Abstract
Catamenial pneumothorax is one of the most common extra-pelvic presentations of endometriosis, with the gastrointestinal tract being the most common location. Catamenial pneumothorax is defined as spontaneous recurrent pneumothorax occurring in women of reproductive age in a temporal relationship with menses. Symptoms include dyspnea, sharp chest pain, and hypoxemia. A much rarer presentation is the involvement of endometriosis with the diaphragm. In this case, we present a 31-year-old female who presented with signs of pneumothorax. She has had multiple episodes leading to suspicion of catamenial pneumothorax. However, it wasn't until her surgery that the extent of diaphragmatic involvement, characterized by numerous holes secondary to endometriosis, was discovered. She was surgically treated, which led to a drastic improvement in symptoms and a reduction in subsequent episodes. We hope that this case can add to the current limited literature on diaphragmatic endometriosis cases. Since this patient presented with mainly catamenial pneumothorax symptoms, we urge clinicians to still consider diaphragmatic involvement as a primary cause in patients with recurrent episodes of pneumothorax.