Measurement of the interbronchial angle in acute viral bronchiolitis.

BACKGROUND: Acute viral bronchiolitis (AVB) is the most common lower airway infection in children under 2 years. Attempts to determine disease severity based on clinical and radiological manifestations are a major challenge. Measurements of the anatomy of the trachea and main bronchi are not only limited to pure anthropometry, but are also useful for better care of critically ill patients. The purpose of the study is to verify the association between measurements of the interbronchial angle (ITB) and the severity of respiratory disease. METHODS: A cross-sectional study, which included all patients admitted to the Santo Antônio Children's Hospital, over a period of 1 year, with diagnosis of AVB by respiratory syncytial virus (RSV) was designed. ITB angle was measured and clinical characteristics were analyzed. Quantitative variables were compared and correlation analysis was performed using Pearson's correlation coefficient. A receiving operator characteristic (ROC) curve was performed. P-value <0.05 was statistically significant. RESULTS: A total of 425 patients with AVB due to RSV were included. Most of these patients were male and the median age was 130 days, 91.11% of them required oxygen therapy through a nasal catheter, 3.3% used noninvasive ventilation and 4% used mechanical ventilation. Those who required MV or NIV and intensive care unit support were considered severe. The mean ITB was lower for these patients than for those of lesser severity (p < 0.05). CONCLUSION: The present study demonstrates that there is an association between ITB and AVB severity. The smaller the ITB, the greater the disease severity.

Validating a bovine model for lung ultrasound of bronchiolitis.

PURPOSE: Bronchiolitis is a very common acute lung disease in infants caused commonly by respiratory syncytial virus (RSV). Point-of-care lung ultrasound is increasingly used in clinical care but proof that ultrasound reflects histological disease is lacking. Bovine calves are a good model for RSV bronchiolitis. We answered the following two questions: (1) does point-of-care lung ultrasound reflect lung pathology at the histological level in a bovine calf model of bronchiolitis? and (2) are point-of-care lung ultrasound images in human infants similar to those obtained in calves? METHODS: We experimentally infected 24 five to six-week-old bovine calves with RSV and compared six window lung ultrasound with lung histology10 days after inoculation. The calves were treated with antivirals and antipyretics leading to variable severity of illness. We used canonical discriminant analysis to determine if abnormal lung ultrasound findings reflected different histological findings. We compared the ultrasounds obtained from the calves with ultrasounds obtained from 10 human infants who were diagnosed clinically with bronchiolitis. RESULTS: Canonical discriminant analysis generally demonstrated good class separation based on the maximal severity of ultrasound finding in each acoustic window. Lung ultrasound performed poorly at detecting bronchopneumonia. Bovine ultrasounds looked similar to human infant lung ultrasounds. CONCLUSION: Point-of-care lung ultrasound abnormalities reflect lung pathology at the histological level in a bovine calf model of bronchiolitis. Point-of-care lung ultrasound images in human infants are similar to those obtained in calves.

Febrile infants without respiratory symptoms or sick contacts: are chest radiographs or RSV/influenza testing indicated?

BACKGROUND: Serious bacterial infection rates in febrile infants < 60 days are about 8-11%. Less than 1% of febrile infants with no respiratory symptoms will have pneumonia however, chest radiography (CXR) rates remain between 30 and 60%. Rapid Respiratory Syncytial Virus (RSV) and influenza (flu) testing is common, however, there is not enough data to determine if febrile infants without any respiratory symptoms should be tested. The goal of this study is to determine the rate of positive CXR and RSV/flu results in febrile infants with no respiratory symptoms and no sick contacts. METHODS: Well-appearing febrile infants between 7 and 60 days of age who presented to the pediatric emergency department (PED) from September 1st, 2015 through October 30th, 2017 were enrolled. Demographic data, respiratory symptoms, CXR findings and RSV/flu results were collected. SAS statistical software was used for analysis. RESULTS: 129 infants met enrollment criteria. Of the 129 infants, 58 (45.0%) had no respiratory symptoms and no sick contacts. Of these 58, 36 (62.1%) received a CXR and none of them had any abnormal findings, 48 (82.8%) had RSV/flu testing, no patients tested positive for RSV and only one patient tested positive for flu. Costs of CXR and RSV/flu testing for this cohort was $19,788. CONCLUSION: The absence of positive CXRs in this patient population reinforces the current recommendations that CXR is not indicated. The low incidence of RSV/flu indicate that routine testing may not be necessary in this population especially outside of the flu season. Reduced testing could decrease overall costs to the healthcare system as well as radiation exposure to this population.

