924: A RAGING RIDDLE OF RECURRENT PNEUMOTHORACES

Introduction: Primary spontaneous pneumothorax (PSP) presents in the absence of clinical lung disease. The causes of pneumothorax are numerous and determining the etiology can aid in treatment and prevent recurrence. Description: A middle aged Asian woman with past medical history of iron deficiency anemia secondary to menorrhagia presented with complaints of severe non- productive cough, pleuritic chest pain, menstrual pain, and syncope. CT scan of the chest showed a right sided small to moderate size pneumothorax without parenchymal lung disease. She was discharged home following conservative management and advised to follow up with pulmonary in 10 days. The pneumothorax resolved on follow up CT scans, but reappeared 1 year later as large right hydropneumothorax, requiring ICU admission for acute hypoxic respiratory failure, managed with chest tube placement. She presented with recurrent right pneumothorax a year later. Detailed history revealed the episodes were synchronous with her menstrual cycle. She underwent right sided robotic video assisted thoracoscopic surgery (VATS) with pleurectomy and pleurodesis. Genetic testing for Birt-Hogg-Dubé syndrome was negative. Her menorrhagia was being managed with tranexamic acid. Ultrasound showed bilateral ovarian cysts consistent with endometriomas. She declined hormonal or surgical intervention. Discussion: PSP occurs in 1.2 to 6 per 100,000 women each year with 5% of women under 50 having catamenial pneumothorax (CP). CP is an unusual syndrome of pneumothorax affecting premenopausal women in association with endometriosis. It occurs just prior to or up to 96 hours after the onset of the menstrual period. Diagnosis is based upon a detailed patient history of repeated episodes of pneumothorax in conjunction with the onset of menses. VATS may be required to rule out other conditions and to identify thoracic or pelvic endometriosis or damage to the diaphragm. Cause of CP is unknown. Some women with CP have endometrial tissue on or around the lungs, a condition called thoracic endometriosis while others do not, like in our patient, suggesting other factors may play a role in the development of the disorder. Further studies are needed to explore the pathogenesis of CP to guide management, reduce morbidity and prevent mortality.