A service evaluation of the diagnostic testing for mucous membrane pemphigoid in a UK oral medicine unit

Pemphigus vulgaris and mucous membrane pemphigoid: A systematic review of clinical manifestations, diagnosis, and treatment

Pemphigus vulgaris (PV) and mucous membrane pemphigoid (MMP) are mucocutaneous autoimmune diseases characterized by blistering lesions of mucous membranes and skin, with very similar clinical manifestations. This study aimed to systematically review the literature on the clinical and demographic profile, diagnostic methods, and treatment of patients with pemphigus vulgaris (PV) and mucous membrane pemphigoid (MMP). Studies describing cases of PV and MMP diagnosed by direct immunofluorescence that exhibited intraoral manifestations were included. Thirty-two articles were included, with 18 studies on PV and 15 on MMP, corresponding to 50 and 123 cases diagnosed as PV and MMP, respectively. Most patients with PV (64 %) and MMP (81.3 %) were women in the fifth and sixth decade of life, respectively. The mouth was the primary site of involvement both in PV (71.4 %) and in MMP (91 %). The cheek mucosa and gingiva were the most frequently affected intraoral sites in PV (30 %) and MMP (64.2 %), respectively. Direct immunofluorescence was positive for IgG in all cases of the two conditions. The treatment of choice was systemic corticosteroid therapy for patients with PV (50 %) and topical treatment for patients with MMP (53.7 %). Differences in intraoral site predilection, extraoral involvement, and the results of diagnostic tests allow us to trace the clinical, demographic, and diagnostic profile of PV and MMP that contributes to differential diagnosis and therapeutic management.

Optimal biopsy site for the diagnosis of oral pemphigus vulgaris and mucous membrane pemphigoid: a systematic review and meta-analysis

The aim of this study was to critically evaluate the diagnostic yields of direct immunofluorescence (DIF) analysis on perilesional and normal-appearing mucosa biopsy samples, to determine the optimal biopsy site for patients presenting with oral pemphigus vulgaris (PV) or mucous membrane pemphigoid (MMP). Electronic databases and article bibliographies were searched in December 2022. The primary outcome was the rate of DIF positivity. Of 374 records identified after the elimination of duplicates, 21 studies with 1027 samples were ultimately included. Meta-analysis revealed a pooled DIF positivity rate of 99.6% (95% confidence interval (CI) 97.4-100.0%, I2 = 0%) for PV and 92.6% (95% CI 87.9-96.5%, I2 = 44%) for MMP for biopsies from perilesional sites, and of 95.4% (95% CI 88.6-99.5%, I2 = 0%) for PV and 94.1% (95% CI 86.5-99.2%, I2 = 42%) for MMP for biopsies from normal-appearing sites. For MMP, there was no significant difference in the rate of DIF positivity between the two biopsy sites (odds ratio 1.91, 95% CI 0.91-4.01, I2 = 0%). The results suggest that the perilesional mucosa remains the optimal biopsy site for DIF diagnosis of oral PV, while the normal-appearing mucosa biopsy is optimal for oral MMP.

Identification of oral immune disorders- A review and a diagnostic algorithm

Immunological disorders are observed in various clinical presentations in the oral cavity. The pathophysiology of these disorders include but are not limited to primary oral auto-immune disease, systemic disease with oral findings, malignancies, hypersensitivity reactions, drug-induced, and infection-related. Many of these disorders have overlapping oral features, making it difficult for the clinician to diagnose and treat the disorder. There is a need to provide a simple and practical decision-making algorithm to the clinicians and provide them guidance on laboratory investigations. The present review provides a diagnostic algorithm that might minimize outpatient process delays and lead to early management. This is crucial in many cases where oral findings may be the first sign of the disorder, and early treatment can preclude dissemination and complications of the disorder.

Molecular Basis for Global Incidence of Pemphigoid Diseases and Differences in Phenotypes

Pemphigoid (Pg) diseases are a group of potentially fatal autoimmune mucocutaneous diseases. They have different clinical phenotypes, involving only the skin or multiple mucous membranes. They occur globally and frequently affect the elderly. The common marker among all variants is the presence of autoantibodies targeting the dermal-epidermal or mucosal-submucosal junctions, or basement membrane zone (BMZ). Four target antigens in the BMZ were studied. These included BPAG1, BPAG2 and subunits of α6 and β4 human integrins. Our objective was to find a molecular basis for the global incidence of Pg diseases and a mechanism that will explain the vast differences in clinical phenotypes and outcomes. All the variants of Pg that were analyzed had a statistically significant association with HLA-DQβ1*03:01 in ten countries on four continents. This explains the reason for global incidence. Prediction models discovered multiple peptides in each of the four antigens that serve as T cell epitopes. These T cell epitopes were shown to bind to HLA-DQβ1*03:01. In addition, structure modelling demonstrated the peptide-HLA complex bound to the T cell receptor. These autoreactive T cells would stimulate B cells to produce specific anti-BMZ autoantibodies. Anti-BMZ autoantibodies with different specificities will produce different phenotypes, which will account for involvement of different tissues and organs in different molecules. The contribution this study makes is that it provides a molecular basis of why a similar disease occurs in different racial groups. Furthermore, it provides the basis for the production of autoantibodies with different specificities, which resultantly produces different phenotypes.

ELISA detection of anti-desmoglein 1 and anti-desmoglein 3 and indirect immunofluorescence in oral pemphigus: A retrospective study

OBJECTIVE

The aim of this study was to test the efficacy of autoantibodies to desmoglein 1 and desmoglein 3 detected by ELISA and indirect immunofluorescence in the diagnosis of oral pemphigus and to correlate the antibody titres with the severity of the disease.

MATERIALS AND METHODS

We report a retrospective cohort study of 22 patients with oral pemphigus and 64 controls from a single tertiary centre. Data about histopathological examination, direct immunofluorescence, indirect immunofluorescence and ELISA were analysed. Global validation of ELISA and IIF both alone and combined was established by calculating sensitivity, specificity, accuracy and both positive predictive value and negative predictive value. The relationship between Oral Disease Severity Score values and ELISA titres was analysed using Pearson's coefficient.

RESULTS

The best diagnostic performance was observed for anti-desmoglein 3 ELISA. The sensitivity was 75% and specificity 100% and positive predictive value and negative predictive value were 92.5% and accuracy 93.9%. The level of agreement with histopathology + direct immunofluorescence was substantial (k = .758). Anti-desmoglein 3 titres showed a significant correlation with Oral Disease Severity Score (p < .05).

CONCLUSIONS

Serological tests are commonly employed during clinical practice as adjunctive tools. Anti-desmoglein 3 ELISA should be considered as a first-instance diagnostic test for oral pemphigus early detection.