Wolf's Isotopic Response: Report of a Case and Review of Literature

Arriving at SKINTED (Surgery of the Knee, Injury to the Infrapatellar Branch of the Saphenous Nerve, Traumatic Eczematous Dermatitis): A Case Report

Surgery of the knee, injury to the infrapatellar branch of the saphenous nerve, traumatic eczematous dermatitis (SKINTED) is a postsurgical localized dermatitis specifically linked to total knee arthroplasty (TKA). It is due to autonomic denervation following surgically inflicted nerve injury. It develops several months to years following a surgical trauma. It is being referred to by various names in the literature. Locoregional immune dysfunction due to lymphatic injury after surgery is the currently accepted theory. It must be distinguished from atopic dermatitis, allergic contact dermatitis/sensitization induced by topical medications or implanted metal hypersensitivity dermatitis, and post-traumatic eczema/dermatitis. We present a case of an elderly female patient in her 50s with dry eczematous lesions over the lateral aspect of the surgical incision over both knees developed three months following bilateral total knee replacement (TKR) done in view of osteoarthritis. The patient responded well to topical corticosteroid and emollient treatment. We have also reviewed the literature to provide an overview of potential concepts of etiopathogenesis described in the literature and to clear up any ambiguity surrounding various labels given to this entity.

Keloids After Herpes Zoster: Report of Wolf's Isotopic Phenomenon and Literature Review

Wolf's isotopic response (WIR) refers to the appearance of a new skin disorder at the exact site of an unrelated skin disorder that had previously been cured. The most common primary skin disease in which WIR occurs is herpes zoster. Despite numerous theories being put forward to explain this occurrence, including viral, vascular, immunological, and neurological hypotheses, the pathogenesis of WIR after herpes zoster remains unclear. We report the case of a 76-year-old patient who presented with keloids at the site of the original herpes zoster. Based on this observation and a review of the literature, The clinical characteristics and possible theoretical reasons for keloids after herpes zoster will be discussed.

A Case of Isotopic Response Presented with Eosinophilic Pustular Folliculitis

This is a 58-year-old woman who has had itching on her right back for 10 days; a month ago she developed blisters on her right back with no apparent cause and pain, and was diagnosed with "herpes zoster". Erythema and blisters with itching reappeared 10 days ago on the right side of the back, where the original blisters had subsided. The histopathological manifestations of the lesions were: mild hyperkeratosis of the epidermis, pustules within the stratum corneum, irregular proliferation of the spinous layer, spongiosis, local destruction of the basal layer, infiltration of eosinophils, neutrophils, histiocytes and scattered plasma cells in the dermis and subcutis. According to the medical history, clinical manifestations and histopathology of the lesions, the diagnosis was Wolf's isotopic response after herpes zoster.

Wolf's isotopic response: A case of dermatomal granuloma annulare after COVID-19 vaccination

The SARS-CoV-2 pandemic was announced in March 2020, with the first vaccines becoming available later that year. Although generally well tolerated, there have been reports of skin reactions occurring after receiving COVID-19 vaccines, with a rare occurrence of granuloma annulare. Granuloma annulare can occur secondarily to herpes zoster infection in a phenomenon known as Wolf's isotopic response (WIR). WIR has been described to often occur after herpes zoster virus infection, at the location of the healed shingles rash, termed 'post-herpetic isotopic response' (PHIR). We present the first reported case of PHIR with granuloma annulare after the Moderna COVID-19 vaccination series. This reported reaction should not limit receipt of the COVID-19 vaccine, but awareness of this association can minimise additional work-up and treatment.

Wolf's Isotopic Response of Eosinophilic Dermatitis After Herpes Zoster Infection: Case Reports and Literature Review

Wolf’s post-zoster isotopic response refers to the occurrence of an unrelated new skin disorder at the same site of a healed skin lesion. Mechanism of this dermatological phenomena after herpes zoster infection remains unclear. In this study, we present three rare cases of eosinophilic dermatitis following herpes zoster infection. Erythematous infiltrative plaques or scattered red papules were found in all patients after remission of a previous herpetic infection. Skin biopsy revealed dermal perivascular eosinophilic infiltration, which was histologically confirmed as eosinophilic dermatitis. Based on the clinical timeline and histopathological characteristics, we supposed that the secondary lesion to be an isotopic response of Wolf. Skin lesion in one of the current patients overlapped with her tattoo, suggesting that tattoos might also predispose patients to post-zoster isotopic events. Topical corticosteroid was applied and all patients achieved remission. We also summarize the epidemiological, clinical and histopathological characteristics of the post-zoster eosinophilic dermatitis based on review of previous literature focusing on Wolf’s isotopic response and secondary inflammatory dermatological disorders.

