What is the treatment for catamenial pneumothorax?

Treatment of Catamenial Pneumothorax

The optimal treatment for catamenial pneumothorax requires a multidisciplinary approach including both surgical intervention via video-assisted thoracoscopic surgery (VATS) and hormonal therapy to achieve ovarian rest in the postoperative period. 1

Definition and Clinical Presentation

• Catamenial pneumothorax is defined as recurrent spontaneous pneumothorax occurring within 72 hours before or after menstruation in women of reproductive age 1
• It is typically right-sided (85-95% of cases) and has a heightened tendency to recur coinciding with the menstrual cycle 1, 2
• Despite being considered relatively rare, it accounts for up to 25-30% of spontaneous pneumothoraces in women undergoing surgical treatment for recurrent pneumothorax 1, 2
• The typical presentation includes chest pain, dyspnea, and sometimes hemoptysis occurring around menstruation 1

Pathophysiology

• Catamenial pneumothorax is associated with thoracic endometriosis and often with a history of pelvic endometriosis (found in 30-51% of cases) 1, 2
• Inspection of the pleural diaphragmatic surface during thoracoscopy typically reveals defects (fenestrations) and/or small endometrial deposits 1
• The most accepted theory explains catamenial pneumothorax as aspiration of air from the abdomen and genital tract via diaphragmatic fenestrations 1
• An alternative mechanism involves erosion of the visceral pleura by endometriosis deposits found on the pleural surface 1

Diagnostic Approach

• Catamenial pneumothorax should be suspected in any female patient with recurrent pneumothoraces, particularly if right-sided and temporally related to menstruation 1
• Thoracoscopy is essential for diagnosis, revealing characteristic findings such as diaphragmatic defects and endometrial deposits 2, 3
• Careful inspection of the diaphragmatic surface during VATS is crucial, as "blueberry spots" or fenestrations may be present 4

Treatment Algorithm

Surgical Management

1. Video-assisted thoracoscopic surgery (VATS) is the first-line surgical approach 1, 3
   • Identification and repair of diaphragmatic defects/fenestrations 2, 3
   • Resection of visible endometriosis-related lesions 5, 3
   • Covering diaphragmatic defects with mesh (e.g., polytetrafluoroethylene) in cases with pores or fenestrations 3
   • Pleurodesis (chemical or mechanical) or pleurectomy to prevent recurrence 2, 3
   • Resection of any abnormal lung parenchyma (blebs, bullae, or hemorrhagic/emphysematous areas) 2

Hormonal Therapy

• Postoperative hormonal therapy is essential to suppress ovulation and prevent recurrence 1, 6
• Gonadotropin-releasing hormone (GnRH) analogues are commonly used for 6-12 months postoperatively 2, 3
• Hormonal therapy aims to achieve ovarian rest and prevent cyclical endometrial proliferation 1

Multidisciplinary Management

• Treatment should involve thoracic surgeons, pulmonologists, and gynecologists 6, 5
• Early diagnosis and combined surgical-hormonal approach is crucial for successful outcomes 6, 5
• Long-term follow-up is recommended due to the risk of recurrence 5, 3

Recurrence Prevention

• The combination of VATS with diaphragmatic repair, pleurodesis/pleurectomy, and postoperative hormonal therapy provides the best outcomes 3
• Recurrence rates without this combined approach can be as high as 30% 5
• Chemical pleurodesis may be used as an adjunct to surgical treatment to further reduce recurrence risk 4

Pitfalls and Caveats

• Failure to inspect the diaphragm thoroughly during surgery may miss critical defects 3, 4
• Omitting postoperative hormonal therapy significantly increases recurrence risk 2, 3
• Catamenial pneumothorax should be suspected in all women of reproductive age with recurrent pneumothorax, even without symptoms of pelvic endometriosis 4
• Delaying multidisciplinary management may lead to repeated episodes and increased morbidity 6, 5