CD40LG and systemic lupus erythematosus: The criteria for diagnosis of bullous SLE are as follows: (1) features or diagnosis of SLE based on the American College of Rheumatology (ACR) 2019 criteria; (2) Acutely acquired vesiculobullous rash; (3) Histopathological evidence of subepidermal blisters and dermal infiltrate consisting mostly of neutrophils; (4) Direct immunofluorescence demonstrating deposition of IgG, IgM, or IgA at the basement membrane zone (BMZ); (5) Evidence of antibodies to type VII collagen; (6) Exclusion of other blistering disorders [7].