Distribution Of Parenchymal Abnormalities Research Articles

Extent and Distribution of Parenchymal Abnormalities in Baseline CT-Scans Do Not Predict Awake Prone Positioning Response in COVID-19 Related ARDS.

Prone positioning is frequently used for non-intubated hypoxemic patients with COVID-19, although conclusive evidence is still lacking. The aim of the present study was to investigate whether baseline CT-scans could predict the improvement in oxygenation in COVID-19 related Acute respira-tory syndrome (ARDS) patients when pronated. Methods: A retrospective study of COVID-19 patients who underwent non-invasive ventilation (NIV) and prone positioning was conducted. Results: Forty-five patients were included. On average, 50% of the overall lung volume was affected by the disease, as observed in the CT-scans, with ground glass opacities (GGOs) and consolidations accounting for 44% and 4%, respectively. The abnormalities were mainly posterior, as demonstrated by posterior/anterior distribution ratios of 1.5 and 4.4 for GGO and consolidation, respectively. The median PaO2/FiO2 ratio during NIV in a supine position (SP1) was 140 [IQR 108–169], which improved by 67% (+98) during prone positioning, on average. Once supine positioning was resumed (SP2), the improvement in oxygenation was maintained in 28 patients (62% of the overall population, categorized as “responders”). We found no significant differences between responders and non-responders in terms of the extent (p = 0.92) and the distribution of parenchymal abnormalities seen in the baseline CT (p = 0.526). Conclusion: Despite the lack of a priori estimation of the sample size, considering the absence of any trends in the differences and correlations, we can reasonably conclude that the baseline chest CT-scan does not predict a gas-exchange response in awake prone-positioned patients with COVID-19 related ARDS. Physicians dealing with this category of patients should not rely on the imaging at presentation when evaluating whether to pronate patients.

Diagnostic accuracy and prognostic value of lung ultrasound in coronavirus disease (COVID-19).

PurposeThis study aimed to assess the correlation between lung ultrasound (LUS) and computed tomography (CT) findings and the predictability of LUS scores to anticipate disease characteristics, lab data, clinical severity, and mortality in patients with COVID-19.Material and methodsFifty consecutive hospitalized PCR-confirmed COVID-19 patients who underwent chest CT scan and LUS on the first day of admission were enrolled. The LUS score was calculated based on the presence, severity, and distribution of parenchymal abnormalities in 14 regions.ResultsThe participants’ mean age was 54.60 ± 19.93 years, and 26 (52%) were female. All patients had CT and LUS findings typical of COVID-19. The mean value of CT and LUS severity scores were 11.80 ± 3.89 (ranging from 2 to 20) and 13.74 ± 6.43 (ranging from 1 to 29), respectively. The LUS score was significantly higher in females (p = 0.016), and patients with dyspnoea (p = 0.048), HTN (p = 0.034), immunodeficiency (p = 0.034), room air SpO2 ≤ 93 (p = 0.02), and pleural effusion (p = 0.036). LUS findings were strongly correlated with CT scan results regarding lesion type, distribution, and severity in a region-by-region fashion (92-100% agreement). An LUS score of 14 or higher was predictive of room air SpO2 ≤ 93 and ICU admission, while an LUS score ≥ 12 was predictive of death (p = 0.011, 0.023, and 0.003, respectively).ConclusionsOur results suggested that LUS can be used as a valuable tool for detecting COVID-19 pneumonia and determining high-risk hospitalized patients, helping to triage and stratify high-risk patients, which waives the need to undertake irradiating chest CT and reduces the burden of overworked CT department staff.

Prognostic Implications of CT Feature Analysis in Patients with COVID-19: a Nationwide Cohort Study.

