HLA genotype, clinical and immunofluorescence findings of 30 patients with type VII collagen antibody positive subepidermal bullous disease

Epidermolysis bullosa acquisita (EBA) and mucous membrane pemphigoid are mucocutaneous blistering disorders that are associated with antibodies that target type VII collagen (anti-col7). There are relatively few studies that closely investigate the clinical phenotype and HLA genotype of patients who are anti-col7 positive. We therefore characterized all patients with anti-col7-positive subepidermal bullous disease that were treated at our centre. In total, 30 patients were identified, 29 had mechanobullous skin lesions and all had oral ulceration. The most common sites for oral lesions were the tongue, lip and palatal mucosa. Laryngeal and oesophageal lesions were seen in five and six patients, respectively. Oesophageal involvement was associated with erosions and stricture formation in the cervical or thoracic oesophagus and the majority of patients with oesophageal involvement had concomitant bullous pemphigoid180/230 antibodies and were of Black African ancestry. IgA deposition on direct immunofluorescence was associated with lower age at disease onset but did not correlate with clinical features or autoantibody profiles. Concomitant BP180/230 antibody positivity was associated with earlier disease onset and Black African ancestry. HLA genotyping was performed in 18 patients and demonstrated HLA-DQB1*03 and HLA-DQB1*06 alleles were most commonly associated with anti-col7 EBA. HLA genotype did not, however, correlate with clinical features of autoantibody profiles. Taken together, this study demonstrates that concomitant BP180/230 and anti-col7 antibodies are associated with earlier disease onset, Black African ancestry and potentially oesophageal involvement.