Thoracic endometriosis syndrome resembling pulmonary embolism

A 32-year-old infertility patient with a previous diagnosis of stage IV endometriosis experienced shortness of breath and chest pain. She was diagnosed with a pulmonary embolism by spiral volumetric computed tomography (SVCT) and anticoagulated during hospitalization, although no history of thrombosis was ever identified. She continued to have intermittent symptoms of chest pain, back pain, and shortness of breath for the next 1.5 months. Repeat SVCT revealed a large, right-sided pleural effusion with associated consolidation but no evidence of pulmonary embolism. To obtain a definitive diagnosis, a thoracoscopic pleural biopsy was performed and showed thoracic endometriosis involving the pleura. The patient desired to retain her fertility and opted for treatment with depot medroxyprogesterone. She has been asymptomatic for 2 years with this treatment. This case illustrates the importance of recognizing thoracic endometriosis syndrome and the difficulty diagnosing this condition considering its nonspecific features.