Severe epidermolysis bullosa acquisita in a patient with graft-versus-host disease: causal or coincidental?

ABSTRACT

Graft-versus-host disease (GvHD) is common after haematopoietic cell transplantation (HCT). Mucocutaneous manifestations are variable and may simulate autoimmune bullous dermatoses. However, the association of GvHD with autoimmune disorders, including bullous dermatoses, is also well recognized. We describe a patient with GvHD in whom severe and relapsing epidermolysis bullosa acquisita (EBA) was diagnosed 3 years after transplant and propose a causal association with GvHD. A 66-year-old woman developed GvHD following allogeneic HCT for acute myeloid leukaemia in 2016. This affected her gastrointestinal tract and skin but improved with oral corticosteroids and ciclosporin. In 2019 she presented with a widespread rash consisting of large, tense, haemorrhagic blisters. Histological features were in keeping with EBA. Direct immunofluorescence was also consistent with EBA, demonstrating linear positivity for IgG and C3 confined to the blister base, as was detection of collagen VII antibodies on indirect immunofluorescence. She was admitted and treated with high-dose oral steroids, ciclosporin and intravenous immunoglobulin (IVIg) with eventual resolution of blistering. Although further IVIg administration was planned as an outpatient, this coincided with the start of the COVID-19 pandemic and she elected not to attend and also stopped all medication. Despite this, her EBA remained quiescent until September 2021 when she was readmitted with a severe deterioration in blistering and significant dysphagia due to an oesophageal stricture, with a weight of 31.7 kg. Once again, she responded rapidly to oral prednisolone and IVIg. Dapsone was considered but precluded by G6PD deficiency and there were clinical and adherence concerns about using mycophenolate mofetil. Upon discharge she was again nonadherent to medication and failed to attend for planned IVIg. She flared and was admitted for a third time in December 2021, requiring gastrostomy for nutritional support;her weight at this time was 26.4 kg. Her EBA is currently well controlled on prednisolone and IVIg. EBA is a rare, acquired blistering disorder secondary to autoantibodies targeting type VII collagen. Previous studies have found circulating basement membrane zone (BMZ) antibodies in 24% of chronic GvHD patients, possibly generated in response to chronic BMZ damage (Hofmann SC, Kopp G, Gall C et al. Basement membrane antibodies in sera of haematopoietic cell recipients are associated with graft-versushost disease. J Eur Acad Dermatol Venereol 2010;24 587-94). Corresponding clinical manifestations are rare, with bullous pemphigoid the most frequently reported. EBA is much less common with four previously reported cases [Brassat S, Fleury J, Camus M, et al. (Epidermolysa bullosa acquisita and graftversus- host disease). Ann Dermatol Venereol 2014;141 369-73 (in French)]. As a fifth case of EBA, our patient provides further evidence of a likely pathophysiological relationship between GvHD and autoimmune subepidermal bullous dermatoses, and highlights the significant challenges of managing these vulnerable patient groups during the COVID-19 pandemic.