BackgroundFew studies have classified chest computed tomography (CT) findings of coronavirus disease 2019 (COVID-19) and analyzed their correlations with prognosis. The present study aimed to evaluate retrospectively the clinical and chest CT findings of COVID-19 and to analyze CT findings and determine their relationships with clinical severity.MethodsChest CT and clinical features of 271 COVID-19 patients were assessed. The presence of CT findings and distribution of parenchymal abnormalities were evaluated, and CT patterns were classified as bronchopneumonia, organizing pneumonia (OP), or diffuse alveolar damage (DAD). Total extents were assessed using a visual scoring system and artificial intelligence software. Patients were allocated to two groups based on clinical outcomes, that is, to a severe group (requiring O2 therapy or mechanical ventilation, n = 55) or a mild group (not requiring O2 therapy or mechanical ventilation, n = 216). Clinical and CT features of these two groups were compared and univariate and multivariate logistic regression analyses were performed to identify independent prognostic factors.ResultsAge, lymphocyte count, levels of C-reactive protein, and procalcitonin were significantly different in the two groups. Forty-five of the 271 patients had normal chest CT findings. The most common CT findings among the remaining 226 patients were ground-glass opacity (98%), followed by consolidation (53%). CT findings were classified as OP (93%), DAD (4%), or bronchopneumonia (3%) and all nine patients with DAD pattern were included in the severe group. Uivariate and multivariate analyses showed an elevated procalcitonin (odds ratio [OR], 2.521; 95% confidence interval [CI], 1.001–6.303, P = 0.048), and higher visual CT scores (OR, 1.137; 95% CI, 1.042–1.236; P = 0.003) or higher total extent by AI measurement (OR, 1.048; 95% CI, 1.020–1.076; P < 0.001) were significantly associated with a severe clinical course.ConclusionCT findings of COVID-19 pneumonia can be classified into OP, DAD, or bronchopneumonia patterns and all patients with DAD pattern were included in severe group. Elevated inflammatory markers and higher CT scores were found to be significant predictors of poor prognosis in patients with COVID-19 pneumonia.

Effect of combination antiretroviral therapy on the clinical manifestations, radiological characteristics, and disease severity of HIV-associated Talaromyces marneffei infection.

The objective of this study was to evaluate whether combination antiretroviral therapy (cART) has an effect on the clinical manifestations, radiological characteristics, and disease severity of human immunodeficiency virus (HIV)-associated Talaromyces marneffei infection. The clinical manifestations, chest computed tomography (CT) images, and disease severity were compared between 14 patients with culture-confirmed T. marneffei infections who received cART and 38 patients who did not receive cART. Clinical manifestations included high fever (>38°C), cough, shortness of breath, chills, and skin rash. Chest CT scans were evaluated for the presence of ground-glass opacities, consolidation, miliary nodules, nodules, masses, cavitation, pericardial effusion, pleural effusion, mediastinal lymphadenitis, and the distribution of parenchymal abnormalities. Disease severity was estimated by clinical manifestations and chest CT findings. Fever (>38°C), cough, shortness of breath, and chills were significantly less frequent in patients who received cART than in those who did not receive cART (P < 0.05). The frequencies of miliary nodules, mediastinal lymphadenitis, and the proportion of diffuse lesions were significantly lower in patients who received cART than in those who did not receive cART (P < 0.05). The disease severity was significantly decreased in patients who received cART compared with patients who did not receive cART (P < 0.001). T. marneffei-infected patients who received cART had fewer clinical manifestations and decreased disease severity compared with those who did not receive this treatment. The use of cART is associated with modified chest CT characteristics in HIV-associated T. marneffei infections.

Computed Tomography Findings of Influenza A (H1N1) Pneumonia in Adults

The aim of this study was to evaluate retrospectively the chest computed tomography findings of influenza A (H1N1) pneumonia and their relationship with clinical outcome. Chest computed tomography findings and clinical outcomes of 76 patients with influenza A (H1N1) pneumonia were assessed. Computed tomography findings were evaluated for the presence and distribution of parenchymal abnormalities, which were then classified into 3 patterns: bronchopneumonia, cryptogenic organizing pneumonia (COP), and acute interstitial pneumonia (AIP) patterns. Clinical courses were divided into 2 groups on the basis of necessitating admission to intensive care unit or mechanical ventilation therapy (group 1) or not (group 2). Lung abnormalities consisted of ground-glass opacity (93%, 71 patients), consolidation (66%, 50 patients), small nodules (61%, 46 patients), and tree-in-bud sign (22%, 17 patients). Lesions were classified into bronchopneumonia (49%, 37 patients), COP (30%, 23 patients), AIP (18%, 14 patients), and unclassifiable (3%, 2 patients) patterns. Patients with AIP pattern had a tendency to belonging to group 1, accounting for 40% (8 of 20 patients) of group 1 course and only 11% (6 of 56 patients) of group 2 course (P = 0.004). Computed tomography findings of influenza A (H1N1) pneumonia in adults can be classified into COP, AIP, and bronchopneumonia patterns. Patients presenting with AIP pattern have a tendency to show poor prognosis.

