Mucocutaenous bullous pemphigoid

Clinical variant of (classic) bullous pemphigoid with involvement of 1 to a maximum of 3 mucosal sites (oral/genital/nasal mucosa), which is characterized by frequent palmoplantar involvement, as well as the absence of anti-BP230 antibodies (see pemphigoid antibodies below) and peripheral eosinophilia (Kridin K et al. 2019).

Bullous pemphigoid (BP) is a globally prevalent subepidermal blistering autoimmune disease that is associated with a significant morbidity and mortality rate. Bullous pemphigoid is characterized by a very itchy bullous, sometimes urticarial exanthema that mainly affects the flexures of the limbs and the abdomen. In many cases, extensive erosions are also detectable. About 20% of BP patients show neither obvious blisters nor erosions at the beginning. Instead, atypical manifestations occur (Amber KT et al. 2018), such as pruritic, urticarial, eczematous, dyshidrotic or mucocutaneous lesions.

m:w=1:1.8 /in BP without mucosal involvement - m:w= 1:1

The average age is 79.1 years

Bullous pemphigoid (BP) is a globally prevalent subepidermal blistering autoimmune disease that is associated with a significant morbidity and mortality rate. Bullous pemphigoid is characterized by a highly pruritic bullous, sometimes urticarial, exanthema that mainly affects the flexures of the limbs and the abdomen. Pruriginous, urticarial, eczematous, dyshidrotic or preferably mucocutaneous lesions may characterize the clinical picture.

In a larger study (n= 273 patients with BP), the oral mucosa was the most frequently affected mucosal surface (71.0%), followed by the genital mucosa (25.8%), the nasal mucosa (22.6%), the anal mucosa (12.9%) and the laryngeal mucosa (4.9%). >than 3 mucosal areas are not affected. In patients with oral lesions, the most affected oral structures were the buccal mucosa (55.6%) and the soft palate (53.3%). Isolated genital or nasal involvement was found in about 30% of patients. Monotopic involvement can make clinical diagnosis more difficult.

Compared to classic BP patients, patients with mucocutaneous pemphigoid have more palmoplantar involvement (67.7 % vs. 37.2 %), a lower seropositivity rate (18.2 % vs. 54.2 %), lower levels (29.3 ± 64.5 vs. 129.5 ± 304.4 U/ml) of anti-BP230 autoantibodies and reduced peripheral eosinophil counts (760.0 ± 638.6 vs. 1296.3 ± 1013.7) (Ständer S et al. 2021).

Compared to classic BP patients, patients with mucocutaneous BP were younger (71.8 years vs. 79.3 years), had lower peripheral eosinophilia (17.8 % vs. 41.9 %), were treated with higher doses of corticosteroids (prednisone > 1 mg/kg: 67.9 % vs. 51.8 %) and showed reduced anti-BP230 positivity (18.2 % vs. 54.2 %). Patients with mucosal involvement were more likely to have palmo-plantar involvement (67.7% vs. 37.2%) (Ständer S et al. 2021).

If mucosal lesions predominate in a pemphigoid disease, it is by definition a "mucosal pemphigoid" (Ständer S et al. 2021).

1. Amber KT et al. (2018) Autoimmune subepidermal bullous diseases of the skin and mucosae: Clinical features, diagnosis, and management. Clin Rev Allergy Immunol 54: 26-51
2. Clapé A et al. (2018) Mucosal involvement in bullous pemphigoid is mostly associated with disease severity and to absence of anti-BP230 autoantibody. Front Immunol 9:479.
3. della Torre R et al. (2012) Clinical presentation and diagnostic delay in bullous pemphigoid: a prospective nationwide cohort. Br J Dermatol 167:1111-1117.
4. Kridin K et al (2019) Assessment of the Prevalence of Mucosal Involvement in Bullous Pemphigoid. JAMA Dermatol 155:166-171.
5. Schmidt E et al. (2012) Clinical features and practical diagnosis of bullous pemphigoid. Immunol Allergy Clin North Am 32:217-232.
6. Ständer S et al. (2021) Immunological features and factors associated with mucocutaneous bullous pemphigoid - a retrospective cohort study. J Dtsch Dermatol Ges 19:1289-1295.