Pemphigoid diseases: Insights in the nonbullous variant and disease management

Bullous pemphigoid (BP) is a bullous skin disease, mainly occurring at old age. It is characterized by pruritus and blisters on the skin. The disease is caused by an autoimmune response against structural skin proteins BP180 and BP230, causing the epidermis and dermis to split, and thereby blisters to form. Nonbullous pemphigoid (NBP) is a variant of BP that presents with pruritus, but without typical skin blisters. It is unknown why blisters are absent in NBP. In this thesis, we aimed to learn more about the clinical and immunological features of NBP. We noticed that NBP can present with different skin lesions. Red papules and nodules were seen most common. On average, NBP patients were diagnosed after 23 months. The prevalence of pemphigoid in the nursing home population was 6%, and four elderly individuals with pruritus were newly diagnosed with NBP. Interestingly, a low dose of methotrexate was an effective treatment for NBP. Beside these clinical findings, we studied the underlying disease mechanism of NBP. In NBP, immunological reactivity against the BP230 protein was more common than to BP180, while in BP a response against BP180 was more often found. We also studied the presence of IgE antibodies against BP180 and BP230 in the serum and skin of BP and NBP patients, but found no differences. In conclusion, NBP can be a cause of pruritus at old age, and deserves more attention among physicians. Moreover, future research should focus on the underlying disease mechanism of NBP, to explain why blisters are absent.