Pulmonary Complications of Illicit Drug Use

The aim of this manuscript is to summarize an approach to the differential diagnosis of the pulmonary complications of illicit drug use based on the computed tomography findings. The various pulmonary complications of illicit drug use result in 5 main patterns of parenchymal abnormality: nodules, ground-glass opacities, consolidation, air trapping, and emphysema. Other thoracic manifestations of illicit drug use include pulmonary arterial hypertension, pneumomediastinum, bacterial endocarditis, discitis, and septic arthritis.

Drug-associated Organizing Pneumonia: High-resolution CT Findings in 9 Patients

To assess the high-resolution computed tomography appearances of drug-associated organizing pneumonia (OP). Nine patients with clinical and biopsy proven drug-associated OP were included in the study. High-resolution computed tomography exams were retrospectively reviewed by 2 observers for the presence, extent, and distribution of parenchymal abnormalities. The commonest findings consisted of air space consolidation (n = 8) and ground-glass opacification (n = 7). The air space consolidation was bilateral and asymmetric in 7 patients, symmetric in 1 patient and in all cases involved mainly the peribronchial or subpleural regions or both. The ground-glass opacities were predominantly bilateral and asymmetric in 6 patients and unilateral in 1 patient. They had a patchy distribution in 4 patients, were diffuse in 2 patients, and subpleural in 1 patient. Drug-associated OP most commonly presents with bilateral, asymmetrical air space consolidation in a predominantly peribronchial and subpleural distribution.

Pulmonary Cryptococcosis: Comparison of Clinical and Radiographic Characteristics in Immunocompetent and Immunocompromised Patients

We compared the clinical characteristics and imaging findings between immunocompetent and immunocompromised patients in whom pulmonary cryptococcosis had been diagnosed to define the role of serum cryptococcal antigen (sCRAG) and radiographs during a follow-up period of up to 1 year. Retrospective cohort study. University hospital. The clinical records, chest radiographs, and CT scan findings of 13 immunocompetent and 16 immunocompromised patients with a diagnosis based on cerebrospinal fluid (CSF) culture, sCRAG titers, and cytologic or histologic confirmation of the presence of pulmonary cryptococcosis were reviewed during the course of the study. Two thoracic radiologists reviewed chest radiographs and CT scans for morphologic characteristics and the distribution of parenchymal abnormalities, and a final reading was reached by consensus. The correlation between serial radiographs and sCRAG titers was examined in 9 immunocompetent and 10 immunocompromised patients. Serum or CSF cryptococcal antigen. The most common clinical symptom was cough, which was present in 24 patients (82.8%). Pulmonary nodules were the most frequent radiologic abnormality. Cavitation within nodules and parenchymal consolidation were significantly less common in immunocompetent patients compared to immunocompromised patients (p = 0.02 and p = 0.05, respectively). Immunocompromised patients tended to have a larger extent of pulmonary involvement than immunocompetent patients, the changes seen on their serial radiographs were more variable, and their corresponding sCRAG titers were higher (> 1:256). In the immunocompetent patients, the radiographic characteristics of lesions usually improved with a corresponding decrease in sCRAG titers over time. Our study suggests that pulmonary cryptococcosis usually follows a benign clinical course in immunocompetent patients. Immunocompromised patients often undergo an evolution to cavitary lesions that represent a more aggressive disease nature. Serial radiographic changes and changes in sCRAG titers reliably reflect disease progression and the response to therapy.

