Blistering diseases in the mature patient

Comprehensive review on the pathophysiology, clinical variants and management of pemphigus (Review)

Pemphigus represents a group of chronic inflammatory disorders characterized by autoantibodies that target components of desmosomes, leading to the loss of intercellular adhesion between keratinocytes and causing intraepithelial blistering. The pemphigus group consists of four main clinical types with several variants: pemphigus vulgaris (with pemphigus vegetans and pemphigus herpetiformis as variants), pemphigus foliaceus, paraneoplastic pemphigus and IgA pemphigus (with two clinical variants: intraepidermal neutrophilic IgA dermatosis and subcorneal pustular dermatosis). Genetic factors are involved in the pathogenesis, with HLA-DR4 (DRB1*0402) and HLA-DRw6 (DQB1*0503) allele more common in patients with pemphigus vulgaris, HLA class II DRB1*0344 and HLA Cw*1445 correlated with paraneoplastic pemphigus, and HLA-DRB1*04:01, HLA-DRB1*04:06, HLA-DRB1*01:01, HLA-DRB1*14, associated with a higher risk of developing pemphigus foliaceus. Autoantibodies are conducted against structural desmosomal proteins in the skin and mucous membranes, mainly desmogleins, desmocollins and plakins. Cell-mediated immunity may also play a role, especially in paraneoplastic pemphigus. Patients may present erythema, blisters, erosions, and ulcers that may affect the skin, as well as mucosal surfaces of the oral cavity, eyes, nose, leading to severe complaints including pain, dysphagia, and fetor. Oral mucosal postbullous erosive lesions are frequently the first sign of disease in pemphigus vulgaris and in paraneoplastic pemphigus, without skin involvement, making the diagnosis difficult. Treatment options classically include immunosuppressive agents, such as corticosteroids and corticosteroid-sparing agents such as azathioprine, mycophenolate mofetil, cyclophosphamide, methotrexate or dapsone. Newer therapies focus on blocking cell signaling events induced by pathogenic autoantibodies and/or targeting specific autoantibodies. The disease evolution is conditioned by the treatment with maximum doses of corticosteroids and the side effects associated with long-term immunosuppressive therapy, which is why patients need a multidisciplinary approach in following the treatment. In this review, we provide a comprehensive overview of the epidemiology, pathophysiology, clinical aspect, diagnosis and management of the main intraepidermal blistering diseases from the pemphigus group.

The association between clinical and laboratory findings of bullous pemphigoid and dipeptidyl peptidase-4 inhibitors in the elderly: a retrospective study

Aim

To evaluate the association between the use of dipeptidyl peptidase-4 inhibitors (DPP4I) and clinical and laboratory findings of bullous pemphigoid (BP) in patients treated at the European Reference Network – Skin Reference Centre in Croatia.

Methods

This retrospective study enrolled 82 patients treated for BP at the Department of Dermatovenereology, University Hospital Center Zagreb from January 2015 to December 2019. Clinical features of BP, presence of comorbidities, and laboratory findings of anti-BP antibodies and eosinophilia were analyzed in three groups of BP patients: 1) diabetes mellitus (DM) type II patients treated with DPP4I, 2) DM type II patients not treated with DPP4I, and 3) non-DM type II patients.

Results

The average age and anti-BP180 titer were similar in all three groups. DPP4I group had a slightly lower eosinophil level in both peripheral blood (4.89%) and biopsy specimens (87.5%), but the difference was not significant. The prevalence of inflammatory BP in DPP4I group was 76.5%. DPP4I group had significantly higher percentage of patients with chronic renal failure and dementia (52.9% and 11.8%, respectively) compared with non-DPP4I DM (14.3% and 0%, respectively) and non-DM type II patients (15.7% and 0%, respectively).

Conclusion

BP patients treated with DPP4I and those not treated with DPP4Is did not significantly differ in laboratory findings. However, DPP4I treatment was associated with an inflammatory subtype of BP and a higher prevalence of dementia and chronic renal failure. These findings warrant further research into the association of BP and DM with dementia and chronic renal failure.