Sera from patients with toxic epidermal necrolysis contain autoantibodies to periplakin

Mucosal Fixed Drug Eruption with Oral, Conjunctival, Nasal, and Anal Lesions: A Case Report

is missing (Short communication).

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.

Laboratory diagnosis of paraneoplastic pemphigus

BACKGROUND

Paraneoplastic pemphigus (PNP) is a multiorgan disease characterized by antibodies against plakins, desmogleins and the α2-macroglobulin-like-1 (A2ML1) protein, in association with an underlying neoplasm. Accurate diagnosis relies on the demonstration of these autoantibodies in serum.

OBJECTIVES

To evaluate the value of different laboratory techniques in the serological diagnosis of PNP.

METHODS

We performed immunoblotting, envoplakin (EP) enzyme-linked immunosorbent assay (ELISA), indirect immunofluorescence (IIF) on rat bladder, radioactive immunoprecipitation and a nonradioactive combined immunoprecipitation-immunoblot assay. Additional assays included BP180 ELISA and BP230 ELISA. We included the sera of 19 patients with PNP and 40 control subjects.

RESULTS

The sensitivities were 63% for anti-EP ELISA, 74% for rat bladder IIF, 89% for immunoblotting, 95% for radioactive immunoprecipitation and 100% for nonradioactive immunoprecipitation. Specificities ranged from 86% to 100%. The BP180 and BP230 ELISAs had low sensitivity and specificity for PNP. The combination of rat bladder IIF and immunoblot showed 100% sensitivity and specificity. The analysis of sequential PNP sera showed that antibody titres may decrease over time, possibly resulting in negative outcomes for EP ELISA and rat bladder IIF studies.

CONCLUSIONS

The detection of autoantibodies against EP and periplakin, or A2ML1 by immunoprecipitation is most sensitive for PNP. The combination of rat bladder IIF and immunoblotting is equally sensitive and highly specific, and represents an alternative valuable and relatively easy approach for the serological diagnosis of PNP.

Clinical and immunopathological spectrum of paraneoplastic pemphigus

BACKGROUND

Paraneoplastic pemphigus (PNP) is a rare life-threatening autoimmune bullous disorder. The clinical picture is often polymorphous and blisters may be absent. Autoantibodies are directed against several target antigens, including plakins and desmogleins. PNP has a high mortality rate that does not directly depend on the malignancy of the neoplasm. No generally accepted diagnostic criteria for PNP have been defined.

PATIENTS AND METHODS

On the basis of four selected PNP patients and the relevant literature, the spectrum of clinical and immunopathological findings as well as pathogenesis and treatment options of PNP are presented.

RESULTS

In addition to a neoplasm, severe stomatitis and the presence of autoantibodies against periplakin and envoplakin are characteristic for PNP. Based on the presented data, diagnostic criteria are proposed.

CONCLUSIONS

Knowledge of the polymorphous clinical picture and the complex autoantibody response is essential for an early diagnosis of PNP which has implications for both prognosis and rapid initiation of treatment.