Increase in Detection of Respiratory Syncytial Virus Among Older Adults in Arizona : An Association With Changes in Testing Practices.

OBJECTIVES: Respiratory syncytial virus (RSV) is a common cause of respiratory illness, health care visits, and hospitalizations. Arizona, which began conducting laboratory surveillance in 2004, has noted an increase in RSV cases (defined as a laboratory-positive result) among adults aged ≥65, concurrent with increasing reports from polymerase chain reaction (PCR) testing. We assessed whether the shift in the age distribution of reported RSV cases resulted from a change in RSV testing practices. METHODS: We used data on laboratory-confirmed RSV cases reported during 2013-2017 from the statewide surveillance system to assess the frequency of test types (rapid antigen, immunofluorescence assay, PCR, and viral culture) by age groups across RSV seasons, and we used logistic regression to estimate changes in odds of receiving a PCR test. We used statewide emergency department hospital discharge data for the same period to assess testing practices regardless of test result. RESULTS: The overall proportion of PCR tests among RSV cases increased significantly, from 22% in 2013 to 55% in 2017 (P < .001). The percentage of RSV cases among adults aged ≥65 also increased significantly, from 4% in 2013 to 11% in 2017 (P < .001) of RSV cases. Adults aged ≥65 had more than 8 times the odds of positive PCR results than children aged <5, both in crude (odds ratio [OR] = 8.8; 95% CI, 7.6-10.2) and season-adjusted (adjusted OR = 8.1; 95% CI, 7.0-9.5) models. Hospital discharge data corroborated increased RSV PCR usage from 2013 to 2017. CONCLUSION: Increasing RSV rates among adults aged ≥65 are likely a result of changes in testing practices. This age group may need more targeted intervention and future vaccination.

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

Studies reporting chest images of respiratory syncytial virus (RSV)-induced lower respiratory tract infection (LRTI) in an outbreak setting and their relationship to the clinical manifestation are limited. During a genetically confirmed RSV outbreak, eight patients underwent both chest X-ray and computed tomography (CT). Among these, 5 cases had newly appearing abnormalities on CT, although chest X-ray was able to detect abnormalities in only 2 cases (40%). Although bronchial wall thickening was common, other findings and their distribution were variable, even in an outbreak setting. All patients with both a history of anticancer chemotherapy against hematological cancer and lower respiratory symptoms, such as wheezing, sputum, and hypoxemia, had abnormalities on CT, suggesting that these two factors might be important for predicting the existence of LRTI in RSV-infected patients.

Retrospective Review of Clinical and Chest X-Ray Findings in Children Admitted to a Community Hospital for Respiratory Syncytial Virus Infection.

INTRODUCTION: We performed a retrospective study to evaluate demographics, clinical course, outcome, and radiological findings of children with respiratory syncytial virus (RSV) infection. METHODS: Four hundred patients admitted between October 2013 and May 2016 were enrolled. Clinical and radiographic trends were evaluated for association with severity of RSV presentation. Severity was defined as hospitalization >2 days, pediatric intensive care unit admission, or need for mechanical ventilation. RESULTS: Common clinical findings included fever (78.5%), coughing (97%), rhinorrhea/congestion (93%), and hypoxia (44.8%). Hypoxia was seen in 64.7% of the severe group compared with 32.0% in the nonsevere group ( P < .001). Airspace opacification was seen in 49.2% of chest X-rays of the severe group compared with 26.4% in the nonsevere group ( P < .001). CONCLUSION: Higher incidence of hypoxia or airspace opacification on chest X-ray may be predictors of poorer outcomes for patients with RSV infection.

