Technetium-99m-Pyrophosphate Muscle Scintigraphy in Polymyositis: A Case Report

Received 3/11/2005; revised 5/2/2005; accepted 5/4/2005. For correspondence or reprints contact: Yu-Yu Lu, M.D., Department of Nuclear Medicine, Taichung Veterans General Hospital, 160 Section 3, Taichung Harbor Road, Taichung 407, Taiwan. Tel: (886)4-23741349, Fax: (886)4-23741348, E-mail: yuoyuolu@ vghtc.gov.tw Idiopathic inflammatory myopathies represent the largest group of acquired and potentially treatable disorders. Clinical diagnosis is very important but difficult for these disorders. We present a case of 32-year-old woman who suffered from progressive weakness of the proximal muscles since 2003. Clinical presentations and laboratory data showed suspicious diagnosis of polymyositis and muscle biopsy result is compatible with myositis. Her symptoms still fluctuated even under the serial treatment program. However, muscle biopsy is an invasive method, which could not repeat for disease activity. We observe that Tc-pyrophosphate (PYP) muscle scan may be helpful in evaluating the extent of myopathy and disease activity and may be an objective guide for muscle biopsy.