Increase of serum copper concentration in Löfgren syndrome.

Chest X ray showing bilateral hilar adenopathies of the mediastinum associated with erythema nodosum suggests the diagnosis of Löfgren syndrome rather than the presence of a lymphoproliferative disorder. However, the occasional finding of high serum levels of copper can induce diagnostic doubts since serum copper increase is an index of lymphoproliferative disorders, particularly of Hodgkin's disease. We observed four patients with Löfgren syndrome presenting with fever, arthralgies, bilateral hilar adenopathies of the mediastinum and erythema nodosum. All patients underwent whole staging for sarcoidosis and serum copper levels were measured. In all cases clinical and instrumental data allowed the diagnosis of sarcoidosis and in all the patients we found high levels of serum copper with an average of 34.8 mumol/L (30.7-39.4) at the onset of the disease. Three months later, the sarcoid process spontaneously remitted and the serum copper levels returned to normal range. Although the finding of an increase of serum copper in patients with mediastinal adenopathies is usually indicative of a lymphoproliferative disorder (Hodgkin's disease), our data suggest that its increase can be related also to non neoplastic adenopathies of the mediastinum, including sarcoidosis.