Complete heart block complicating the acute phase of respiratory syncytial virus bronchiolitis.

Respiratory syncytial virus is the most common pathogen causing lower respiratory tract infection in infants. In recent years, the importance of extrapulmonary complications and longterm sequelae including those involving the cardiovascular system has become apparent. We report on a 10 month old infant with respiratory syncytial virus bronchiolitis, the acute phase of which was complicated by irreversible complete heart block, which was managed conservatively.

Is the role of rhinoviruses as causative agents of pediatric community-acquired pneumonia over-estimated?

The role that rhinoviruses, enteroviruses, parainfluenza viruses, coronaviruses and human bocavirus play in pediatric pneumonia is insufficiently studied. We used polymerase chain reaction (PCR) to study 9 virus groups, including 16 different viruses or viral strains, in 56 ambulatory children with radiologically confirmed community-acquired pneumonia (CAP). The same tests were carried out on 474 apparently healthy control children of the same age and sex. The mean age of children with CAP was 6.5 years (SD 4.2). Respiratory syncytial virus (RSV) was found in 19.6 % of 56 cases and in 2.1 % of 474 controls. Adenoviruses were present in 12.5 % of cases (0.2 % controls) and metapneumovirus and influenza A virus each in 10.7 % of cases (0.2 % controls). Interestingly, rhinoviruses were less common in cases (10.7 %) than in controls (22.4 %): odds ratio 0.36 (95%CI) 0.15-0.87) in conditional logistic regression including 56 cases and 280 controls matched for age, sex and sampling month. The prevalence of parainfluenza viruses, enteroviruses, coronaviruses and human bocavirus were similar in both groups. CONCLUSION: We conclude that the role of rhinoviruses as an etiology of pediatric CAP has been over-estimated, mainly due to the non-controlled designs of previous studies. What is Known: • In non-controlled studies, rhinovirus detection has been common, next to respiratory syncytial virus, in children with viral community-acquired pneumonia (CAP). • Enteroviruses, coronaviruses and the human bocavirus have been found less frequently. What is New: • In this controlled study, rhinoviruses were detected more often in healthy controls than in children with CAP, and enteroviruses, coronaviruses and human bocavirus were detected equally often in cases and controls. • We conclude that previous studies have over-estimated the role of rhinoviruses in the etiology of CAP in children.

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

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.

Is radiological appearance of lower respiratory tract infection due to respiratory syncytial virus a predictor of clinical outcome?

OBJECTIVE: Respiratory syncytial virus (RSV) lower respiratory tract infection is the most common viral infection in childhood. RSV-infected infants demonstrate various radiographic findings. The aim of the study is to evaluate whether assessment of radiological characteristics of lower tract infection due to RSV may be a predictor of clinical outcome in newborns. METHODS: The study included 36 newborn infants hospitalized for lower tract infection. In order to detect RSV, RSV Respi-Strip (Coris Bioconcept Organization) test kits were used on admission. Chest X-rays and clinical characteristics of the study group were reviewed. RESULTS: Of 36 patients hospitalized for lower tract infection from October 2012 to April 2013, 18 (50%) newborns were infected with RSV. The study included 36 neonates. Patients with RSV-positive infants at admission had greater need for respiratory support, supplemental oxygen and prolonged stay in the NICU. Newborns with an atelectasis pattern on admission chest radiograph had greater at RSV-positive infants. CONCLUSION: Chest radiological patterns with lower respiratory tract infection in newborn infants due to RSV are a predictor of clinical outcome.

Initial radiographic features as outcome predictor of adult respiratory syncytial virus respiratory tract infection.

