Decreased Muscle Strength, Type 2 Respiratory Failure, Heart Failure, Positive Anti-mitochondrial Antibodies—Rare Atypical Manifestations of Inflammatory Myopathy

An elderly woman with a chronic course of disease presented with progressive weakness of lower limbs, heart failure, carbon dioxide retention, periorbital pigmentation, increased hair around the eyebrows, as well as multiple positive autoantibodies. After multidisciplinary team discussion, restrictive ventilatory dysfunction caused by significantly decreased diaphragm movement was taken as a breakthrough to sort out the etiology step by step. Based on clinical manifestations, serological and imaging features, as well as immunohistochemical staining of quadriceps femoris pathological complement, the final diagnosis of inflammatory myopathy associated with anti-mitochondrial antibodies was established. After correcting heart failure, intermittent non-invasive ventilation and rehabilitation training, clinical symptoms and functional status of the patient were significantly improved. The joint participation of the multidisciplinary team to identify the causes and solve problems in diagnosis and treatment decision-making reflects the great significance of multidisciplinary collaboration in rare diseases.