ABSTRACT
Idiopathic inflammatory myopathies are a heterogeneous group of autoimmune disorders along with muscle weakness. Pulmonary involvement is one of the main causes of mortality and morbidity. Our case has been diagnosed as dermatomyositis. She was referred to our clinic with the complaint of dyspnea. Radiography, diffusion and pulmonary function tests were normal. Ground glass opacities were detected in High Resolution Computarise Tomography (HRCT) of patient but patient was in the early period of interstitial lung disease. With the complaint of air hunger, respiratory muscle weakness was considered and Maximal İnspiratuar Pressure (MIP), Maximal Exspiratuar Pressure (MEP) are planned and measured 34% and 39% respectively. Ciyclophospamide was added to patient’s steroid therapy. After two months of treatment, regression of ground glass opacities were detected and values of MIP and MEP were measured 92% and 94% respectively. It should be considered that respiratory function tests and chest radiographies could be insufficient in diagnosing respiratory muscle weakness and interstitial lung disease. In suspected cases HRCT should be taken and MIP, MEP should be measured. Measurement of MIP and MEP are parameters that can be used in diagnosis and response to treatment of respiratory muscle weakness.