Erythema multiforme-like lesions in children and COVID-19

Abstract

During examination of cases of chilblains in children and adolescents, we identified four patients who also showed skin lesions similar to erythema multiforme (EM). They had no other known triggers for EM. One of them had a positive PCR for SARS-CoV-2, while the other three were negative. Skin biopsies from two patients showed features not typical of EM, such as deep perivascular and perieccrine infiltrate and absence of necrosis of keratinocytes. Immunohistochemistry for SARS-CoV/SARS-CoV-2 spike protein showed granular positivity in endothelial cells and epithelial cells of eccrine glands in both biopsies. All patients had an excellent outcome, and had minimal or no systemic symptoms. The coincidence of EM, a condition commonly related to viruses, and chilblains in the setting of COVID-19, and the positivity for SARS-CoV/SARS-CoV-2 spike protein by immunohistochemistry strongly suggest a link between EM-like lesions and SARS-CoV-2.

Keywords: COVID-19; SARS-CoV-2; chilblains; erythema multiforme; exanthem; pernio; skin; viral diseases.

FIGURE 1

A and B, Case 1.Large, confluent targets and targetoid lesions on the hands and elbows, with some small hemorrhagic crusts

FIGURE 2

A and B, Case 2. Targetoid lesions on dorsum of hands and knees. C, Case 3. Targetoid lesions on the hands and forearms. Also, note pernio‐like erythema on the fingertips

FIGURE 3

A‐C, Skin biopsy from the lateral foot in Case 1. A, Interface dermatitis with superficial and deep perivascular lymphocytic inflammation (H&E, original magnification 20×). B, Moderate exocytosis with vacuolar changes and spongiosis. No necrotic keratinocytes are seen. (H&E stain, original magnification 100×). C, Deep extension of the inflammatory infiltrate involving eccrine glands (H&E stain, original magnification 40×). D‐F, Skin biopsy from the knee in Case 2. A, Superficial and deep perivascular inflammation and vascular ectasia (H&E stain, original magnification 20×). B, Mild exocytosis, vacuolar changes, and spongiosis. No necrotic keratinocytes are seen. (H&E stain, original magnification 40×). C, A mid dermal vessel showing transmural lymphocytic infiltration and plump endothelial lining (H&E stain, original magnification 400×)

FIGURE 4

Case 1. Cytoplasmic granular positivity for SARS‐CoV/SARS‐CoV‐2 spike protein in endothelial cells of the upper dermis vessels (A and B), and epithelial cells of the acrosyringia (C) (original magnification A: 100×; B: 200×; C:400×)