Acantholytic Acanthoma Research Articles

Claudin-4 Upregulation in Acantholytic and Autoimmune-Mediated Bullous Disorders.

Claudin-4 is a key component of tight junctions, which play an important role in the formation of the epidermal barrier by forming a circumferential network in the granular layer that serves as a gatekeeper of the paracellular pathway. The aim of this study is to illustrate claudin-4 immunohistochemical staining patterns of different blistering disorders. We collected 35 cases, including two Hailey-Hailey disease, one Darier disease, three Grover disease, one acantholytic acanthoma, two warty dyskeratoma, 11 pemphigus vulgaris (PV) including six mucosal PV, and two pemphigus foliaceus. For comparison, we included five cases of normal skin, five eczema, and three bullous pemphigoid cases. Claudin-4 demonstrated weak-to-moderate expression in keratinocytes located in the stratum granulosum, keratinocytes surrounding hair follicles, and adnexal glands. Further, claudin-4 exhibited moderate-to-strong membranous staining in disrupted keratinocytes surrounding and within the acantholytic and bullous areas in 16/22 of the acantholytic cases (not seen in the six cases of mucosal PV) and all three bullous pemphigoids. This finding suggests that claudin-4 is upregulated in these conditions, which may be a compensatory response to the disrupted barrier function. This finding could shed light on the molecular mechanisms underlying disrupted barrier function in blistering disorders, independent of the specific underlying disease mechanism.

Acantholysis caused repeated hemorrhagic bullae in a case of acantholytic acanthoma

Acantholysis caused repeated hemorrhagic bullae in a case of acantholytic acanthoma

Acantholysis made repeated hemorrhagic bulla in a case of acantholytic acanthoma

Acantholysis made repeated hemorrhagic bulla in a case of acantholytic acanthoma

Acantholytic dyskeratotic acanthoma: a variant of a benign keratosis

Acantholytic acanthoma was originally described as a solitary lesion displaying histologic features of acantholysis without dyskeratosis. Solitary, non-genital lesions displaying confluent acantholysis and dyskeratosis have not been well described in the literature, clinically or histologically. We screened cases at our institution over a 6-month period and found 28 such lesions. Lesions were most often found on the trunk as a solitary papule, for which the clinical diagnosis was often basal cell carcinoma. There was a slight female predominance. Confluent acantholysis and dyskeratosis is a histologic pattern that may present as a solitary keratosis.

Changes of epidermodysplasia verruciformis in benign skin lesions: the EV acanthoma

Foci of histological changes of epidermodysplasia verruciformis (EV) were noted in five benign skin lesions. These skin lesions included an intradermal nevus, a pigmented seborrheic keratosis, an isolated papule on the forearm, a perianal lesion, and an acantholytic acanthoma. Because the changes resembled true EV so strongly despite the absence of clinical EV in these patients, we searched for EV-human papilloma virus (HPV) types in these skin lesions. Polymerase chain reaction (PCR) analysis on the formalin-fixed, paraffin-embedded blocks was performed. As a positive control, we included tissue from two HIV-positive patients with clinical EV proven by biopsy. Studies were also performed on five other archived biopsies that did not show changes of EV on multiple tissue sections. A nested PCR method detected EV-HPV types in three of the five benign skin lesions showing EV changes as well as in the positive controls. EV changes and EV-HPV can be found incidentally on biopsy in the absence of clinical EV; when such changes are the major histopathological finding in an isolated skin lesion, the lesion should be termed an EV acanthoma.

Acantholytic acanthoma

This article describes 31 examples of acantholytic acanthoma, a newly recognized, solitary, benign cutaneous tumor. Acantholytic acanthoma was typically an asymptomatic, keratotic papule or nodule. Patients ranged in age from 32 to 87 years (median 60 years); the ratio of men to women was 2:1; the most frequent clinical diagnosis was keratosis; and half of the growths were on the trunk of the body. Histologically, the lesions showed hyperkeratosis, papillomatosis, and acanthosis. Acantholysis was an outstanding finding in all cases; the patterns resembled pemphigus vulgaris, pemphigus vegetans, superficial pemphigus, or Hailey-Hailey disease, but no patient had evidence of any of these disorders. The term acantholytic is used because acantholysis is the outstanding histologic feature in these neoplasms; acanthoma was chosen because the growths are benign tumors of epidermal keratinocytes. The relationship of acantholytic acanthoma to acantholytic blistering disease is similar to that of solitary lichen planus-like keratosis to lichen planus and epidermolytic acanthoma to bullous congenital ichthyosiform erythroderma.

The benign acanthomas.

An important, yet neglected, problem in dermatopathology, is the evaluation of the benign acanthomas, the benign tumors of epidermal keratinocytes. The benign acanthomas may be simulated by lesions which are not benign (e.g. actinic keratosis), not tumors (e.g. normal plantar skin), or are not epidermal (e.g. dermatofibroma). In addition to normal (epidermoid) keratinization (e.g., seborrheic keratosis and related conditions), the variants of the benign acanthomas show a wide range of aberrant keratinization, including epidermolytic hyperkeratosis (epidermolytic acanthoma), dyskeratosis (warty dyskeratoma), acantholysis (acantholytic acanthoma), cornoid lamellation (porokeratosis), lichenoid hyperplasia (lichen planus-like keratosis), and absence of keratinization (clear cell acanthoma).