Non-acral skin manifestations during the COVID-19 epidemic: COVIDSKIN study by the French Society of Dermatology.

Conflict of interest

Dr. Fourati received personal fees from Abbott outside the submitted work. The other authors had nothing to disclose.

Funding source

None.

Dear Editor,

A variety of skin manifestations occurring during the COVID‐19 pandemic have been reported since March 2020. The most reported were chilblain‐like lesions, widespread urticaria, maculopapular eruptions, vesicular eruptions and vascular lesions such as livedo or necrosis. , , Cutaneous manifestations are rare with a frequency estimated around 2% of patients with a biologically confirmed COVID‐19. , , , A national survey, COVIDSKIN study of the French Society of Dermatology, was carried out from March 30 to June 11, 2020, asking hospital and private physicians to report, using a standardized questionnaire, cases of skin manifestations in patients with COVID‐19 clinically suspected. We report skin manifestations excluding acral manifestations, described separately. We aimed to describe the characteristics, the skin manifestations and the biological diagnostic tests' results of suspected COVID‐19 patients.

Among the 492 collected cases, after excluding 311 patients with acral manifestations and 65 for whom no COVID‐19 tests were performed, we included 116 patients: 52 had positive COVID‐19 tests (45 positive RT‐PCR, eight positive serology; including one patient positive for both) and were then considered as ‘confirmed COVID‐19 group’ and 64 who had negative tests (15 with negative RT‐PCR and 49 with negative results for both RT‐PCR and serology) but who were clinically suspected, then considered as ‘unconfirmed COVID‐19 group’. The available photographed manifestations were classified by four dermatologists according to Galván Casas et al. (maculopapular eruptions, urticaria, vesicular rash, necrosis/livedo and other eruptions).

The overall median age was 38 [interquartile range (IQR) 28–52]. All the hospitalized patients were in the confirmed group (25/52) except for two patients with negative RT‐PCR. Four patients were died, all from the COVID‐19‐confirmed group. Median time between the first infectious symptoms when present (n = 86) and RT‐PCR was 6 days (IQR 3–13) and median time to serology was 26.5 days (IQR 13–33.3). Median time between the first infectious symptoms and cutaneous manifestations was 7 days (IQR 3–16). Patients' and characteristics and biological tests' are summarized in Table 1.

Table 1

Dermatologic manifestations in patients with confirmed and unconfirmed COVID‐19

Overall population, n = 116	Confirmed COVID‐19 patients, n = 52 n (%)	Unconfirmed COVID‐19 patients, n = 64 n (%)
Age in year, median (IQR)	44.5 (30.3–63.5)	36 (25–44.5)
Male patient	31 (60)	40 (62)
Anosmia/ageusia	21 (41)	10 (16)
At least one symptom	46 (88)	40 (62)
Time between date of first infectious symptoms and:
RT‐PCR in days, median (IQR)	5 (2.25–9)	7.50 (4–26)
Serology in days, median (IQR)	28 (26.5–31)	25 (10–33)
Cutaneous manifestations in days, median (IQR)	7 (4.75–13.8)	8 (0–23)
Deaths	4 (8)	0

Data are presented as n (%) unless otherwise indicated.

Histologically confirmed diagnosis. ‡Deceased patients: maculopapular rashes, n = 2; urticaria, n = 1; purpura/livedo, n = 1.

Confirmed COVID‐19 patients, n = 38

Unconfirmed COVID‐19 patients, n = 33

Pictures of the lesions were available for 71 patients (Fig. 1). The most common manifestation was maculopapular eruption. The frequency and distribution of the types of skin manifestations did not significantly differ between the confirmed and unconfirmed COVID‐19 patients (P = 0.199), as summarized in Table 1, although urticarial eruptions seemed more frequent among confirmed patients. In the confirmed group, the frequency and distribution of the types of manifestations did not differ between hospitalized and non‐hospitalized patients.

Figure 1

Photographs of dermatologic manifestations. (a) Diffuse maculopapular rash, (b) urticaria, (c) livedo.

Previously, two large retrospective series classified respectively 304 COVID‐19 and 126 cases found the following types of non‐acral manifestations' frequencies: 58–61% maculopapular eruptions; 21–24% urticaria; 11–14% vesicular eruptions; and 7–9% livedo/necrosis. , We observed these manifestations in similar proportions, especially among patients with confirmed COVID‐19 (Table 1). We could not exclude the possibility of false negative for some patients, specifically for those who reported anosmia/ageusia and when RT‐PCR was not followed by serological testing, while this probability was low for RT‐PCR and seronegative patients. Indeed, asymptomatic COVID‐19 patients have a similar rate of seroconversion than symptomatic patients and the 58 serologies performed had a sensitivity and specificity above 98% in the timeframe they were performed.

As previously stated, given the dermatological manifestations' heterogeneity, possible differential diagnoses, classification bias and the absence of gold‐standard test to exclude COVID‐19, it was not possible to determine which cutaneous manifestations are directly related or not to the infection. , Further prospective studies with systematic dermatological examination of patients with proven COVID‐19 are needed to establish a formal association between infection and specific cutaneous manifestations.