OBJECTIVE: The purposes of this study were to evaluate the chest radiographic features of adult patients hospitalized for respiratory syncytial virus respiratory tract infections and to assess whether initial chest radiographic findings help predict clinical outcome. MATERIALS AND METHODS: All adult patients hospitalized from January 2009 to December 2011 with laboratory-confirmed respiratory syncytial virus infection were included in the study. Patient clinical data and admission chest radiographs were retrospectively reviewed. Adverse outcomes included need for supplemental oxygen, need for assisted ventilation, and death. RESULTS: Of 285 patients (mean age, 74 ± 16 years) included, 199 (69.8%) had abnormal chest radiographic findings: 49.5% (141/285) had acute changes, and 47.7% (136/285) had chronic changes. Consolidation (68/141 [48.2%]) and ground-glass opacity (57/141 [40.4%]) were the predominant types of acute changes and were most common in unilateral single-lower-zone involvement. Consolidation, ground-glass opacity, and chronic changes occurred with significantly higher frequency in patients with adverse outcomes. The presence of acute (odds ratio, 3.6) and chronic (odds ratio, 2.2) changes were independent risk factors for mortality. CONCLUSIONS: A large proportion of adult patients hospitalized with respiratory syncytial virus respiratory tract infection had changes on initial chest radiographs. Consolidation or ground-glass opacity in a unilateral single-lower-zone distribution were the most common findings. The presence of acute and chronic radiographic lung changes was associated with adverse outcomes.

Oral ribavirin therapy for respiratory syncytial virus infections in moderately to severely immunocompromised patients.

BACKGROUND: Respiratory syncytial virus (RSV) infections may be fatal in immunocompromised patients. Aerosolized ribavirin is used for treatment, but it is very costly, teratogenic, and inconvenient. We aimed to assess the outcome of oral ribavirin treatment, with or without intravenous immunoglobulin (IVIG), for RSV infections in moderately to severely immunocompromised patients. METHODS: Medical records of RSV polymerase chain reaction (PCR)-positive patients during 2011-2013 were reviewed retrospectively. Eligible patients were moderately to severely immunocompromised and received oral ribavirin (600-800 mg twice daily) with or without IVIG (500 mg/kg q 48 h) as per protocol. RESULTS: Of 96 adults with PCR-proven RSV infection, 34 were moderately to severely immunocompromised and received oral ribavirin treatment. The mean age was 56.2 years (range: 18-90); 21 were male. Underlying conditions were hematologic malignancy with or without hematopoietic stem cell transplant (n = 25), lung transplant (n = 3), or receipt of cytotoxic chemotherapy (n = 11). The presenting symptoms were cough (94%), fever (62%), and dyspnea (59%). The most common radiographic findings were patchy and nodular infiltrates and opacities. Of 34 patients, 31 were hospitalized, with 13 admitted to the intensive care unit and 6 required mechanical ventilation. The median absolute lymphocyte count on presentation was 480 cells/mm(3) . RSV pneumonia developed in 24 patients. The median initial duration of oral ribavirin treatment was 10 days (range: 4-11); 4 patients were re-treated. Of 34 patients, 19 received a mean of 2.7 doses of IVIG. Two patients had adverse reactions to ribavirin (hemolytic anemia and lactic acidosis in 1 patient, and altered mental status in another). No patient died from RSV infection. Three patients died from complications of their underlying illness; all others recovered clinically. CONCLUSIONS: Oral ribavirin with or without IVIG is a well-tolerated treatment for RSV infection in moderately to severely immunocompromised hosts. Comparative prospective studies should ideally be performed to determine if oral ribavirin is the optimal therapy for RSV infection in this patient population.

CT-morphological characterization of respiratory syncytial virus (RSV) pneumonia in immune-compromised adults.

