Mask-induced psoriasis lesions as Köebner phenomenon during COVID-19 pandemic.

Dear Editor,

Universal use of face masks as a means of source control in public places during the COVID‐19 pandemic is advocated by all health agencies. A high degree of compliance will maximize the impact of universal masking in public. Here, we describe a case of ear‐looped mask‐related Köebner phenomenon in a known case of psoriasis at the time of coronavirus disease (COVID‐19) pandemic.

CASE REPORT

A 74‐year‐old male developed mild itchy, well defined erythematous, scaly lesion in the left supra‐auricular are and it was extending to the adjoining scalp area also since the past 4 weeks. Cutaneous examination revealed lesions typical of psoriasis—well defined plaque with silvery white scales (Figure 1). He was a known case of psoriasis with prolonged remission after administration of secukinumab. The present visit was almost after 4 months. He gave history of using ear‐looped mask (Figure 2) since the start of the COVID‐19 pandemic in India since March 2020. He was advised topical corticosteroids and avoidance of use of ear‐looped mask.

FIGURE 1

Well‐defined plaque with silvery white scales

FIGURE 2

Face mask with ear loops

DISCUSSION

The COVID‐19 pandemic forced the exponential use of masks by general population as personal protective equipment (PPE). The prolonged use of facial masks may result in several skin problems, mostly irritant contact dermatitis (ICD), but also flare‐ups of pre‐existing dermatoses (eg, rosacea), contact urticaria, allergic contact dermatitis (ACD), and impetigo. ,

In the index case prolonged use of ear‐looped mask‐induced Köebner phenomenon in the supraauricular area and adjoining scalp. Interestingly the phenomenon induced the lesions over the left ear, probably due to the common practice that the loop is hooked on the right ear first and then to the left ear. The left ear loop is put not fitting to the postauricular groove perfectly and in the process of talking, etc, with the mask on, puts pressure and the incidental injury more on the left side. The Köebner phenomenon in psoriasis is a common response to skin trauma/injury, may be mild or severe.

It has been shown that the disruption of a functional and structural permeability barrier is critical for the appearance of psoriasis as Köebner reaction. Accordingly, the importance of the rupturing of the epidermis in initiating the Köebner response has been well documented. Along with it, an important role of secondary dermal reactions in the development of psoriatic lesions at the site of injury has also been defined.

The studies show that wearing face masks is linked to development of itch, and scratching can lead to incorrect use of face masks, resulting in reduced protection.

Persons with preexisting dermatoses including psoriasis, who are prone to develop Köebner phenomenon, should be advised not to use ear‐looped face masks during this pandemic.

They should be encouraged to use masks without ear‐loop or with gaiters of good length which can be tied to scalp bypassing the ear. Another idea to reduce this problem is to tie the mask loop on occipital area with a plastic band. Face mask with ties or face mask with bands is advocated in such patients.