Catamenial pneumothorax

Catamenial pneumothorax is a condition of collapsed lung occurring in conjunction with menstrual periods (catamenial refers to menstruation), believed to be caused primarily by endometriosis of the pleura (the membrane surrounding the lung)Definition from mercksource.com (Dorlands Medical Dictionary).

Classification

Catamenial Pneumothorax is the most common form of thoracic endometriosis syndrome, which also includes catamenial hemothorax, catamenial hemoptysis and endometriosis lung nodules, as well as some exceptional presentations.

Symptoms and signs

Onset of lung collapse is less than 72 hours after menstruation. Typically, it occurs in women aged 30-40 years (and exclusively in women of menstrual age) with a history of pelvic endometriosis.

Pathophysiology

Endometriosis can attach to the lung, forming chocolate-like cysts. Generally the parietal pleura is involved, but the lung itself, the visceral layer, the diaphragm, and more rarely the tracheobronchial tree may also be afflictedJoseph J, Sahn SA. Thoracic endometriosis syndrome: new observations from an analysis of 110 cases. Am J Med 1996; 100: 164-70. PMID 8629650 . How this endometrial tissue reaches the thorax remains enigmatic, although defects in the diaphragm can often be foundAlifano M, Roth T, Broet SC, Schussler O, Magdeleinat P, Regnard JF. Catamenial pneumothorax: a prospective study. Chest 2003; 124: 1004-8. PMID 12970030.

The cysts can release blood; the endometrial cyst "menstruates" in the lung. Air can move in by an unknown mechanism. The blood and air cause the lung to collapse (i.e. catamenial hemopneumothorax)Glynis D. Wallace. Living With Lung And Colon Endometriosis: Catamenial Pneumothorax. Authorhouse, 2005. ISBN 1420883313.

Diagnosis

Diagnosis can be hinted by high recurrence rates of lung collapse in a woman of reproductive age with endometriosis. Nowadays, video-assisted thoracoscopy is used for confirmation.

Treatment

Pneumothorax is a medical emergency because it comes with severe pain and decreased lung function. A chest tube should be inserted after clinical assessment. This releases the air and menstrual blood, and the lung can re-expand.

Surgery, hormonal treatments and combined approaches have all been proposed, with variable results in terms of short and long term outcome. Surgical removal of the endometrial tissue should be endeavoured during menstruation for optimal visualisation of the cystPoyraz AS, Kilic D, Hatipoglu A, Demirhan BA. A very rare entity: catamenial pneumothorax. Asian Cardiovasc Thorac Ann 2005; 13:271-3. PMID 16113003. Pleurodesis may also be helpful. Menstruation and accompanying lung collapse can be suppressed with hormone therapy, like with danazol or oral contraceptives.

Epidemiology

Some sources claim this entity represents 3-6% of pneumothorax in women. In regard of the low incidence of (primary spontaneous, i.e. not due to surgical trauma etc.) pneumothorax in women (about 1/100'000/year), this is a very rare condition. Hence, many basic textbooks don't mention it, and many doctors have never heard of itGlynis D. Wallace. Living With Lung And Colon Endometriosis: Catamenial Pneumothorax. Authorhouse, 2005. ISBN 1420883313. However, catamenial pneumothorax is probably under-recognisedAlifano M, Roth T, Broet SC, Schussler O, Magdeleinat P, Regnard JF. Catamenial pneumothorax: a prospective study. Chest 2003; 124: 1004-8. PMID 12970030.

References

Review article: Alifano M, Trisolini R, Cancellieri A, Regnard JF. Thoracic endometriosis: current knowledge. Ann Thorac Surg 2006; 81: 761-9. PMID 16427904

Gynecology | Medical emergencies | Menstruation | Pulmonology | Rare diseases