Background Inflammatory muscle diseases commonly present with proximal myopathy. However, important differential diagnoses include muscular dystrophy and metabolic myopathy.
Objectives To study the clinical profile of inflammatory muscle disease in our patients and to compare the clinical and histopathological diagnosis in these patients.
Methods A retrospective study of 25 patients who presented to Rheumatology unit, UMMC from January 2007 to September 2011 with the clinical diagnosis of possible inflammatory myopathy was done. All had muscle biopsy done.
Results Mean age was 53.3 years. Of the 25 patients, 17(68%) had diagnosis based on clinical presentation. 16(64%) had diagnosis based on muscle biopsy in which 9(36%) had the histopathological diagnosis of dermatomyositis, 3(12%)polymyositis, 2(8%)muscular dystrophy, 1(4%)inclusion body myositis (IBM) and 1(4%) metabolic myopathy. The remainder 9(36%) had inconclusive histopathological diagnosis. Significant correlation (p=0.01) was seen between clinical diagnosis and the histopathological diagnosis. Final diagnosis of dermatomyositis was made in 11(44%) patients, amyopathic dermatomyositis 2(8%), polymyositis 5(20%), Becker’s muscular dystrophy 2(8%),MCTD 2(8%) and 1(4%) each for IBM, fibromyalgia, and metabolic myopathy. 19 patients had inflammatory myositis conclusively.
The most common clinical presentation was proximal myopathy (23, 92%), followed by muscle pain (13, 52%). Raised serum creatinine kinase was seen in all patients and 21(84%) had transaminitis. 18(72%) had positive ANA titre. ENA was positive in 7(28%) out of which 4 were anti-Jo-1 positive. 88% received corticosteroids and 72% received immunosuppressive agents. 9(36%) attained clinical remission.
Conclusions Diagnosis of muscular pathologies through muscle biopsies significantly correlated with our clinical diagnosis. Dermatomyositis is the prominent inflammatory muscle disease.
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Disclosure of Interest None Declared
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