Bronchiolitis Obliterans Organizing Pneumonia After Bone Marrow Transplantation

To assess the high-resolution computed tomography (HRCT) appearances of bronchiolitis obliterans organizing pneumonia (BOOP) after bone marrow transplantation (BMT). The HRCT scans obtained in 4 patients (2 men and 2 women, age range: 20-50 years, mean age = 36 years) with biopsy-proven BOOP after BMT were reviewed retrospectively by 2 observers for the presence, extent, and distribution of parenchymal abnormalities. All patients demonstrated consolidation and ground-glass opacity. The consolidation was bilateral, patchy, and asymmetric in all patients and was predominantly peribronchovascular in 3 patients and subpleural and peribronchovascular in 1 patient. Ground-glass opacity was patchy and asymmetric in all patients and was bilateral in 3 patients and unilateral in 1 patient. No zonal predominance of either feature could be identified. The predominant HRCT features of BOOP after BMT are bilateral, patchy, and asymmetric consolidation in a predominantly peribronchovascular distribution with associated ground-glass opacity.

Pulmonary Candidiasis after Hematopoietic Stem Cell Transplantation: Thin-Section CT Findings

To retrospectively evaluate thin-section computed tomographic (CT) findings in hematopoietic stem cell transplant (ie, bone marrow transplant) patients with histopathologically proved pulmonary candidiasis. Ethical approval was obtained from the institutional review board of each of the three institutions; informed consent was not required. The study included 17 hematopoietic stem cell transplant recipients with proved pulmonary candidiasis. Histopathologic specimens were acquired at transbronchial biopsy (n = 8), open lung biopsy (n = 6), and autopsy (n = 3). The patients included seven men and 10 women (age range, 20-62 years; mean age, 37 years). The thin-section CT scans were retrospectively reviewed by two thoracic radiologists for the presence, appearance, and distribution of parenchymal abnormalities. Multiple nodules were present in 15 (88%) patients, including centrilobular nodules and tree-in-bud pattern in seven (41%) patients. Nodules were bilateral in 12 patients and unilateral in three. An associated halo of ground-glass opacity was identified in five (33%) patients. Nodules were the only CT finding in five patients (29%). Areas of air-space consolidation were identified in 11 (65%) patients. Areas of ground-glass opacity were seen in six (35%) of 17 patients and were always associated with other abnormalities. Other less common CT findings included pleural effusion (n = 3), thickening of the bronchial walls (n = 2), and cavitation (n = 1). The most common thin-section CT findings of pulmonary candidiasis in hematopoietic stem cell transplant patients are multiple bilateral nodular opacities often associated with areas of consolidation.

Exogenous Lipoid Pneumonia: Serial Chest Plain Roentgenography and High-Resolution Computerized Tomography Findings

Between May 1988 and July 2002, six patients with pneumonia due to diesel, animal, or vegetable oil aspiration were admitted to Kaohsiung Medical University Hospital. The purpose of this study was to demonstrate distinctive radiographic findings of oil-induced lipoid pneumonitis on initial serial chest roentgenograms and high-resolution computerized tomography (CT) scans. Initial chest roentgenograms (n = 6), CT scans (n = 6), and roentgenography and CT follow-up studies were analyzed retrospectively by two chest radiologists and two surgeons, focusing on the pattern and distribution of parenchymal abnormalities. The most common location was the right middle lobe, followed by the right lower lobe, the left lower lobe, and the lingular lobe. Follow-up chest roentgenograms (n = 6) showed complete disappearance of the parenchymal lesions in only one patient and partial decrease in the extent of lesions in five patients. Lipoid pneumonia presents non-specific findings on chest roentgenography. It is commonly located in both lower and the right middle lobes. On high-resolution CT, the lesions appear most commonly as areas of consolidation, ground-glass attenuation mixed with paving pattern, and poorly defined nodules.

Pulmonary cryptococcosis: CT and pathologic findings.

