Hui-Te Hsu, Hsuan-An Su, Yu-Chia Chen
From the Department of Dermatology, Far Eastern Memorial Hospital, New Taipei City, Taiwan

Date of Web Publication31-Oct-2023

Correspondence Address:
Yu-Chia Chen
Department of Dermatology, Far Eastern Memorial Hospital, New Taipei City
Taiwan

Source of Support: None, Conflict of Interest: None

Check

DOI: 10.4103/ijd.ijd_414_23

How to cite this article:
Hsu HT, Su HA, Chen YC. Wolf's isotopic response following COVID-19 vaccination. Indian J Dermatol 2023;68:589

Sir,

“Wolf's isotopic response” is a distinct phenomenon describing the occurrence of a new skin disorder at the site of another unrelated and already healed skin lesion.[1] We present a case of papulovesicular eruption arising in scars two days after COVID-19 vaccination, which was reminiscent of “Wolf's isotopic response.”

A 49-year-old woman presented with painful and itchy skin lesions over healed scars 2 days after Medigen's vaccination (MVC-COV1901) against COVID-19. One month prior to the vaccination, she was involved in a motorcycle accident that left abrasion wounds on her right forearm and right shin. The wounds healed in 3 weeks with the daily application of silver sulfadiazine cream. However, an acute papulovesicular eruption occurred in both sites of the scars 2 days post-vaccination [Figure 1]. She denied having a personal or family history of atopy or an eczematous condition. A skin biopsy showed spongiotic dermatitis with some eosinophils in the upper dermis [Figure 1]. Oral prednisolone (30 mg per day), antihistamine, and topical clobetasol propionate (0.05%) ointment were prescribed. Within three weeks, the papulovesicular eruptions resolved.

Figure 1: Recently healed scar on right forearm before COVID-19 vaccination (a); papulovesicular eruption occurred in the scar 2 days after COVID-19 vaccination (b); spongiotic dermatitis as intercellular edema with subcorneal, intraepidermal, and subepidermal vesicles; papillary dermal edema; and the presence of eosinophils in the dermis (Hematoxylin-eosin stain, 100x) (c)

Click here to view

Cutaneous adverse reactions associated with COVID-19 vaccines include delayed local hypersensitivity reactions, urticaria, morbilliform, papulovesicular, and pityriasis rosea-like eruptions.[2] The most commonly biopsied histologic pattern was a spectrum of spongiotic dermatitis.[2] A pronounced spongiosis corresponded to a robust papulovesicular reaction clinically.[2] In the present case, the strong temporal association and clinicopathological correlation indicated a vaccine-related papulovesicular reaction.

Interestingly, the eruption that exclusively appeared within the scars was reminiscent of “Wolf's isotopic response,” which refers to the occurrence of a new skin disorder at the site of another unrelated and already healed skin lesion.[1] A similar finding was reported by Ferreli et al.,[3] who observed bullous and granulomatous formation in surgical scars following COVID-19 mRNA vaccination. Meanwhile, Esfandiari et al.[4] reported a case of dermatomal granuloma annulare after Moderna vaccination, which was considered to be Wolf's isotopic response. Together with our case, we suggest that COVID-19 vaccination can trigger various cutaneous adverse reactions manifesting as Wolf's isotopic response.

Post-traumatic eczema was a differential diagnosis but the abrasions had healed completely before the eruption. It could be an idiopathic or isomorphic reaction in patients with endogenous eczematous condition, especially those with atopic diathesis. However, our patient did not have atopic diathesis or pre-existing eczema.

The concept underlying Wolf's isotopic response is the “locus minoris resistentiae.” It denotes a vulnerable site that is privileged for the subsequent development of diseases.[5] Several hypotheses have been proposed to explain the phenomenon, including viral, neural, immunological, and vascular etiologies.[1] The local neural damage from viral or other causes may alter the neuromediator signaling, resulting in a dysregulated immune response.[1],[5] The local vasculature changed by the primary insult may upregulate adhesion molecules and recruit immune cells to the same site.[1] The immune dysregulation and memory serve as fertile soil for the occurrence of the second disease.

We called attention to the Wolf's isotopic response following the COVID-19 vaccination. The risk of inflammation or a new disorder in scars should be taken into consideration before vaccination, especially if there is a recently healed wound.

Declaration of patient consent

Informed consent for publication was obtained from the patient.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

 

   References 
1.Mahajan R, De D, Saikia UN. Wolf's isotopic response: Report of a case and review of literature. Indian J Dermatol 2014;59:275-82.  
[PUBMED]  [Full text]  2.McMahon DE, Kovarik CL, Damsky W, Rosenbach M, Lipoff JB, Tyagi A, et al. Clinical and pathologic correlation of cutaneous COVID-19 vaccine reactions including V-REPP: A registry-based study. J Am Acad Dermatol 2022;86:113-21.  
    3.Ferreli C, Anedda J, Atzori L. Transient inflammation in surgical scars following Covid-19 mRNA vaccination. J Eur Acad Dermatol Venereol 2022;36:e530-1.  
    4.Esfandiari N, Benson P, Morley K. Wolf's isotopic response: A case of dermatomal granuloma annulare after COVID-19 vaccination. JEADV Clin Pract 2023;2:156-8.  
    5.Piccolo V, Baroni A, Russo T, Schwartz RA. Ruocco's immunocompromised cutaneous district. Int J Dermatol 2016;55:135-41.  
    
  [Figure 1]