PURPOSE: Characterization and follow-up evaluation of chest CT of RSV pneumonia in immune-compromised adults during a seasonal epidemic. MATERIALS AND METHODS: Retrospective analysis of 132 chest CT examinations of 51 adult immune-compromised patients (29 m/22f, Ø58 years) with clinical signs of pneumonia and positive RSV test in winter 2011/2012. Two experienced chest radiologists evaluated the morphology (bronchial wall thickening, tree-in-bud, nodules, halo, ground-glass opacities, consolidations, pleural fluid) of the CT scans by consensus. RESULTS: Pathological findings were in 86 % of the chest CT scans: Areas of ground-glass attenuation in 64 %, consolidations in 56 %, nodules in 55 % (Ø 8 mm in maximal diameter, with halo in 71 %), pleural fluid in 44 % (Ø 2 cm), tree-in-bud in 36 %, bronchial wall thickening in 27 % and more than one morphological finding in 72 %. There were no pathological CT findings in 14 % of patients with clinical symptoms of pneumonia because these patients did not undergo follow-up. Radiological progression was found in 45 % of patients and regression in 33 % in follow-up examinations. In 37 % an additional examination of the paranasal sinuses was performed and showed sinusitis in 63 % of cases. 90 % of the patients had sinusitis as well as pneumonia. In addition to RSV, a further pathogenic agent was found in bronchoalveolar lavage of five patients (Aspergillus spec., herpes simplex virus, Pseudomonas aeruginosa). CONCLUSION: The most characteristic signs in chest CT scans were at the beginning of pneumonia with nodules and tree-in-bud often combined with bronchial wall thickening. The following CT scans showed characteristic but not pathognomonic chest CT findings of RSV pneumonia. These morphological findings should be recognized seasonally (winter) especially at the beginning of the case of pneumonia. RSV-associated additional sinusitis is probably common and should be noticed.

Human metapneumovirus (HMPV) associated pulmonary infections in immunocompromised adults--initial CT findings, disease course and comparison to respiratory-syncytial-virus (RSV) induced pulmonary infections.

AIM: To describe computed tomography (CT)-imaging findings in human metapneumovirus (HMPV)-related pulmonary infection as well as their temporal course and to analyze resemblances/differences to pulmonary infection induced by the closely related respiratory-syncytial-virus (RSV) in immunocompromised patients. MATERIALS AND METHODS: Chest-CT-scans of 10 HMPV PCR-positive patients experiencing pulmonary symptoms were evaluated retrospectively with respect to imaging findings and their distribution and results were then compared with data acquired in 13 patients with RSV pulmonary infection. Subsequently, we analyzed the course of chest-findings in HMPV patients. RESULTS: In HMPV, 8/10 patients showed asymmetric pulmonary findings, whereas 13/13 patients with RSV-pneumonia presented more symmetrical bilateral pulmonary infiltrates. Image analysis yielded in HMPV patients following results: ground-glass-opacity (GGO) (n=6), parenchymal airspace consolidations (n=5), ill-defined nodular-like centrilobular opacities (n=9), bronchial wall thickening (n=8). In comparison, results in RSV patients were: GGO (n=10), parenchymal airspace consolidations (n=9), ill-defined nodular-like centrilobular opacities (n=10), bronchial wall thickening (n=4). In the course of the disease, signs of acute HMPV interstitial pneumonia regressed transforming temporarily in part into findings compatible with bronchitis/bronchiolitis. CONCLUSIONS: Early chest-CT findings in patients with HMPV-related pulmonary symptoms are compatible with asymmetric acute interstitial pneumonia accompanied by signs of bronchitis; the former transforming with time into bronchitis and bronchiolitis before they resolve. On the contrary, RSV-induced pulmonary infection exhibits mainly symmetric acute interstitial pneumonia.

Radiological findings in 210 paediatric patients with viral pneumonia: a retrospective case study.