Isotopic response of labetalol-associated lichen planus pemphigoides on an old radiation site: A case report

Over the years, the occurrences of different types of skin disorders arising from radiation sites have been observed and studied. Examples include autoimmune blistering diseases such as pemphigus, pemphigoid, and interface or inflammatory reaction patterns such as lichen planus, lupus erythematosus, and Stevens-Johnson syndrome. The phenomenon whereby a new skin disorder arises from a previously healed or irradiated site is called an isotopic response, described as a type of Koebner phenomenon. Ionizing radiation itself can profoundly affect the skin. Both early and late changes can present, which typify the progression of changes following irradiation of the skin. Herein, we report a rare case of labetalol-associated lichen planus pemphigoides that occurred at the site treated with radiation for a soft tissue malignancy after 19 years as a result of an isotopic response. The rash was well-controlled after therapy and kept a 4-year remission. The same skin reaction recurred after the reintroduction of labetalol 4 years later.

A New Skin Manifestation at the Site of a Previously Healed Dermatosis: A Case of Wolf's Isotopic Response

Wolf's isotopic response (WIR) is an uncommon phenomenon that refers to the occurrence of a new skin condition at the location of a previously healed dermatosis. We describe an unusual manifestation of bacterial furunculosis which arose as an isotopic response following a herpes zoster episode. The initial skin disease in most cases is herpes zoster and the isotopic response is a granulomatous reaction.  A 65-year-old female with a history of chronic lymphocytic leukemia (CLL) and currently on chemotherapy regimen presented with a pustular skin rash on the posterior scalp extending to the posterior right neck and shoulder. Prior to this presentation, the patient was treated for three weeks with valacyclovir for herpes zoster infection which improved her skin condition. During the current hospitalization, the patient's wound cultures from the pustule revealed the growth of methicillin-resistant Staphylococcus aureus (MRSA). Although the patient was on immunosuppressive therapy, her white blood cell (WBC) count increased to 9.9 x 10³/μL. After receiving vancomycin and valacyclovir, her cutaneous condition eventually improved. She was transitioned to oral clindamycin and discharged to a rehabilitation facility. This case describes an immunocompromised patient who was treated for herpes zoster, improved after treatment, and then developed MRSA furunculosis at the same site. It is of significance to report such manifestations, especially in immunocompromised patients, as it could be underdiagnosed. It is also important to inquire about the patients' herpes-related medical history because herpes is the most common initial dermatosis reported in the literature. In such cases of suspected WIR, it is vital to obtain a biopsy before starting treatment with antiviral medication to rule out the possibility of malignancy.

Extensive Verrucae over Healed Pemphigus Vulgaris Lesions in an Immunocompetent Female: A Rare Presentation of Wolf's Isotopic Response

Wolf's isotopic response refers to the occurrence of a skin disorder at the site of another unrelated and already healed skin disease. The cases described so far in the literature include herpes (simplex or zoster) as the primary disease in most cases and a myriad of skin diseases as the secondary disease. Here, we report a case where extensive verrucae developed over the sites of healed lesions of pemphigus vulgaris, in an immunocompetent female. Pemphigus vulgaris being the primary disease and absence of verrucae over normal skin makes this case, a rare presentation.

Becker's Nevus with Recurrent Eczema Limited to the Nevus Lesion

Several dermatoses have been reported in association with Becker's nevus. Eczematous dermatitis associated with Becker's nevus is extremely rare, described in only two previous case reports. We report a case of 21-year-old male with recurrent eczema lesions which were always localized within the underlying Becker's nevus lesion. This case may be explained as a Wolf's isotopic response-like phenomenon.

Categorization of and comments on isomorphic and isotopic skin reactions

Locus minoris resistentiae (lmr) can be defined as a site of the body that offers lesser resistance than the rest of the body to the onset of disease. The well-known Köbner phenomenon is itself a clear example of lmr in dermatology. The new term locus maioris resistentiae (LMR), a site of the body that offers greater resistance than the rest of the body to the onset of disease, defines the opposite condition. Renbök phenomenon (reverse Köbner's isomorphic response) typically represents an example of LMR.

Wolf's Isotopic Response: Varicella Within a Prior Immunization Reaction Site

Wolf's isotopic response describes the occurrence of a dermatologic condition at the site of a prior healed unrelated condition. Our report details a case of varicella occurring as a secondary condition at the site of a prior immunization reaction; herpesvirus infection has not been reported as a secondary condition in cases of Wolf's isotopic response before. Current hypotheses favor the involvement of neurohormonal modulation of local immunity in response to various forms of injury as a model for explaining these phenomena.