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A1564 - Placental Transmogrification of the Lung in a Patient with Anti-Synthetase Syndrome
Author Block: M. M. Khan1, D. S. Zander2, N. Gupta3; 1Pulmonary and Critical Care, University of Cincinnati, Cincinnati, OH, United States, 2Department of Pathology and Laboratory Medicine, University of Cincinnati, cincinnati, OH, United States, 3Pulmonary and Critical care, Univ of Cincinnati, Cincinnati, OH, United States.
Introduction: Placental Transmogrification of the lung (PTL) is a rare histopathological diagnosis, usually diagnosed incidentally. The precise etiology of PTL is not known but it is considered to be a benign lesion and is usually associated with bullous emphysema or pulmonary hamartomas. Case presentation: A 58 year old, African American female, former smoker with a 40 pack per year smoking history, presented to the pulmonary clinic with worsening dyspnea on exertion and chronic cough. Pulmonary function tests showed moderately severe obstructive defect with severely reduced diffusion capacity and she was started on long acting inhaled anticholinergics and inhaled corticosteroids for the management of chronic obstructive pulmonary disease. The patient also complained of worsening muscle weakness, Raynaud’s and scaly skin on the hands. Laboratory evaluation showed elevated creatine kinase and aldolase levels, along with an elevated anti PL-12 antibody. Electromyography and muscle biopsy were consistent with myositis. CT chest revealed severe upper lobe predominant emphysematous disease with a giant left bulla at the apex of left lung measuring 11 cm x 9 cm. Also noticed on the chest CT were increased reticular markings at the bases. Transbronchial cryobiopsy of the lung was performed confirming a non-specific interstitial pneumonia (NSIP) pattern consistent with the diagnosis of Anti-synthetase syndrome. Subsequently, the patient was started on mycophenolate and prednisone for treatment of her underlying interstitial lung disease (ILD). Given persistent symptoms of dyspnea on exertion and exercise limitation despite treatment with immune modulating therapy, the patient was referred to thoracic surgery and underwent video-assisted thoracoscopic surgery guided left bullectomy. Histopathological analysis of the bulla showed papillary structures reminiscent of placental villi extending into the bullous cavity. These villous-like structures contained vascular profiles and fibrotic stroma, characteristic of placental transmogrification of the bulla. The patient continues to do better clinically and is being followed by serial CT imaging and pulmonary function testing. Discussion: PTL was first described in 1979, and since then less than 40 cases have been described in the literature. In a review of 34 cases of PTL, the mean age at presentation was 45.6 years with a male: female ratio of 2.6: 1. It is postulated to be either a histological variant of bullous emphysema, or a possible hamartomatous origin, or a benign proliferation of immature interstitial clear cells with secondary cystic change. To our knowledge, this is the first case of PTL reported in conjunction with pre-existing ILD and anti-synthetase syndrome.