Response to 'A skin reaction with rust-like discolouration to mRNA COVID-19 vaccine'.

Editor

We have read with the utmost interest the content of the recent letter by Pasternack et al., which deals with a rare skin reaction following the mRNA COVID‐19 vaccine. Our report and the additional three cases discussed in the aforesaid letter suggests that this complication may be more common than appreciated or reported. In fact, a 30‐year‐old man with no significant past medical history was admitted to the hospital with multiple yellow‐orange discolouration of the right hand. The patient reported the onset of lesions one day after the first dose of the SARS‐COVID‐19 vaccine ‘pfizer’. In fact, a physical examination (Fig. 1) revealed multiple non‐infiltrated yellow‐orange macular patches symmetrically distributed on the metacarpophalangeal and the proximal interphalangeal joints of the right hand. However, there were no areas of ulceration, discharge or infection. Then, the remaining physical examination was normal. Moreover, a laboratory examination for the presence of hepatic enzymes, thyroid hormone, creatinine, urea and vitamin A levels showed no abnormality and all lesions subsided in 48 h with no recurrence.

Figure 1

Yellow‐orange macules symmetrically distributed on the joints of the right hand.

Cutaneous reactions have been reported after messenger RNA (mRNA)‐based COVID‐19 vaccines but are not well characterized, however, delayed large local reactions were the most common. ,

Comparatively, our young patient, who had no medical history of allergy, had not experienced another adverse event. In fact, these skin reactions would suggest a hemosiderin pigmentation but resolves too rapidly to be explained as such. Therefore, another mechanism was proposed, which is local capillary leakage due to the vaccination and some type of immunologic reactions located in the dermis/epidermis junction. However, despite the benign character and the harmless evolution of this side effect of the vaccines, its understanding is important to avoid unnecessary investigations and reassure the patient.

Conflict of interest

All authors declare that there is no conflict of interest.

Funding sources

We received no funding to support for this work.