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A3215 - A Dilemma in the Etiology for Serositis
Author Block: M. Krishnan1, N. Jagan2, Z. S. DePew2; 1Internal medicine, Creighton University, Omaha, NE, United States, 2Pulmonary and critical care medicine, Creighton University, Omaha, NE, United States.
Introduction Autoimmunity in mesothelioma is yet to be established. There have been studies linking asbestos exposure and systemic autoimmune phenomenon with no clear underlying disease process. Herein we present a case of an elderly male with recurrent pleural effusion, negative asbestos exposure, and positive serologies suggestive of systemic lupus erythematosus (SLE) with no other distinguishing clinical features of SLE, who underwent further evaluation to determine an alternative etiology. Case description A 75-year-old Caucasian male with past medical history significant for hypertension presented to clinic for evaluation of dyspnea. He had progressive dyspnea for the preceding month leading to severe restriction of activity. Associated symptom included only a minimally productive cough. Review of systems was negative for weight loss, recent travel or fever. He denied smoking and occupational history was negative for exposure to asbestos, silica or other environmental pathogens. Physical examination revealed decreased breath sounds throughout the right hemithorax. He was further evaluated with a chest radiograph which showed a large right-sided pleural effusion. He underwent thoracentesis with removal of 3 Liters of sero-sanguinous pleural fluid. Pleural fluid was exudative in nature with macrophage predominance. Pleural fluid gram stain, culture and cytology were negative. Further work up was done to establish the underlying etiology for the new-onset unilateral pleural effusion. Laboratory studies showed a positive ANA, ds-DNA and RF. He denied any symptoms suggestive of rheumatologic illness such as rash, oral ulcers or arthralgias. A rheumatology consult was obtained in view of positive serologic findings and he was started on empiric prednisone therapy. The patient continued to have dyspnea and re-accumulation of the pleural effusion. A repeat thoracentesis was performed and repeat cytology was again negative for malignancy. At this time, a CT scan of the chest was obtained which revealed right-sided irregular pleural-based masses. Subsequent parietal pleural biopsy via medical thoracoscopy confirmed epithelioid mesothelioma. Discussion Occupational exposure to asbestos has been linked to positive autoimmune serologic testing, such as ANA, but a clear link to specific disease has not been established. Our case is unique in that our patient had no history of prior asbestos exposure to explain the above findings. There have been previous reports of serositis from autoimmune causes, resistant to treatment, which on further investigation have been diagnosed to have mesothelioma. It is important to recognize falsely positive serologic autoimmune testing and further investigate for underlying mesothelioma in the context of recurrent serositis.