CT findings in viral lower respiratory tract infections caused by parainfluenza virus, influenza virus and respiratory syncytial virus

Abstract

Viral lower respiratory tract infections (LRTIs) can present with a variety of computed tomography (CT) findings. However, identifying the contribution of a particular virus to CT findings is challenging due to concomitant infections and the limited data on the CT findings in viral LRTIs. We therefore investigate the CT findings in different pure viral LRTIs.All patients who underwent bronchoalveolar lavage (BAL) and were diagnosed with LRTIs caused by parainfluenza virus (PIV), influenza virus, or respiratory syncytial virus (RSV) between 1998 and 2014 were enrolled in a tertiary hospital in Seoul, South Korea. A pure viral LRTI was defined as a positive viral culture from BAL without any positive evidence from respiratory or blood cultures, or from polymerase chain reaction (PCR), or from serologic tests for bacteria, fungi, mycobacteria, or other viruses.CT images of 40 patients with viral LRTIs were analyzed: 14 with PIV, 14 with influenza virus, and 12 with RSV. Patch consolidation (≥1 cm or more than 1 segmental level) was found only in PIV (29%) (P = 0.03), by which CT findings caused by PIV could resemble those seen in bacterial LRTIs. Ground-glass opacities were seen in all cases of influenza virus and were more frequent than in PIV (71%) and RSV (67%) (P = 0.05). Bronchial wall thickening was more common in influenza virus (71%) and RSV (67%) LRTIs than PIV LRTIs (21%) (P = 0.02). With respect to anatomical distribution, PIV infections generally affected the lower lobes (69%), while influenza virus mostly caused diffuse changes throughout the lungs (57%), and RSV frequently formed localized patterns in the upper and mid lobes (44%).The CT findings in LRTIs of PIV, influenza virus, and RSV can be distinguished by certain characteristics. These differences could be useful for early differentiation of these viral LRTIs, and empirical use of appropriate antiviral agents.

COVID-19 pneumonia: CT findings of 122 patients and differentiation from influenza pneumonia

“…Both COVID-19 and influenza groups involved bilateral lungs with multiple lung lobes, and a majority of patients in both groups involved all five lobes, which was consistent with previous studies [9,[13][14][15][16]. However, the COVID-19 group mainly involved peripheral part of the lung, which was in line with other coronavirus infection such as SARS [17], while influenza pneumonia was more diffuse and involved both central and peripheral parts.…”

“…Interlobular septal thickening is a common sign on thin-slice chest CT; it may be seen in the presence of interstitial fluid, cellular infiltration, or fibrosis. This sign can be found in various viral pneumonias such as parainfluenza, Hantavirus, and SARS [9,22]. Edema and smooth muscle hyperplasia could result in bronchiolar wall thickening, which has been reported in influenza, parainfluenza, and adenovirus [17,22].…”

“…Recently, Bai et al compared the chest CT features of COVID-19 pneumonia and non-COVID-19 viral pneumonia, and found that COVID-19 pneumonia was more likely to have a peripheral distribution and ground-glass opacity [8]. However, there are several kinds of respiratory tract viruses that may lead to viral pneumonia, and the CT features of the different kinds of viral pneumonia may be different [9]. Influenza pneumonia is among the most common viral pneumonia, and now it is just during the "flu season"; therefore, it is essential to differentiate COVID-19 pneumonia from influenza.…”

Chest Computed Tomography Abnormalities and Their Relationship to the Clinical Manifestation of Respiratory Syncytial Virus Infection in a Genetically Confirmed Outbreak

“…Respiratory syncytial virus (RSV) is well known as a virus causing lower respiratory tract infection (LRTI) in infants and immunocompromised adults (1)(2)(3). Bronchopneumonia patterns are common findings of RSV-induced LRTI (RSV-LRTI); however, RSV-LRTI often shows variable findings on chest imaging (4)(5)(6)(7)(8)(9)(10)(11). Although some factors, such as the virulence of RSV and host immune status, might affect the chest computed tomography (CT) findings of RSV-LRTI (12,13), the detailed mechanisms remain unknown.…”

Is Follow-Up Endoscopy Necessary in Upper Gastrointestinal Cytomegalovirus Disease?

“…In the articles “Is Follow-Up Endoscopy Necessary in Upper Gastrointestinal Cytomegalovirus Disease?”, [ 1 ] which appeared in Volume 95, Issue 19 of Medicine , and “CT Findings in Viral Lower Respiratory Tract Infections Caused by Parainfluenza Virus, Influenza Virus and Respiratory Syncytial Virus”, [ 2 ] which appeared in Volume 95, Issue 26 of Medicine , the Asan Institute of Life Sciences grant number was originally reported incorrectly. The correct grant number in both articles is 2016-462.…”