Atypical presentations of bullous pemphigoid: Clinical and immunopathological aspects

Nonbullous pemphigoid: A systematic review

BACKGROUND

Bullous pemphigoid is an autoimmune disease that typically presents with tense bullae and severe pruritus. However, bullae can be lacking, a subtype termed nonbullous pemphigoid.

OBJECTIVE

To summarize the reported characteristics of nonbullous pemphigoid.

METHODS

The EMBASE and MEDLINE databases were searched using "nonbullous pemphigoid" and various synonyms. Case reports and series describing nonbullous pemphigoid were included.

RESULTS

The search identified 133 articles. After selection, 39 articles were included, presenting 132 cases. Erythematous, urticarial plaques (52.3%) and papules/nodules (20.5%) were the most reported clinical features. The mean age at presentation was 74.9 years. Histopathology was commonly nonspecific. Linear depositions of IgG and/or C3 along the basement membrane zone were found by direct immunofluorescence microscopy in 93.2%. Indirect immunofluorescence on salt-split skin was positive in 90.2%. The mean diagnostic delay was 22.6 months. A minority of patients (9.8%) developed bullae during the reported follow-up.

LIMITATIONS

Results are mainly based on case reports and small case series.

CONCLUSION

Nonbullous pemphigoid is an underdiagnosed variant of pemphigoid that most often does not evolve to bullous lesions and mimics other pruritic skin diseases. Greater awareness among physicians is needed to avoid delay in diagnosis.

Cutaneous Eruptions in Patients Receiving Immune Checkpoint Blockade: Clinicopathologic Analysis of the Nonlichenoid Histologic Pattern

Cutaneous eruptions are among the most common immune-related adverse events (irAEs) associated with anti-programmed cell death protein 1/programmed cell death ligand 1 therapy, and are often clinically and histologically characterized as lichenoid. Nonlichenoid patterns may also occur and are likely to be encountered by surgical pathologists, given the increasing clinical use of these agents. The purpose of this study is to describe the histopathologic features of nonlichenoid cutaneous irAEs from patients receiving anti-programmed cell death protein 1/programmed cell death ligand 1 therapies for a variety of underlying advanced malignancies. Sixteen patients with 17 biopsied eruptions were included from 2 academic institutions with extensive experience administering and monitoring responses to immune checkpoint blockade as well as treating the potential side effects. Eruptions occurred a median of 10 days (range, 1 d to 11.4 mo) after treatment initiation. Nearly half of specimens demonstrated either a psoriasiform/spongiotic or an urticarial-type reaction pattern on histologic review. Patterns consistent with Grover disease, bullous pemphigoid, and granulomatous dermatitis were also observed. Nearly two-thirds of patients required systemic corticosteroids for treatment of the cutaneous irAE, and 19% of patients discontinued immunotherapy due to their skin eruptions. 75% of patients showed an objective antitumor response. The diverse array of nonlichenoid cutaneous irAE presented here should reflect and inform the scope of histologic patterns encountered by the practicing surgical pathologist. Such eruptions are seen in patients with a variety of underlying tumor types, many of whom ultimately demonstrate a favorable response to immune checkpoint blockade.

High-Frequency Color Doppler Sonography of Bullous Pemphigoid: Correlation With Histologic Findings

Bullous pemphigoid is the most frequent autoimmune-mediated blistering skin disease, belonging to the group of subepidermal bullae. We performed high-frequency color Doppler sonography in 3 cases of bullous pemphigoid, in bullous and adjacent non-bullous skin, which showed homogeneous sonographic findings. Subepidermal cystic structures with dermal hypoechogenicity were observed in bullous skin. In nonbullous skin, the dermis showed hypoechogenicity compared to normal skin. Color Doppler signals were increased in both areas. These findings correlate histologically with subepidermal bullae and dermal inflammatory infiltrates.

Two cases of annular erythema without bullous lesions by autoimmune blistering diseases

Although annular erythema is usually observed as one of the cutaneous manifestations of Sjögren's syndrome or subacute cutaneous lupus erythematosus, autoimmune blistering diseases also present with annular erythema. However, bullous lesions are not always found, and there is a rare type without bullous lesions. We present two cases of autoimmune blistering diseases showing annular erythema without bullous lesions. It is important to perform direct or indirect immunofluorescence examination when we encounter multiple annular erythema.

Oral mucosal manifestations of autoimmune skin diseases

A group of autoimmune diseases is characterised by autoantibodies against epithelial adhesion structures and/or tissue-tropic lymphocytes driving inflammatory processes resulting in specific pathology at the mucosal surfaces and the skin. The most frequent site of mucosal involvement in autoimmune diseases is the oral cavity. Broadly, these diseases include conditions affecting the cell-cell adhesion causing intra-epithelial blistering and those where autoantibodies or infiltration lymphocytes cause a loss of cell-matrix adhesion or interface inflammation. Clinically, patients present with blistering, erosions and ulcers that may affect the skin as well as further mucosal surfaces of the eyes, nose and genitalia. While the autoimmune disease may be suspected based on clinical manifestations, demonstration of tissue-bound and circulating autoantibodies, or lymphocytic infiltrates, by various methods including histological examination, direct and indirect immunofluorescence microscopy, immunoblotting and quantitative immunoassay is a prerequisite for definitive diagnosis. Given the frequency of oral involvement and the fact that oral mucosa is the initially affected site in many cases, the informed practitioner should be well acquainted with diagnostic and therapeutic aspects of autoimmune dermatosis with oral involvement. This paper reviews the pathogenesis and clinical presentation of these conditions in the oral cavity with a specific emphasis on their differential diagnosis and current management approaches.