Abstract
A patient with Wilson disease, under prolonged treatment with penicillamine, developed lesions of elastosis perforans serpiginosa (EPS). Examination of biopsy specimens by light microscopy revealed the characteristic changes of EPS. Examination by transmission electron microscopy revealed structural changes in the elastic fibers not previously described. The appearance of the lesions by scanning electron microscopy is described for the first time. Penicillamine induced EPS may be morphologically distinct from the idiopathic form.