dermatologic manifestations, of which 234 cases had information on the duration of illness, including 96 laboratory-confirmed cases—the largest published dataset on the duration of skin symptoms after COVID-19. The median duration of signs/symptoms was:
- 13 days for all patients
- 7 days for patients with laboratory-confirmed disease
Duration of Covid Toes
Pernio, also known as "covid toes," occurred in 103 patients overall and 12 of the patients with laboratory-confirmed disease. Pernio lasted a median of 15 days overall, and 12 days in laboratory-confirmed cases.
In seven (6.8%) of the 103 patients, pernio lasted for more than 60 days. Two of those patients had laboratory-confirmed COVID-19.
Duration of Other Signs/Symptoms
In patients with laboratory-confirmed COVID-19:
- Morbilliform eruptions (n=19) lasted a median of 7 days
- Urticaria (n=19) lasted a median of 4 days; the maximum duration was 28 days
- Papulosquamous eruptions (n=9) lasted a median of 20 days; one case lasted 70 days
Tip of the Iceberg
Requesting case updates may have biased the result towards the inclusion of cases with shorter duration of dermatological symptoms. Therefore, the duration of dermatological manifestations reported here probably underestimates both the average duration and the number of long-hauler patients.
"What's interesting about this study is that it demonstrates that patients who had relatively mild COVID-19 to begin with, can demonstrate long-lasting effects of the infection, which we see in the skin," says Dr. Freeman. "This raises questions about persistent inflammation in the body."
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