METHODS A 61-year-old man was given short-term thrombolytic treatment with streptokinase (1.5 million IU) 6 hours after the onset of anginal symptoms. Ten days later he complained of severe pain in the right upper arm and right shoulder, and also on the left 3 days later. Simultaneously there occurred severe atrophic pareses of the supra- and infraspinatus, deltoid and rhomboid muscles bilaterally, without sensory component. METHODS When admitted to the neurological department 3 weeks later laboratory tests, immunological parameters, electrophoresis and cerebrospinal fluid were unremarkable. Radiological examinations of the cervical and thoracic vertebrae demonstrated moderate degenerative changes. Computed tomography and magnetic resonance imaging of the cervical vertebrae showed small disc protrusion and narrowing of the intervertebral foramina, but they could not explain the clinical picture. Electromyography demonstrated a bilateral peripheral neurogenic lesion without evidence of radicular distribution or any lesion of individual peripheral nerves. These findings led to the diagnosis of neuralgic amyotrophy (Parsonage-Turner syndrome). METHODS With analgesics and physiotherapy the pareses slowly regressed over the following months. CONCLUSIONS The infusion of streptokinase was the only probable cause found to explain the neuralgic amyotrophy, a connection that has never been reported until now.