Spontaneous Pneumothorax with or Without Pulmonary Cysts in Patients Diagnosed with Covid-19 Pneumonia

Introduction Covid-19 is a recent outbreak of pneumonia caused by severe respiratory syndrome coronavirus (SARS-CoV2). It affects mainly the lungs causing pneumonia and complications like acute respiratory distress syndrome. Computed tomography (CT) plays a key role in diagnosis, the most common findings are bilateral, peripheral and basal ground-glass opacities. Pneumothorax secondary to SARS-CoV2 infection is rare and seems to develop later in the course of the disease, its mechanism is not completely understood. There are several reports about Covid-19 and pneumothorax, but few descriptions associated with pulmonary cysts. We describe seven cases of pneumothorax in patients with Covid-19, some of them with pulmonary cysts. Case descriptions We found a series of seven patients with Covid-19 pneumonia with pneumothorax, some as the initial presentation and some developing after the course of the disease, two to three weeks after initial symptoms. Patients were male, most of them in their fifties, two were former smokers and two had COPD. Only one patient had mechanical ventilation, two of them had pulmonary cysts in the CT scan which were not documented before. A Multifocal upper lobe consolidations. B. 29 days later. Left upper-lobe subpleural cystic lesions, ground-glass opacities, right pneumothorax. Discussion The course of Covid-19 depends on the damage caused by the virus and the host's immune response. CT scan is of great value in diagnosis and monitoring of progression and complications. The most common patterns are ground-glass opacification (88%), peripheral distribution (76%), bilateral (87.5%) and multilobe involvement (78.8%). Pneumothorax or cysts in Covid-19 have been described in few case reports. Pneumothorax seems to occur after two weeks of symptom onset, predominantly in male patients. Liu et al. described a series of two men with pneumothorax and peripheral pulmonary cysts after 26 and 40 days of symptom onset;cysts decreased in number and size in subsequent images. Other reports have described cysts or bullae. Pneumothorax seems to develop later in the course of the disease and they are most likely related to the reparation process. Mechanical ventilation with positive pressure is not associated with all cases. The pathogenesis of pulmonary cysts formation in Covid-19 is not well understood. Proposed mechanisms of cystic lung disease include necrosis due to ischemia, remodeling of interstitial matrix, and bronchial obstruction with distal overinflation phenomenon. Information regarding mechanism of pneumothorax in patients with lung infection secondary to Covid-19 is not yet completely understood, but cysts formation may play a role.