In most cases of epidermolysis bullosa acquisita that occur in patients with systemic lupus erythematosus, the diagnosis of systemic lupus erythematosus is made before the development of blistering. We observed three patients with well-documented epidermolysis bullosa acquisita that developed several years before the onset of systemic lupus erythematosus. One patient was producing anti-U1RNP autoantibodies at the time epidermolysis bullosa acquisita was diagnosed, and all five produced this antibody during the systemic lupus erythematosus phase of their illness. In addition, in all five cases of epidermolysis bullosa acquisita with systemic lupus erythematosus antibodies to double-stranded DNA ultimately developed, and severe systemic lupus erythematosus and lupus nephritis developed in four patients. Sera from 15 other patients with epidermolysis bullosa acquisita without overt systemic lupus erythematosus were analyzed for systemic lupus erythematosus-related autoantibodies. Four patients were found to have at least one such autoantibody. These findings further document an association between epidermolysis bullosa acquisita and systemic lupus erythematosus and suggest that patients with systemic lupus erythematosus who present with epidermolysis bullosa acquisita may represent a subset of lupus erythematosus that puts the patient at increased risk for the development of more severe systemic illness. Patients presenting with epidermolysis bullosa acquisita, especially those who are black or Hispanic, should be monitored for the development of potentially life-threatening systemic lupus erythematosus.