Intravenous immunoglobulins for rituximab-resistant mucous membrane pemphigoid

A systematic review on efficacy, safety and treatment durability of intravenous immunoglobulin in autoimmune bullous dermatoses: Special focus on indication and combination therapy

Autoimmune bullous diseases (AIBDs) are a group of rare blistering dermatoses of the mucous membrane and/or skin. The efficacy, safety and treatment durability of intravenous immunoglobulin (IVIg) as an alternative treatment should be explored to systematically review the available literature regarding treatment outcomes with IVIg in AIBD patients. The predefined search strategy was incorporated into the following database, MEDLINE/PubMed, Embase, Scopus and Web of Science on 18 July 2022. Sixty studies were enrolled using Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines. The use of IVIg alone or combined with rituximab was reported in 500 patients with pemphigus, 82 patients with bullous pemphigoid, 146 patients with mucous membranes pemphigoid and 19 patients with epidermolysis bullosa acquisita. Disease remission with IVIg therapy and RTX + IVIg combination therapy were recorded as 82.8% and 86.7% in pemphigus, 88.0% and 100% in bullous pemphigoid and 91.3% and 75.0% in mucous membrane pemphigoid, respectively. In epidermolysis bullosa acquisita, treatment with IVIg led to 78.6% disease remission; no data were available regarding the treatment with RTX + IVIg in this group of patients. Among all the included patients, 37.5% experienced at least one IVIg-related side effect; the most common ones were headaches, fever/chills and nausea/vomiting. The use of IVIg with or without rituximab had a favourable clinical response in patients with AIBDs. IVIg has no major influence on the normal immune system, which makes its utilization for patients with AIBDs reasonable.

Ocular mucous membrane pemphigoid: novel treatment strategies

PURPOSE OF REVIEW

To describe current treatments of ocular mucous membrane pemphigoid (OMMP), including conventional systemic immunosuppression (CIST) and novel biologic agents.

RECENT FINDINGS

CIST remains the main stay therapy for the management of OMMP. The choice of agents is tailored to disease severity - mild disease is treated with dapsone, whereas moderately severe cases are often treated with mycophenolate mofetil or sulfa-based drugs and severe cases are treated with cyclophosphamide. In recalcitrant disease newer biologics such as Rituximab, intravenous immunoglobins and tumour necrosis alpha antagonists have proven to be effective in disease control. Control of inflammation with topical therapy and halting conjunctival fibrosis remain as areas of unmet clinical needs.

SUMMARY

OMMP is largely treated with CIST. The recent introduction of new biologic agents could shape the way the disease is treated in the near future.

Laryngeal mucous membrane pemphigoid serves as a prognostic factor for poor response to treatment with rituximab

Mucous membrane pemphigoid (MMP) is an autoimmune blistering, scarring and occasionally mutilating disease that may progress to blindness or airway obstruction. Over the past few years, rituximab (RTX) has emerged as a potential therapeutic solution for MMP; however, the literature regarding its efficacy in the treatment of severe MMP is sparse. We studied four patients with recalcitrant MMP who were treated with RTX. Three of these had recalcitrant laryngeal disease; two were unresponsive to RTX, while the third patient achieved complete remission (CR) but relapsed twice. The fourth patient, who had oral and ocular disease, also achieved CR. In addition, we reviewed 143 cases of MMP treated with RTX reported in the literature to date. Of these, 120 had late observation endpoints, of whom 81 (67.5%) achieved CR, 24 (20%) received partial remission and 15 (12.5%) had no remission. Based on this study, the presence of laryngeal MMP seems to predict refractoriness to RTX treatment. In conclusion, we found that RTX can ameliorate the MMP course and that laryngeal involvement, which is known to be a prognostic factor for severe MMP, may also predict poor response to RTX.

Diagnosis of Autoimmune Blistering Diseases

Autoimmune skin blistering diseases (AIBD) are characterized by autoantibodies that are directed against structural proteins in the skin and adjacent mucous membranes. Some clinical signs are typical for a specific AIBD, however, correct diagnosis requires the detection of tissue-bound or circulating autoantibodies. The gold standard for diagnosis of AIBD is the detection of autoantibodies or complement component 3 by direct immunofluorescence (DIF) microscopy of a perilesional biopsy. Circulating antibodies can be detected via indirect immunofluorescence (IIF) microscopy of different tissue substrates including human skin, monkey esophagus, and more recently, recombinant forms of the different target antigens. Latter are also employed in various commercial ELISA systems and by immunoblotting in in-house assays available in specialized laboratories. ELISA systems are also particularly valuable for monitoring of the disease activity during the disease course which can be helpful for treatment decisions. Exact diagnosis is essential for both treatment and prognosis, since some AIBD are associated with malign tumors such as paraneoplastic pemphigus and anti-laminin 332 mucous membrane pemphigoid. This review presents clinical and immunopathological features of AIBD for the state-of the art diagnosis of these disorders.