[Localization of Ascaris lumbricoides in the thoracic cavity. Report of a case].

Several aspects of the history, evolutive cycle and erratic phases of Ascaris lumbricoides as well as of the symptoms and diagnosis of ascariasis are analyzed. The anatomicophysiological concept of spontaneous pneumothorax and its clinical picture, frequency and treatment are exposed. A patient who underwent thoracic surgery due to an acute respiratory syndrome in who a male Ascaris lumbricoides was surprisingly found obstructing the probe after an explorating left thoracotomy and a resection of the lung apex is presented. The nematode is suggested as the possible etiological agent of the respiratory disease.