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Diffuse alveolar hemorrhage, a rare presentation of polymyositis
Sharoon Samuel1, Brent Brown2, Nita Mason3
1Department of Internal Medicine, University of South Dakota Sanford School of Medicine, USA.
Background:
Diffuse alveolar hemorrhage is a medical emergency caused by persistent and recurrent pulmonary hemorrhage [1]. It is an uncommon presentation of polymyositis. Symptoms of polymyositis include fatigue, muscle pains, proximal muscle weakness, and joint pains [2].
Case Presentation:
A 44-year-old male presented with new onset shortness of breath and productive cough with white sputum and occasional hemoptysis. The patient was diagnosed with diffuse alveolar hemorrhage (DAH) via bronchoscopy and discharged initially on prednisone. The patient's laboratory work indicated positive titers of ANA & anti-Jo-1 antibody with low complement levels. These results pointed towards the diagnosis of polymyositis [3]. DAH can also be caused by systemic lupus erythematosus, Goodpasture's syndrome, Sjogren syndrome, anticoagulant therapy, and antiphospholipid antibody syndrome [4]. However, the possibility of these potential causes was excluded.
Conclusion:
This case of diffuse alveolar hemorrhage was most likely due to polymyositis.
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