New York, Oct 29 (IANS): In a major study, researchers have found that some patients with Covid-19 have persistent skin-related symptoms long after their initial infection has cleared.

The findings, presented at the 29th Congress of the European Academy of Dermatology and Venereology, point to another burden experienced by so-called "long haulers" who get better but don't seem to fully recover from Covid-19.

"Our findings reveal a previously unreported subset of patients with long-standing skin symptoms from Covid-19, in particular those with Covid toes," said study author Esther E Freeman from Massachusetts General Hospital in the US.

"This data adds to our knowledge about the long-term effects of Covid-19 in different organ systems. The skin is potentially a visible window into inflammation that could be going on in the body," Freeman added.

For the analysis, researchers established an international registry for Covid-19 skin manifestations in April 2020, in collaboration with the International League of Dermatological Societies and the American Academy of Dermatology.

Clinicians were contacted in June and August to update Covid-19 laboratory test results and the duration of patients' Covid-19 skin symptoms.

The team defined long haulers as anyone with skin symptoms of Covid-19 that persisted for at least 60 days.

The team evaluated almost 1,000 cases of patients with skin manifestations of Covid-19.

Among 224 total suspected cases and 90 laboratory-confirmed cases of Covid-19 from 39 countries with information on symptom duration, the median duration of symptoms was 12 days.

According to the study, rash-like morbilliform and urticarial eruptions lasted a median of seven days and four days, respectively, for patients with lab-confirmed Covid-19, with a maximum duration of 28 days.

Papulosquamous eruptions, which are scaly papules and plaques, lasted a median of 20 days in lab-confirmed cases, with one confirmed long hauler eruption lasting 70 days.

The findings revealed Pernio/chilblains, or redness and swelling of the feet and hands, commonly known as "Covid toes," lasted a median of 15 days in patients with suspected Covid-19 and 10 days in lab-confirmed cases.

Notably, six patients with pernio/chilblains were long haulers with toe symptoms lasting at least 60 days, with two lab-confirmed patients with Covid- toes lasting longer than 130 days.

"We encourage clinicians taking care of patients with Covid-19 to ask about and evaluate any skin symptoms," the study authors wrote.