Diagnosis of coronavirus disease 2019 pneumonia in pregnant women: can we rely on lung ultrasound?

Abstract

In the case report by Inchingolo et al,1Inchingolo R. Smargiassi A. Moro F. et al.The diagnosis of pneumonia in a pregnant woman with COVID-19 using maternal lung ultrasound.Am J Obstet Gynecol. 2020; ([Epub ahead of print])Google Scholar the authors recommend lung ultrasound (US) examination as a diagnostic imaging tool for pregnant women with suspected coronavirus disease 2019 (COVID-19). The typical US findings of COVID-19 pneumonia, described by authors, are as follows: (1) a patchy distribution of interstitial artifactual signs (single or confluent vertical artifacts, small white lung regions), (2) an extended distribution of the previously mentioned interstitial artifactual signs to multiple areas of the lung surface, and (3) small subpleural consolidation (not described in this case report1Inchingolo R. Smargiassi A. Moro F. et al.The diagnosis of pneumonia in a pregnant woman with COVID-19 using maternal lung ultrasound.Am J Obstet Gynecol. 2020; ([Epub ahead of print])Google Scholar). In this regard, we feel the need to clarify some points and raise some doubts. The evaluation of the extent of pulmonary involvement is limited by incomplete accessibility of the lung with US: less than 70% of the pleural surface of lung is visible. The vertical artifacts (B-lines) are an “error of image” generated when sound waves interact with gas microbubbles, which in turn causes the fluid film trapped between them to resonate. These artifacts have been described in fluid-filled dilated bowel loops, in the normal lung, and even in the residual cavity of a postpneumonectomy and are totally absent in intraoperative lung US scan of patients with interstitial lung diseases on account of their nature of imaging errors being related to the difference in acoustic impedance of superficial or deeper structures.2Quarato C.M.I. Venuti M. Sperandeo M. The artificial count of artifacts for thoracic ultrasound: what is the clinical usefulness?.J Clin Monit Comput. 2020; ([Epub ahead of print])Crossref PubMed Scopus (9) Google Scholar An increased number of B-lines, single or confluent, indicate the presence of an underlying unspecific pleuropulmonary disease. Indeed, this sonographic pattern is not pathognomonic of COVID-19, but it is shared by most other lung diseases (acute respiratory distress syndrome, heart failure, nephrotic syndrome, pneumonia, minimal pleural effusion, hydropneumothorax, fibrosis, emphysema, exacerbations of chronic obstructive pulmonary disease, and lymphangitis).2Quarato C.M.I. Venuti M. Sperandeo M. The artificial count of artifacts for thoracic ultrasound: what is the clinical usefulness?.J Clin Monit Comput. 2020; ([Epub ahead of print])Crossref PubMed Scopus (9) Google Scholar,3Sperandeo M. Rea G. Interstitial lung diseases.in: Feletti F. Malta B. Aliverti A. Thoracic ultrasound and integrated imaging. Springer International Publishing, Cham, Switzerland2020: 61-82Crossref Google Scholar The authors did not compare the US findings in their documented patient with COVID-19 with the gold standard (computed tomography scan). Therefore, the number and type of lesions present in the patient’s lung are not known. In this case report, focal and sporadic ground-glass opacity (GGO), interlobular and intralobular septal thickening, patchy or extensive peripheral GGO, and peripheral dense pulmonary consolidation not adherent to the pleural surface have not been assessed: this is not the best diagnostic practice for appropriate therapy. With the exception of US-guided procedures and interventions, the use of US in COVID-19 pneumonia is very restricted and sometimes can be confusing because of the nonspecific findings.4Sperandeo M. Trovato G.M. Lung ultrasound early detection and monitoring in Covid-19 pneumonia: fact and fiction.QJM. 2020; ([Epub ahead of print])Crossref PubMed Scopus (5) Google Scholar The use of US in the diagnosis of COVID-19 pneumonia must be firmly discouraged to avoid needless exposure of medical staff and because it may be misleading. The diagnosis of pneumonia in a pregnant woman with coronavirus disease 2019 using maternal lung ultrasoundAmerican Journal of Obstetrics & GynecologyVol. 223Issue 1PreviewLung ultrasound examination has been demonstrated to be an accurate imaging method to detect pulmonary and pleural conditions. During pregnancy, there is a need for rapid assessment of the maternal lung in patients with suspected coronavirus disease 2019. We report our experience on lung ultrasound examination in the diagnosis of coronavirus disease 2019 pneumonia in a pregnant woman. Typical ultrasound features of this pulmonary pathology, including diffuse hyperechoic vertical artifacts with thickened pleural line and “white lung” with patchy distribution, were observed. Full-Text PDF ReplyAmerican Journal of Obstetrics & GynecologyVol. 223Issue 4PreviewIn April 2020, we reported our experience performing lung ultrasound (LUS) on the first pregnant woman admitted for coronavirus disease 2019 (COVID-19) pneumonia.1 Full-Text PDF