OBJECTIVE: The objective of this study was to assess the radiological presentations of different types of viral pneumonia in children. METHODS: Nasopharyngeal swab specimens and bronchial aspirate samples from children with acute respiratory infections were obtained and tested for influenza B, adenovirus, respiratory syncytial virus and parainfluenza (Types 1, 2 and 3) by direct immunofluorescence assay, or for influenza A (Subtype H1N1) by quantitative real-time polymerase chain reaction. The chest radiographs of the 210 confirmed cases of viral pneumonia were analysed retrospectively by two independent radiologists for the identification, characterisation and description of the distribution of imaging abnormalities. The cases were divided into six groups on the basis of confirmed causative viral agent, and radiographic findings were compared, analysed and presented. RESULTS: The abnormal chest radiograph findings consisted of bilateral patchy areas of consolidation (n=133), interstitial lung disease (n=33), diffuse areas of air space consolidation (n=29) and lobar consolidation (n=15). The abnormalities were distributed bilaterally in 195 cases and observed more frequently in the lower zones than in other regions. The radiological findings varied significantly among the six groups (p=0.0050). Pairwise comparison showed significant difference between influenza A (H1N1) and adenovirus (p=0.0031) only. CONCLUSION: The predominant radiological finding in paediatric viral pneumonia was bilateral patchy areas of consolidation. The radiological findings differed significantly only between adenovirus and influenza A pneumonia. The diagnosis of the specific causative organism requires laboratory confirmation.

Clinical and radiological features of respiratory syncytial virus in solid organ transplant recipients: a single-center experience.

BACKGROUND: Respiratory syncytial virus (RSV) infections range from upper respiratory illness to severe lower respiratory disease. There is no universally accepted treatment for RSV in solid organ transplant (SOT) recipients. METHODS: Retrospective review of adult SOT patients with RSV infections, between January 2007 and December 2009, in a single transplant center was performed. RESULTS: During the 3-year period, a total of 24 adults developed RSV infection, including 12 (50%) SOT recipients (5 kidneys, 4 livers, and 3 lungs). Most cases were seen in 2009 during the influenza H1N1 pandemic, likely as a result of increased testing. In 83% of the cases, the diagnosis was based on RSV antigen detection, which was also used to follow subsequent shedding (mean duration: 20.6 days). Most of the cases presented with lower respiratory disease and required hospitalization. All the patients were on at least two classes of immunosuppressive drugs. We observed a lower lymphocyte count in patients with lower respiratory tract infection. Computed tomography was superior to chest x-ray in demonstrating pulmonary disease, with the most common findings being pulmonary nodules and ground-glass opacities. Novel radiographic findings were small cavities and pleural effusions. No co-infections were documented, and no mortality could be attributed to RSV. Inhaled or oral ribavirin was administered in 67% of the cases, with variations in the treatment regimens. CONCLUSION: SOT recipients accounted for half of all adult cases of RSV at our institution. Type and length of treatment varied widely, and we cannot conclude that outcomes differed between treatments with oral or inhaled ribavirin. Current therapeutic management of RSV in SOT is empiric, and can be rather expensive and difficult, without clear evidence of effectiveness.

Right ventricular function in children with severe respiratory syncytial virus (RSV) bronchiolitis.

BACKGROUND: Previous studies have demonstrated the development of myocardial damage and hepatitis in children with severe respiratory syncytial virus (RSV) infection. The aim of this study was to assess right ventricular function in children with severe RSV disease and to investigate an association with disease severity, myocardial damage, and hepatitis. METHODS: This was a prospective observational study performed at a 20-bed regional multidisciplinary tertiary pediatric intensive care unit (PICU) in a university-affiliated children's hospital. Pulse wave Doppler echocardiographic assessments with a calculation of the right ventricular function (Tei index), left ventricular ejection fraction and diameters, cardiac troponin T levels, transaminase and C-reactive protein levels were performed at admission on consecutive children who were ventilated and diagnosed with a severe RSV infection and without congenital heart disease. RESULTS: Thirty-four ventilated children with confirmed RSV bronchiolitis were enrolled. The median age was 1.4 months (range 0.4-11.7), and the median length of ventilation was 5 days (range 2-10). Seven (20%) infants had an elevated right ventricular Tei index indicating reduced right ventricular function. Left ventricular function as well as C-reactive protein and transaminase levels were not different between patients with and without an elevated right ventricular Tei index. Cardiac troponin T was elevated in 14 patients (41%): 3/7 with an elevated and 11/27 with a normal Tei index (P=1). Ventilation and oxygenation indices and the duration of mechanical ventilation were not different between the two groups. CONCLUSION: A raised right ventricular Tei index, consistent with reduced right ventricular function, was observed in severe RSV disease, but the degree of dysfunction was not related to the level of biochemical myocardial or hepatic damage or level of respiratory support.

