Acral purpuric lesions associated with coagulation disorders during the COVID-19 pandemic.

Dear Editor,

Different cutaneous manifestations have been described during the COVID‐19 pandemic. These include acral erythematous‐purpuric lesions reminiscent of perniosis, which are present in 19% of cases with suspected COVID‐19 skin lesions. These patients usually have no clinical symptoms related to COVID‐19, and the results of their diagnostic tests for SARS‐CoV‐2 are negative. The presence of other cutaneous manifestations, such as purpuric‐petechial eruptions, has been described being distributed in acral areas.

In contrast, alterations in coagulation are frequent in patients with COVID‐19. An elevated D‐dimer level, prolonged prothrombin time, decreased prothrombin activity, and elevated fibrinogen levels are some of such alterations.

An 18‐year‐old male came to the emergency department presenting with purpuric lesions on the inner side and back of his feet, which developed over the course of 5 days (Fig. 1a). He also complained of headache and general malaise. No new drugs were given. Three weeks ago, he presented with a catarrhal disorder, which was associated with a papulovesicular rash similar to varicella (Fig. 1b).

Figure 1

Clinical images. (a) Acral purpuric‐petechial eruption located on both feet. (b) Papulovesicular eruption distributed on the trunk. Erythematous papules and ruptured vesicles are seen

Analytical tests showed a prolongation of the prothrombin time (15.9 s), a decrease in prothrombin activity (68%), a slightly elevated INR‐TP (1.29), an elevated D‐dimer level (674 µg/l), an elevated fibrinogen level (511 mg/dl), mild plateletpenia (143 ml/mm3), a relative monocytosis (15.5%) without associated leukocytosis, a high erythrocyte sedimentation rate (22 mm), and a C‐reactive protein of 8.11 mg/l. The urinalysis showed no alterations. The autoimmunity study included cryoglobulins, cold agglutinins, rheumatoid factor, antinuclear antibodies, and complements and came back negative.

Serological tests for Epstein–Barr virus, cytomegalovirus, parvovirus B19, Mycoplasma pneumoniae, HIV, and hepatitis B and C were carried out, as well as RT‐PCR for enterovirus, which all came back negative. The results of the nasopharyngeal RT‐PCR and SARS‐CoV‐2‐specific IgA + IgM and IgG antibody serologies were also negative. Two weeks later, the serological tests were repeated and came back negative once again.

The skin biopsy performed showed a perivascular lymphoid infiltrate in the dermis, both superficial and deep. The vessels surrounded by the lymphoid infiltrate had plump endothelial cells, and fibrin was focally present. In some areas, the lymphoid infiltrate was so dense that it obscured the vessel wall (Fig. 2). Direct immunofluorescence was negative, including antibody–fluorophore conjugates to IgG, IgM, IgA, complement proteins C1q, C3, and C4c, and fibrinogen. This histology is similar to that previously reported.

Figure 2

Histopathological findings. (a) Skin biopsy shows a superficial and deep perivascular lymphoid infiltrate (H&E, ×2). (b) The endothelium surrounded and admixed with the lymphocytic infiltrate shows enlarged nuclei. Hematic extravasation and fibrin are focally present (H&E, ×20)

We present a case of acral purpura in which the histology showed a lymphocytic vasculitis process, with significant vascular damage and fibrin presence. These lesions were associated with alterations in coagulation tests typically reported in patients with COVID‐19, such as prolonged prothrombin time and elevated D‐dimer levels. However, similar to other studies on acral lesions during the COVID‐19 pandemic, we were unable to identify the presence of acute or past infection, , despite the fact that the patient was in a risky epidemiological environment and previously presented with respiratory infection and a varicella‐like exanthem described as specific to COVID‐19.

These findings may indicate that they are skin lesions corresponding to minimal forms of infection or past infection that cannot be identified with current detection techniques.

In conclusion, we are witnessing an emerging epidemiological context of acral purpuric lesions during the COVID‐19 pandemic and, in this case, associated typical manifestations of SARS‐CoV‐2 infection, such as alterations in coagulation tests, the papulovesicular exanthem, and the upper respiratory infection.