Wolf's isotopic response: Trichophyton rubrum folliculitis appearing on a herpes zoster scar

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.

Trichophyton rubrum Skin Folliculitis in Behçet's Disease

A 29-year-old patient with Behçet’s disease based on three major criteria (i.e., oral ulceration, genital ulceration, and eye lesion) presented with intractable pruritus associated with pinpoint red nodules involving the hair follicles of the back along with steroid-refractory local treatment. Simple light microscopic examination of a skin scraping revealed fungal contamination, and culture on Sabouraud’s medium confirmed Trichophyton rubrum as the agent of folliculitis. Behçet’s disease is characterized by recurrent attacks of acute inflammation. Although the diagnosis of sterile folliculitis-like disorder is currently retained among patients with Behçet’s disease, especially in the lower part of the body, it resembles dermatophytic folliculitis, which can be related to immunosuppressive therapy. Hence, patients with recalcitrant folliculitis predominating on the back who are receiving immunosuppressive treatment should be evaluated for fungal infection, as recognition of this disease may enable earlier diagnosis and treatment.

Wolf's post-herpetic isotopic response: Infections, tumors, and immune disorders arising on the site of healed herpetic infection

Herpes simplex viruses (HSV-1/HSV-2) and varicella-zoster virus (VZV) have several characteristics in common. Both are epidermoneurotropic, cause skin eruptions accompanied by sensory symptoms (itch, pain), damage peripheral sensory nerve fibers and cutaneous nerve endings, and interfere with neuromediator release, which can alter local mechanisms of immune control. For this reason, herpes-infected areas may become a preferential location for the subsequent onset of immunity-related skin disorders (infections, tumors, and dysimmune reactions), an event first reported by a neurologist and focused on by two brothers, a dermatologist and a pediatrician. The phenomenon therefore named Wolf's post-herpetic isotopic response (PHIR) refers to the occurrence of a new skin disorder at the site of a previous and already healed herpetic eruption (herpes zoster in most cases). Until now, we have been able to gather 189 well-documented cases of PHIR (all reported in the reference section), but our list is far from being complete. Some of the most emblematic cases are briefly described here. In some circumstances, the opposite of PHIR occurs, with diffuse skin disorders or eruptions that selectively spare herpes-infected areas (Wolf's post-herpetic isotopic nonresponse). Experimental investigations with patch testing have been performed in seven patients who were sensitized to nickel and had had herpes zoster in the past years. The tests were carried out bilaterally on the affected dermatomes and on the unaffected contralateral ones. The uneven immune responses we obtained have shown that the immune behavior of an herpes zoster-affected dermatome can be different from that of the corresponding contralateral dermatome, thus supporting the existence of immune dysregulation in herpes-infected areas.

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

“Wolf's isotopic response” refers to the occurrence of a new dermatosis at the site of previously healed dermatosis. A number of factors including viral, neural, vascular, and immunologic factors have been implicated in the causation of this peculiar response but none has been proven conclusively. Here, we report a case where lichen planus developed at the site of dermatofibrosarcoma protruberans that had been previously treated with surgery and radiotherapy. We also put forth a hypothesis on the genesis of isotopic response considering the above mentioned factors.

Volf’s isotopic response

The term of “isotopic response” was offered by R. Wolf and co-authors in 1995 and means the development of the new dermatosis at the place of already existing initial one, which has already regressed and is not directly referred to the first one. The article describes the essence of the phenomena and most important clinical cases. Such pathogenic mechanisms as viral, immunologic, vascular, neurogenic theory are being discussed, as well as the immunocompromised site concept. The commonality and the difference of the isotopic response and of the isomorphic Kobner’s phenomenon are being analyzed. Two clinical cases are provided.

Granuloma annulare on herpes zoster scars in a Hodgkin's disease patient following autologous peripheral stem cell transplantation

Various cutaneous lesions including granulomatous reactions may occur at sites of resolved herpes zoster infection. A 46-year-old man with Hodgkin's disease developed localized granuloma annulare lesions on herpes zoster scars 3 months after allogeneic peripheral stem cell transplantation. This is the first case of granuloma annulare localized on herpes zoster scars that developed following peripheral stem cell transplantation.

Isotopic response after herpesvirus infection: an update

The term postherpetic isotopic response describes the occurrence of a new, unrelated disease that appears at the same location as a previously healed herpetic infection. When dealing with the pathogenetic mechanism involved in the isotopic response, several possibilities should be considered: a viral origin, an immunologic origin, a vascular origin, and a neural origin. The aim of this article is to review and discuss the different pathogenetic mechanisms with particular attention to new information related to the possible neural origin of this abnormal response of the skin.

Wolf's isotopic response: a case of zosteriform lichen planus on the site of healed herpes zoster

Based on histological findings, the patient had lichen planus. The clinical picture suggests Wolf's isotopic response on the site of healed herpes zoster. These conditions taken into account lead to the diagnosis of zosteriform lichen planus. Lichenoid papules in a dermatomal arrangement are extremely rare. The clinical, dermoscopic and histological features of this case are described.