Spontaneous pneumomediastinum, pneumothorax and subcutaneous emphysema: Radiological aspects of rare COVID-19 complications in 3 patients.

Spontaneous pneumomediastinum (SPM), pneumothorax (PNX) and subcutaneous emphysema are rare complications of COVID-19 pneumonia. In this paper we describe 3 cases of COVID-19 pneumonia complicated by SPM with or without PNX. Patient 1 was a 56-year-old woman whose medical history was significant for chronic leukemia. She presented with typical clinical signs of COVID-19 pneumonia and after 2 weeks of hospitalization she developed SPM and subcutaneous emphysema. The management of pneumomediastinum (PNM) was conservative and follow-up computed tomography showed resolution of PNM. Patient 2 was a 67-year-old man presenting with fever, cough and dyspnea. Computed tomography pulmonary angiography was performed after 2 weeks of hospitalization and showed bilateral peripheral consolidations together with massive PNM and right-sided PNX. Thoracic drainage catheter was inserted in his right chest. Despite all supportive care, the patient succumbed to illness. Patient 3 was a 74-year-old man who was admitted to our hospital with COVID-19 pneumonia and spontaneous right-sided PNX. A thoracic drainage catheter was inserted immediately and then removed after ten days which has led to progression of subcutaneous emphysema, PNX and newly diagnosed PNM. Patient was carefully monitored for the next 2 weeks. Follow-up chest x-ray showed regression of PNM and PNX. SPM, PNX and subcutaneous emphysema are rare complications of COVID-19 pneumonia. Increased alveolar pressure and diffuse alveolar injury in severe COVID-19 pneumonia may make the alveoli more prone to rupturing which leads to gas dissemination along the peribronchovascular sheath to the mediastinum. Most cases of SPM and PNX resolve with conservative management.