RESUMEN
Little is known about the light phenotype of SARS-CoV-2 pneumonia, which behaves in an unusual way, unlike other known respiratory diseases. We believe that the histopathological features of early COVID-19 could be considered the pathophysiological hallmark of this disease. Lung cryobiopsies show almost pristine alveoli, enlarged/hyperplasic alveolar capillaries along with dilatation of the post capillary pulmonary venules. Hypoxemia could therefore be explained by a reduction of the normal V/Q ratio, due to blood overflow around well ventilated alveoli. This could clarify typical manifestations of type L COVID-19, such as happy hypoxemia, response to awake prone positioning, response to PEEP/CPAP and platypnea orthodeoxia.
Asunto(s)
COVID-19 , Enfermedades Pulmonares Intersticiales , Síndrome de Dificultad Respiratoria , Humanos , Hipoxia , Enfermedades Pulmonares Intersticiales/diagnóstico , Fenotipo , SARS-CoV-2RESUMEN
A young male who was a heavy smoker presented with spontaneous right pneumothorax. A high resolution computed tomography scan showed disseminated nodules up to 1 cm in diameter; the greatest majority of which were sited in the centrilobular zone, though some abutted on the pleural surface. Surgical lung biopsies allowed a diagnosis of epithelioid haemangioendothelioma. The neoplastic tissue infiltrated the wall of bronchioles, partially obliterating them and the visceral pleura. These two histological aspects could be considered as concomitant mechanisms for the appearance of spontaneous pneumothorax. Epithelioid haemangioendothelioma should be added to the list of lung diseases in young heavy smokers that can begin with a spontaneous pneumothorax.