[Catamenial pneumothorax: an intriguing cause of recurrent pneumothorax in women].

BACKGROUND: Thoracic endometriosis (TE) is one of the causes of secondary pneumothorax in women. According to the literature, 1 in 3 premenopausal women with pneumothorax can be diagnosed with 'catamenial pneumothorax'. The diagnosis is often not or only belatedly made in practice, even though treatment is significantly different than that of primary pneumothorax. CASE DESCRIPTION: A 40-year-old woman came to the emergency department because of dyspnoea and right-sided chest pain. The patient had recurrent pneumothorax and chest pain related to the menstrual cycle. Thoracoscopy revealed thoracic endometriosis. The endometriosis lesions were removed and the patient subsequently received hormonal menstrual suppression treatment. CONCLUSION: In premenopausal women with pneumothorax or a recurrence of pneumothorax, it is important to consider catamenial pneumothorax. Infertility, earlier proven abdominal endometriosis and chest pain linked to menstruation are indications of thoracic endometriosis or catamenial pneumothorax.