Catamenial Pneumothorax: A Challenging Diagnosis

Abstract

Catamenial pneumothorax is the most frequent manifestation of thoracic endometriosis. Diagnosis should be suspected if a spontaneous pneumothorax occurs within 72 hours from the onset of menstrual bleeding. Furthermore diagnosis can be supported by the macroscopic findings within the pleural cavity, generally represented by multiple nodules with color ranging from brown to violet and of variable dimension (from several micrometers to 1 cm); confirmation comes from histologic examination of the resected specimens (endometrial glands surrounded by a decidual-like stroma). Increased levels of CA 125 and CA 19-9 are useful clues. On the other hand, diagnosis of catamenial pneumothorax can be challenging in atypical cases presenting with none of the above mentioned features. We report a similar case in which no proof of endometriosis was found neither at intraoperative examination of the affected hemithorax, nor at gynecological evaluation; moreover laboratory parameters and CA 125 and CA 19-9 in particular were within normal values. Eventually, diagnosis of catamenial pneumothorax was formulated only when a temporal connection with menstrual bleeding was noticedand when, on the ex juvantibus principle, implementation of a specific medical treatment was able to prevent further recurrences of the disease. A gonadotropin releasing hormone (GnRH) analogue therapy was establishedand since then, after a two years follow-up, pneumothorax had never recurred. In conclusion, diagnosis of catamenial pneumothorax could be established on clinical grounds only.

Thoracic Endometriosis and Spontaneous Pneumothorax

“…La mayoría de las teorías que tratan de describir este diagnóstico clínico, sugieren la presencia de un diafragma debilitado debido a defectos en éste o un parénquima pulmonar debilitado debido a cambios hormonales, lo que promueven un ambiente adecuado para el paso de implantes endometriales ectópicos al diafragma. El tejido implantado, debido a su sensibilidad a los estímulos hormonales de los ovarios, sangra simultáneamente al endometrio normal en cada ciclo menstrual ocasionando neumotórax recurrente durante la menstruación (5,6) .…”

“…Varios tratamientos hormonales han sido utilizados después de la cirugía para disminuir el riesgo de recurrencia incluyendo terapias anticonceptivas orales, dispositivos intrauterinos, danazol y progestinas (6) . La endometriosis pleural generalmente se presenta con múltiples implantes que pueden variar desde varios micrómetros hasta 1 cm; su color puede variar de marrón a violeta, según el período del ciclo menstrual (5) .…”

“…Hasta la fecha, todavía hay una falta de consenso sobre el diagnóstico y el tratamiento óptimo de esta condición. De hecho, debido a su rareza, solo los informes de casos o estudios retrospectivos están disponibles sobre este tema en la literatura existente (5) .…”