The clinical similarity between Addison's disease and the syndrome recognized as dermatomyositis with scleroderma may be marked. Confusion regarding the differential diagnosis is likely and has been discussed by Osler,1Winfield,2Boardman,3Longcope,4Rowntree and Snell,5Brown and his associates,6Howard7and others. The coexistence of these two diseases must be extremely uncommon, and the contemporary literature contains few reliable reports. Lewin and Heller8in a review of 508 cases of scleroderma reported before 1895 noted that the dual diagnosis had been made in only 4. Osier1reviewed these cases and did not consider that any of the patients had Addison's disease. In 1908 Lichtwitz9reported a single case in which the two diseases coexisted clinically; the observation was confirmed at autopsy. Recently Leriche, Jung and De Bakey10reported the occurrence of Addison's disease in a patient under treatment for scleroderma. Autopsy was not performed, however, and