Chest CT features of community-acquired respiratory viral infections in adult inpatients with lower respiratory tract infections.

PURPOSE: The appearance of respiratory virus infection on thoracic computed tomography (CT) has been described only to a limited extent in the current literature, and viral pneumonias may be under-recognized by radiologists. Our objective was to describe thoracic CT findings in a broad range of adult inpatients with respiratory virus infections. MATERIALS AND METHODS: A retrospective analysis of chest CTs was performed on symptomatic adult inpatients presenting with positive nucleic acid-based assays for 1 of 4 common community-acquired respiratory viruses. Forty-two patients with viral respiratory tract infections who underwent chest CT imaging were evaluated. The reviewer was blinded to virus type and patient information. CT findings were compared with CT reports produced at the time of the original study and correlated with clinical outcome measures. RESULTS: Influenza (n=21), adenovirus (n=9), respiratory syncytial virus (n=8), and parainfluenza (n=4) were represented among the cohort. Three patterns of the disease were seen with viral infection: (1) limited infection with normal imaging (21%), (2) bronchitis/bronchiolitis characterized by bronchial wall thickening and tree-in bud opacities (31%), and (3) pneumonia characterized by multifocal consolidation or ground-glass opacities (36%). Viral infection was suggested in only 4/42 (10%) of the original radiology reports, all of which had evidence of bronchitis/bronchiolitis on chest CT. Viral pneumonia, characterized by multifocal ground-glass opacities or multifocal consolidations, was interpreted as aspiration pneumonia or bacterial pneumonia in 15/16 (94%) of the original CT reports. CONCLUSIONS: CT scans of the inpatients with community-acquired viral infections most commonly show 1 of 2 patterns: consolidation and ground-glass opacities or bronchial wall thickening and tree-in-bud opacities. It is important that physicians interpreting CTs with multifocal consolidations and/or multifocal ground-glass opacities consider viral pneumonia when these findings are observed and recommend appropriate diagnostic testing when clinically warranted.

Chest radiological patterns predict the duration of mechanical ventilation in children with RSV infection.

BACKGROUND: RSV-infected children demonstrate various radiographic features, some of which are associated with worse clinical outcomes. OBJECTIVE: To investigate whether specific chest radiological patterns in RSV-infected children with acute respiratory failure (ARF) in the peri-intubation period are associated with prolonged duration of mechanical ventilation. MATERIALS AND METHODS: We included RSV-infected children <1 year of age admitted with ARF from 1996 through 2002 to the pediatric intensive care unit at Massachusetts General Hospital. Their chest radiographs were evaluated at three time-points: preintubation (day -1) and days 1 and 2 after intubation. Univariate and multiple logistic regressions models were utilized to investigate our objective. RESULTS: The study included 46 children. Using day 1 chest radiograph findings to predict duration of mechanical ventilation of >8 days, a backward stepwise regression arrived at a model that included age and right and left lung atelectasis. Using day 2 chest radiograph results, the best model included age and left lung atelectasis. A model combining the two days' findings yielded an area under the ROC curve of 0.92 with a satisfactory fit (P = 0.95). CONCLUSION: Chest radiological patterns around the time of intubation can identify children with RSV-associated ARF who would require prolonged mechanical ventilation.