The purpose of this work was to describe the CT and pathologic findings of pulmonary cryptococcosis. CT scans of 11 patients (7 immunocompromised, 4 immunocompetent) with proven pulmonary cryptococcosis were analyzed for number, morphologic characteristics, and distribution of parenchymal abnormalities as well for presence of lymphadenopathy and pleural effusion. Pathology of lung specimens obtained by open biopsy or resection (n = 5) and transbronchial biopsy (n = 1) was reviewed by one dedicated pulmonary pathologist. Pulmonary nodules, either solitary or multiple, were the most common CT finding, present in 10 of 11 patients (91%); associated findings included masses (n = 4), CT halo sign (n = 3), and consolidation (n = 2). On histologic examination, focal areas of ground-glass attenuation surrounding or adjacent to nodules were found to represent airspace collections of macrophages and proteinaceous fluid. Pulmonary cryptococcosis should be considered in the differential diagnosis of solitary or multiple pulmonary nodules (with or without associated CT halo sign), particularly in immunocompromised patients.

Squalene-induced extrinsic lipoid pneumonia: serial radiologic findings in nine patients.

The purpose of this work was to demonstrate the initial and follow-up radiologic findings of squalene-induced extrinsic lipoid pneumonia. Follow-up chest radiographs (n = 9) and high-resolution CT scans (n = 3) as well as initial radiographs (n = 9) and CT scans (n = 8) were obtained in nine patients with squalene-induced extrinsic lipoid pneumonia. The serial radiologic findings were analyzed retrospectively by three chest radiologists, focusing on the pattern and distribution of parenchymal abnormalities. The most frequent pattern of parenchymal abnormalities on chest radiograph was areas of ground-glass opacity (n = 9, bilateral 6), followed by consolidation (n = 7, bilateral 3) and poorly defined small nodules (n = 4, bilateral 2). The abnormalities were distributed in the right lower lung (n = 9), left lower lung (n = 6), and right middle lung (n = 6) zones. Initial CT scans (n = 8) demonstrated bilateral areas of ground-glass attenuation (n = 8), poorly defined centrilobular nodules (n = 8), crazy paving (n = 6), and consolidation (n = 3). The abnormalities were distributed in the right middle lobe (n = 8) and in both lower lobes (n = 5). Follow-up chest radiograph (n = 9) showed complete disappearance (n = 2) and decrease (n = 7) in the extent of the parenchymal abnormalities. Follow-up CT scans (n = 3) demonstrated decrease (n = 2) and no change (n = 1) in the extent of the abnormalities. Squalene-induced extrinsic lipoid pneumonia most commonly appears as areas of ground-glass attenuation mixed with poorly defined centrilobular nodules and crazy paving on CT, being distributed mainly in the right middle and both lower lobes. The lesions are indolent and remain after cessation of squalene ingestion.

Chronic hypersensitivity pneumonitis: use of CT in diagnosis.

In its subacute or chronic form, hypersensitivity pneumonitis is often difficult to distinguish clinically and physiologically from other idiopathic diffuse lung diseases. The aim of this study was to identify high-resolution CT features that allow distinction of chronic hypersensitivity pneumonitis from other chronic diffuse parenchymal lung diseases. Six patients with chronic hypersensitivity pneumonitis were examined with pulmonary function testing, bronchoalveolar lavage, lung biopsy, chest radiography, and high-resolution CT. The chest radiographs and high-resolution CT scans were reviewed independently by three observers without knowledge of the patients' clinical status. Discrepancies between the observers were resolved by consensus. The chest radiographs revealed normal lung volumes with a combination of abnormalities: a mixed alveolar/interstitial pattern in five cases, peribronchiolar thickening in three, a diffuse granular pattern in one, and a linear fibrotic pattern in one. In general, the high-resolution CT scans showed more abnormalities than were apparent on the plain chest radiographs. High-resolution CT revealed centrilobular, peribronchiolar, indistinct nodular opacities, of various numbers, in all cases. Four cases had areas of ground-glass density, three cases had lobular areas of hyperlucency, and one case had areas of pulmonary fibrosis and honeycombing. We confirm that high-resolution CT can most clearly show the type and distribution of parenchymal abnormalities in patients with hypersensitivity pneumonitis. Importantly, although not pathognomonic, the high-resolution CT finding of centrilobular, peribronchiolar, indistinct nodules should suggest the diagnosis of chronic hypersensitivity pneumonitis.