Paraneoplastic pemphigus mimicking toxic epidermal necrolysis: An underdiagnosed entity?

Absence of Epidermal Antibodies in Stevens-Johnson Syndrome/Toxic Epidermal Necrolysis Patients but Beware of Single Positive Results

Background

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are rare and potentially life-threatening mucocutaneous blistering diseases that clinically can resemble autoimmune bullous diseases. Moreover, it has been shown that autoantibodies against epidermal proteins are present in SJS/TEN.

Objectives

To establish the presence of antibodies against desmosomal and hemidesmosomal proteins in confirmed SJS/TEN patients.

Methods

Serum of SJS/TEN patients diagnosed based on clinical criteria, e.g., epidermal detachment with erosions and severe mucosal lesions, (suspicion of) a culprit drug, and matching histologic results was evaluated by various techniques, e.g., indirect immunofluorescence on monkey esophagus, salt split skin and rat bladder, immunoblotting (IB) and immunoprecipitation (IP), ELISAs against desmogleins and BP180, keratinocyte footprint assay, and keratinocyte binding assay.

Results

A total of 28 patients were included in this study, 15 men and 13 women with a mean age of 56 years. In most patients, none of the serological tests were positive. In two patients, an elevated DSG3 titer was found suspicious for pemphigus vulgaris. Three patients had elevated NC16a titers, suggesting bullous pemphigoid. However, in all these patients, no other tests were positive and in these patients, the biopsy for direct immunofluorescence showed no evidence for an autoimmune bullous disease. Three patients showed reactivity against rat bladder rat bladder; these were, however, completely negative for A2ML1, envoplakin, and periplakin in the IB as well as the IP.

Conclusions

Serological analysis for desmosomal and hemidesmosomal antibodies is reliable to rule an autoimmune bullous disease in patients with suspected SJS/TEN. However, one should not rely on one single test method since false positive results can occur. Moreover, this study also makes it less plausible that antibodies against desmosomal and/or hemidesmosomal components are involved in the pathogenesis of SJS/TEN.

Toxic Skin Reactions Should Be Differentiated from Allergic Reactions to Chemotherapeutic Drugs in Children: A Case Series and Review of the Literature

Background: Chemotherapeutic drugs can lead to a wide spectrum of cutaneous findings, ranging from nonimmune toxic reactions to severe immune-mediated hypersensitivity reactions. The aim of this study was to evaluate the clinical, histopathological features, and prognosis of toxic skin reactions to chemotherapeutic drugs and to compare them with characteristics of immune-mediated reactions in children with malignancies. Methods: The medical records of all children with cancer who experienced skin reactions after chemotherapy administration and diagnosed as a toxic skin reaction between 2010 and 2022 were retrospectively analyzed. The diagnosis was re-evaluated and differentiated from other similar disorders by using clinical manifestations, photodocumentation, and histopathological findings. Results: A total of 17 children aged 2-17 years were involved: toxic erythema of chemotherapy (TEC) in 14 children, methotrexate-induced epidermal necrosis in 2 children, and toxic epidermal necrolysis (TEN)-like TEC in 1 child. The most commonly implicated drug was methotrexate. Most patients recovered rapidly after drug cessation and supportive measures. In 10 of the 17 patients, reintroduction of the culprit chemotherapeutic drug at reduced doses or increased dosage intervals was possible without any recurrence. Six patients could not receive further doses since they deceased due to sepsis and other complications. Conclusions: Cutaneous toxic eruptions to chemotherapeutic drugs may present with a severe phenotype resembling Stevens-Johnson syndrome/TEN. An accurate diagnosis prevents potentially harmful therapeutic interventions, withholding of chemotherapy, and erroneous assignment of drug allergies.

Pemphigus vulgaris mimicking Steven-Johnson syndrome/toxic epidermal necrolysis: report of an unusual case

Pemphigus vulgaris (PV) is an autoimmune blistering disease affecting the skin and mucosa. It clinically presents as painful erosions, mainly in the oral cavity, and flaccid blisters and erosions on the skin. Steven-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN) is a severe mucocutaneous drug hypersensitivity reaction characterized by painful, dusky, erythematous eruptions that often progress to blisters, erosions, and extensive epidermal detachment accompanied by systemic symptoms. Herein, we report the case of a 48-year-old man who presented with extensive skin and mucosal lesions following the ingestion of an unknown medication. The patient's symptoms clinically mimicked SJS, and accordingly, a preliminary diagnosis of SJS/TEN was made. However, clinical investigation of skin biopsy and direct immunofluorescence assay results indicated PV, and a final diagnosis of PV was established.

