A chronic autoimmune subepidermal bullous disease characterized by grouped pruritic lesions such as papules, urticarial plaques, erythema, and herpetiform vesiculae, with a predominantly symmetrical distribution on extensor surfaces of the elbows (90%), knees (30%), shoulders, buttocks, sacral region, and face of children and adults. Erosions, excoriations and hyperpigmentation usually follow. It may also appear as a consequence of gluten intolerance.

A reduction in the level of performance of the kidneys in areas of function comprising the concentration of urine, removal of wastes, the maintenance of electrolyte balance, homeostasis of blood pressure, and calcium metabolism.