Two cases of reactive perforating collagenosis arising at the site of healed herpes zoster

Herpes zoster granulomatous dermatitis: histopathologic findings in a case series

Several types of cutaneous reactions have been reported to arise at the site of herpes zoster (HZ) infection weeks to years after the acute disease. Among these, granulomatous reactions are the most frequently reported. In this study, we describe the spectrum of histopathologic findings of HZ granulomatous reactions observed in 26 patients with cutaneous lesions confined to the area of previous HZ eruption and compare them with biopsy specimens taken from 25 patients with acute HZ. All patients with persistent reactions from whom history was available presented within 12 weeks of the onset of the acute eruption. The most frequent findings were interstitial granulomatous dermatitis with lymphocytes, histiocytes and multinucleated giant cells displaying elastophagocytosis and a perineural, perivascular and perieccrine mononuclear inflammatory infiltrate rich in lymphocytes and plasma cells. Less common features included intra-arrector and peri-arrector pili granulomas, follicular dilatation and hyperkeratosis, and vasculitis. Specimens from patients with acute HZ were found to have small numbers of perineural plasma cells and most had subtle granulomatous inflammation, in patterns similar to the group with late granulomatous reactions. Our findings suggest that granulomatous reactions to varicella zoster virus represent a persistent evolving inflammatory reaction after acute infection.

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.

[Acquired reactive perforating collagenosis following herpes zoster as isotopic response?]

Reactive perforating collagenosis is a disease whose pathogenesis is still not fully understood. Histological findings are degenerated collagen bundles which are arranged in vertical direction penetrating the epidermis into a dome-shaped crater. Usually diabetes mellitus and renal failure can be found among patients with reactive perforating collagenosis. To date, there have been five cases described where the eruption of reactive perforating collagenosis followed herpes zoster infection. This could be a form of Wolf's isotopic response, a term that is used for dermatoses which arise after the healing of a preexisting dermatosis. We report the sixth case of a herpes zoster-associated reactive perforating collagenosis and discuss the current literature.

Acquired reactive perforating collagenosis: current status

Acquired reactive perforating collagenosis is a unique perforating dermatosis, characterized clinically by umbilicated hyperkeratotic papules or nodules and histologically by a focal hyperkeratosis in direct contact with transepidermal perforating dermal collagen. Several inflammatory or malignant systemic diseases may coexist with acquired reactive perforating collagenosis. The possible biochemical or immunological mechanisms of the systemic diseases, potentially responsible for the development and appearance of acquired reactive perforating collagenosis, are still under investigation. Several topical treatments, ultraviolet B phototherapy and allopurinol p.o. administration may be effective.

Acquired Perforating Dermatosis in a Patient with Poland Syndrome

Acquired perforating dermatosis (APD) is characterized by umbilicated 1- to 10-mm-measuring papulonodules with a central adherent oystershell-like keratotic plug, typically on the dorsa of the hands, forearms and over the knees. APD is associated with systemic diseases, especially diabetes mellitus and/or renal failure. Histologically the lesions show transepidermal elimination of altered dermal components into a cup-shaped epidermal depression. We present a 69-year-old man with coexisting APD and Poland syndrome (PS), an association not yet described. PS (OMIM 173800) is a rare congenital anomaly consisting of unilateral partial or total absence of the greater pectoralis muscle and ipsilateral symbrachydactyly. Most cases of PS are sporadic as it was in our case. Our patient had, in addition, an untreated diabetic condition, hyperuricaemia, dilated cardiomyopathy and a very recent pulmonary embolism. He responded to therapy with allopurinol.

Reactive perforating collagenosis: a condition that may be underdiagnosed

Reactive perforating collagenosis is a perforating disorder developing in adults, usually in association with diabetes mellitus or renal failure. We present three cases diagnosed at the Royal Prince Alfred Hospital in a 5 month period. All three patients had long-standing diabetes mellitus, hypertension, hypercholesterolaemia and ischaemic heart disease. Each patient presented with generalized pruritus and a papular eruption across the trunk and limbs. More than one biopsy or multiple levels were needed before the diagnostic histological features were seen. The first patient responded to 0.5% phenol with 10% glycerine in sorbolene cream. The second patient did not respond to topical betamethasone diproprionate 0.5 mg/g cream and antihistamines (hydroxyzine 25 mg nocte) and required narrow-band ultraviolet (UV) B. The third patient, having failed to respond to topical betamethasone diproprionate 0.5 mg/g cream and wet dressings, antihistamines (hydroxyzine 25 mg tds and doxepin 50 mg nocte) and UVB required acitretin 25 mg orally per day. Because reactive perforating collagenosis responds to treatment, we believe this condition should be considered in patients with diabetes mellitus or renal failure presenting with pruritus and that biopsy of intact lesions may need multiple levels to help establish the diagnosis.