Paraneoplastic Pemphigus Mimicking Pemphigus Vulgaris Associated With Castleman Disease

Paraneoplastic pemphigus (PNP) is a rare bullous disease with a polymorphic presentation. Diagnosis can be difficult because it can mimic other bullous diseases, while the underlying neoplasm may be completely asymptomatic. We present the case of a 19-year-old female with a four-year history of exclusively oral bullous lesions, mimicking pemphigus vulgaris, before the diagnosis of a retroperitoneal Castleman disease. While PNP is a severe and sometimes deadly condition, our patient had a mild and long evolution on minimal treatment, with complete resolution after tumor excision. Practitioners should be aware of PNP in young patients presenting with bullous disease and should conduct prompt systemic investigations in refractory or long-evolving cases, even when PNP diagnostic criteria are not fully met.

TEN mimics: Classification and practical approach to toxic epidermal necrolysis-like dermatoses

Toxic epidermal necrolysis (TEN) is an acute life-threatening dermatologic emergency. However, many dermatoses can present with a TEN-like eruption. Those "TEN-mimics" are a true diagnostic challenge and an alarming differential diagnosis to such a serious condition. Herein, we will expose and classify the landscape of TEN-mimics. Also, the key differentiating clinical and/or laboratory points will be highlighted to help an accurate diagnosis of either a TEN or a TEN-like presentation.

Rare Case of Paraneoplastic Pemphigus Associated With Prostatic Cancer

ABSTRACT

The combination of paraneoplastic pemphigus and prostate cancer is extremely unusual and has not been reported yet. Paraneoplastic pemphigus is caused by tumor-induced autoantibodies, which cause damage to the skin and mucosa. The essential treatment is active tumor control. Our patient received a robot-assisted radical prostatectomy and glucocorticoid therapy to improve his condition and relieve his skin lesions.

A Case of Paraneoplastic Pemphigus as a Preceding Manifestation of Underlying Follicular Lymphoma Treated with R-CHOP

Paraneoplastic pemphigus is a rare, life-threatening disorder associated with an underlying neoplasm, which presents with painful stomatitis and polymorphous skin lesions. Successful diagnosis of paraneoplastic pemphigus can lead to the diagnosis and treatment of the underlying malignancy. However, involvement of the respiratory system is typically unresponsive to treatment. Herein, we report the case of a 44-year-old female diagnosed with paraneoplastic pemphigus with underlying follicular lymphoma treated with a chemotherapy regimen including rituximab. Her skin lesions and underlying lymphoma responded to treatment, but bronchiolitis obliterans continued to progress and resulted in fatal respiratory failure.

Paraneoplastic Pemphigus: An Indication for Treatment in Chronic Lymphocytic Leukemia

Paraneoplastic disorders are rare multiorgan diseases associated with hematological malignancies such as chronic lymphocytic leukemia (CLL). Some of these paraneoplasms manifest as cutaneous lesions, appearing as a simple rash, ulcers or skin thickening. The pathogenesis for this process has been described as development of certain autoimmune reactions against cell wall antigens and proteins. An example is paraneoplastic pemphigus (PNP) which manifests as cutaneous bullae. Bullae may occur anytime during the course of the malignancy i.e. acute phase or remission. Diagnosis involves evaluation of clinical findings, serology and presence of characteristic histological findings. Its pathogenesis is described as development of auto-antibodies against cell junctional and basement membrane proteins. Presence of paraneoplasms has been associated with poorer prognosis and increased mortality in hematological malignancies including CLL. Currently, there are established indications for the treatment of CLL; however, presence of paraneoplasms as an indication for treatment is unclear. Patients with paraneoplasms who underwent expeditious treatment have exhibited better clinical outcomes. Herein we describe a case of a CLL patient in remission presenting with PNP and its response to treatment.

Advances in the diagnosis of autoimmune bullous dermatoses

Autoimmune bullous dermatoses are defined by autoantibodies directed against adhesion proteins in the epidermis or basement membrane zone, resulting in blister formation on the skin and mucosa. Diagnosis depends on lesional biopsy for histopathology and perilesional biopsy for direct immunofluorescence. Additional diagnostic methods include indirect immunofluorescence, enzyme-linked immunosorbent assay, and immunoblot (Western blot), which may be selected in specific clinical scenarios due to improved sensitivity and/or specificity. This contribution reviews the available evidence supporting the use of each method to provide a practical reference for clinicians when diagnosing autoimmune bullous disorders. Techniques and cost are reviewed, and newer diagnostic techniques with potential for clinical application are.