The cause of diabetic neuropathies has not yet been fully elucidated. In severe forms of proximal diabetic neuropathy, the role of ischaemia caused by inflammatory microvasculopathy has been recently implicated, suggesting the use of anti-inflammatory and immunosuppressive therapeutic agents. We present a 70-year-old man with non-insulin-dependent diabetes mellitus, who developed diabetic amyotrophy responsive to steroids. Pain preceded the development of severe, asymmetric, lower extremities weakness, with amyotrophy, areflexia and fasciculations. Weakness gradually worsened over a 15-month period. The electrophysiologic study revealed predominant motor and axonal polyneuropathies. Laboratory analyses showed elevated erythrocyte sedimentation rate (130/h), moderately elevated cerebrospinal fluid (CSF) protein level and mildly elevated CSF cell content. Therapy with methylprednisolone (120 mg dailu, i.m., with slow tapering) was administered with beneficial effect. Pain subsided immediately after starting the therapy, and strength gradually improved. In conclusion, immunosuppressive treatment should be considered in selected patients with diabetic amyotrophy who develop severe and disabling weakness of the lower extremities.