Oxidative stress in patients with endemic pemphigus foliaceus and healthy subjects with anti-desmoglein 1 antibodies

Abstract: Background: Previous studies have shown oxidative stress in pemphigus vulgaris and pemphigus foliaceus, nevertheless, it remains unknown whether a similar response is characteristic of endemic pemphigus foliaceus in Peru. Objectives: To determine the oxidative stress response in endemic pemphigus foliaceus patients and subjects with positive for anti-desmoglein1 antibodies (anti-dsg1) from endemic areas of Peru. Subjects and Methods: This is a cross-sectional study. The study population included 21 patients with Endemic Pemphigus foliaceus and 12 healthy subjects with anti-dsg1 antibodies from the Peruvian Amazon (Ucayali), as well as 30 healthy control subjects. Malondialdehyde, an indicator of lipid peroxidation by free radicals, was measured in serum. Results: We collected 21 cases of endemic pemphigus foliaceus, 15 of them with active chronic disease and 6 in clinical remission. Serum malondialdehyde values in patients with chronic active evolution and healthy subjects with anti-dsg1 antibodies were statistically higher than those of healthy controls (p<0.001). There was no significant difference between serum values of localized and generalized clinical forms. Study limitations: The main limitation of this present study is the small number of patients with endemic pemphigus and healthy subjects positive for desmoglein 1 antibodies. Conclusions: The increased serum levels of malondialdehyde in patients with chronic active endemic pemphigus foliaceus and healthy subjects from endemic areas with anti-dsg1 antibodies may suggest a contribution of systemic lipid peroxidation in the pathogenesis of endemic pemphigus foliaceus.

Analysis of the reactivity of indirect immunofluorescence in patients with pemphigus foliaceus and pemphigus vulgaris using rat bladder epithelium as a substrate

OBJECTIVES: To evaluate the reactivity of indirect immunofluorescence using rat bladder epithelium as a substrate in patients with pemphigus foliaceus and pemphigus vulgaris from the Department of Dermatology, University of São Paulo Medical School, Brazil. METHODS: Thirty-two patients (8 male and 24 female) from the Department of Dermatology, University of São Paulo Medical School, were selected. Three had mucosal pemphigus vulgaris, 20 had mucocutaneous pemphigus vulgaris, and 9 had pemphigus foliaceus. Patients’ sera were tested by indirect immunofluorescence performed on human foreskin and rat bladder epithelium and by ELISA assays utilizing baculovirus-expressed recombinant desmoglein 3 and desmoglein 1. RESULTS: No patients with mucosal pemphigus vulgaris, 5 of 20 patients with mucocutaneous pemphigus vulgaris (25 percent) and 4 of 9 patients with pemphigus foliaceus (44 percent) had positive indirect immunofluorescence using rat bladder epithelium as a substrate. CONCLUSION: Indirect immunofluorescence using rat bladder epithelium as a substrate is recommended whenever a diagnosis of paraneoplastic pemphigus is considered. The identification of a subset of pemphigus foliaceus and pemphigus vulgaris patients that recognizes desmoplakins by this laboratory tool is critical to avoid the misdiagnosis of paraneoplastic pemphigus.

Evaluation of sensitivity and specificity of enzyme-linked immunosorbent assay (ELISA) for detecting antidesmoglein 1 and 3 in Thai patients with pemphigus vulgaris and foliaceus.

OBJECTIVE: Pemphigus is an acquired autoimmune blistering skin diseases, of which pemphigus vulgaris (PV) and pemphigus foliaceus (PF) are two major subtypes. A novel commercial enzyme-linked immunosorbent assay (ELISA) against Dsg1 and Dsg3 has been well established for diagnosis and prediction of disease activity in PF and PV. At present, the benefit of anti-Dsg 1 and anti-Dsg 3 IgG by ELISA in the diagnosis of pemphigus in Thai patients has never been reported. The objective of the present study is to evaluate the sensitivity and specificity of ELISA for detecting antidesmoglein 1 and 3 in Thai patients with pemphigus. MATERIAL AND METHOD: Retrospective review of anti-Dsg1 and anti-Dsg3 antibody ELISA test results from 48 serum samples collected from 27 patients with PV seven patients with PF and 14 controls. RESULTS: The sensitivity of Dsg1 and Dsg3 ELISA for all patients with PV was 64% and 77.8% respectively. When subgrouped into only PV patients with new diagnosis, the sensitivity of Dsg 1 and Dsg 3 ELISA increased to 85.7% and 100%. In all PF patients, the sensitivity of anti-Dsg 1 ELISA was 71.4% and 100% for newly diagnosed PF cases. Anti-Dsg 3 was not detected in the PF group. The specificity of ELISA for anti-Dsg 1 and anti-Dsg 3 in both types of pemphigus was 85.7% and 92.3% respectively. CONCLUSIONS: Dsg 1 and Dsg 3 ELISA is a simple, highly sensitive and specific test in Thai pemphigus patients with 100% sensitivity in the diagnosis of both new pemphigus vulgaris and foliaceus patients.