Complicaciones pulmonares de las miopatías inflamatorias idiopáticas: a propósito de un caso con miopatía diafragmática

The idiopathic inflammatory myopathies are the largest group of acquired myopathies. On the basis of clinical, histopathological, immunological and demographic features, they can be differentiated into three distinct subsets: dermatomyositis, polymyositis and inclusion-body myositis. Pulmonary involvement is increasingly recognized to be a serious complication and a common cause of morbidity and mortality in these diseases. There are three categories of pulmonary complications in inflammatory myositis: aspiration pneumonia, hypoventilation, and interstitial lung disease. Respiratory failure caused by hypoventilation is considered to be an uncommon complication of inflammatory myositis which occurs in patients with severe generalized muscle weakness and inflammation of inspiratory and expiratory respiratory muscles. Diaphragm weakness is frequent and probably overlooked in inflammatory myopathies. We report the case of a woman with inflammatory myopathy in whom the findings of the diaphragm muscles electromyography demonstrated inflammatory involvement of this muscle.