Pemphigus, polymyositis and myasthenia gravis associated with penicillamine treatment.

Background, D-penicillamine can induce autoimmune disease, particularly in patients with associated immune disorders. Case report, A 67-year old woman who had been taking D-penicillamine for 15 months for rheumatoid arthritis was hospitalized due to the development of a bullous eruption and proximal muscle deficiency. Search for intercellula r antisubstance antibodies in serum was negative. The skin biopsy histology revealed intra-epidermal cleavage in the mucosal body and direct immunoflu orescence revealed epidermal frame-marking with anti-IgG and anti-C-3 antib odies. Other tests revealed muscular cytolysis, and anti-acetylcholine rece ptor antibodies. The electromyogram showed neuromuscular block without musc le deficiency and muscle biopsy showed moderate myositis. D-penicillamine w as interrupted and was followed by cure of the pemphigus and aggravation of the myositis, requiring high-dose systemic corticosteroid therapy. Discussion. This patient developed D-penicillamine induced pemphigus, a rat her frequent observation. The desmogleine immunolabelling favored drug-indu ced pemphigus and the course was rapidly Favorable after withdrawal, Pemphi gus had developed simultaneously with signs of myasthenia and polymyositis. Polymyositis and myasthenia are also known complications of D-penicillamin e therapy. The association of these three complications suggests that D-pen icillamine can unmask certain antigens or have an immunomodulator effect.