Acute kidney injury in hospitalized patients with nonmalignant pleural effusions: a retrospective cohort study.

BACKGROUND: Nonmalignant pleural effusion (NMPE) is common and remains a definite health care problem. Pleural effusion was supposed to be a risk factor for acute kidney injury (AKI). Incidence of AKI in NMPE patients and whether there is correlation between the size of effusions and AKI is unknown. OBJECTIVE: To assess the incidence of AKI in NMPE inpatients and its association with effusion size. STUDY DESIGN AND METHOD: We conducted a retrospective cohort study of inpatients admitted to the Chinese PLA General Hospital with pleural effusion from 2018-2021. All patients with pleural effusions confirmed by chest radiography (CT or X-ray) were included, excluding patients with diagnosis of malignancy, chronic dialysis, end-stage renal disease (ESRD), community-acquired AKI, hospital-acquired AKI before chest radiography, and fewer than two serum creatinine tests during hospitalization. Multivariate logistic regression and LASSO logistic regression models were used to identify risk factors associated with AKI. Subgroup analyses and interaction tests for effusion volume were performed adjusted for the variables selected by LASSO. Causal mediation analysis was used to estimate the mediating effect of heart failure, pneumonia, and eGFR < 60 ml/min/1.73m2 on AKI through effusion volume. RESULTS: NMPE was present in 7.8% of internal medicine inpatients. Of the 3047 patients included, 360 (11.8%) developed AKI during hospitalization. After adjustment by covariates selected by LASSO, moderate and large effusions increased the risk of AKI compared with small effusions (moderate: OR 1.47, 95%CI 1.11-1.94 p = 0.006; large: OR 1.86, 95%CI 1.05-3.20 p = 0.028). No significant modification effect was observed among age, gender, diabetes, bilateral effusions, and eGFR. Volume of effusions mediated 6.8% (p = 0.005), 4.0% (p = 0.046) and 4.6% (p < 0.001) of the effect of heart failure, pneumonia and low eGFR on the development of AKI respectively. CONCLUSION: The incidence of AKI is high among NMPE patients. Moderate and large effusion volume is independently associated with AKI compared to small size. The effusion size acts as a mediator in heart failure, pneumonia, and eGFR.

A new dynamic nomogram for predicting the risk of severe Mycoplasma pneumoniae pneumonia in children.

Mycoplasma pneumoniae pneumonia (MPP) is usually mild and self-limiting, but still about 12% of them will progress to severe Mycoplasma pneumoniae pneumonia (SMPP), which have poor survival rates and often require intensive medical resource utilization. We retrospectively collected clinical data from 526 children with MPP admitted to the Children's Hospital Affiliated to Zhengzhou University from June 2018 to February 2023 and randomly divided the data into a training cohort and a validation cohort at a ratio of 4:1. Univariate and multivariate logistic regressions were used to identify independent risk factors for SMPP. Age, AGR, NLR, CRP, ESR, MPV, coinfection, pleural effusion, primary disease, fever days ≥ 7 and wheeze are independent risk factors for SMPP in children. Then, we built an online dynamic nomogram ( https://ertongyiyuanliexiantu.shinyapps.io/SMPP/ ) based on the 11 independent risk factors. The C-index, ROC curve, DCA curve and calibration curve were used to assess the performance of the nomogram, which all showed that the dynamic nomogram has excellent clinical value. Based on age, AGR, NLR, CRP, ESR, MPV, coinfection, pleural effusion, primary disease, fever days ≥ 7 and wheeze, the first dynamic nomogram for accurately predicting SMPP was successfully established.

An 88-Year-Old Woman With Pneumothorax and Black Pleural Effusion.

CASE PRESENTATION: An 88-year-old woman was admitted to our hospital with the sudden onset of dyspnea after eating. The patient had undergone nephrectomy for a left renal tumor 24 years previously. The patient had been prescribed ferrous citrate for iron-deficiency anemia. She complained of appetite loss a few days before admission but had no abdominal pain. CT scan showed no abnormalities in the lungs but a mass in the liver.

Clinical characteristics and changes in serum CXCL10 and CXCL16 levels in patients with severe mycoplasma pneumonia.

To explore the clinical characteristics and changes in serum CXCL10 and CXCL16 in patients with severe mycoplasma pneumonia, and to analyze the risk factors of severe mycoplasma pneumonia. About 258 children with acute mycoplasma pneumoniae pneumonia (MPP) admitted to the respiratory department of a certain hospital from January 2020 to December 2022 were selected as the study subjects. According to the severity of MPP, patients are divided into 2 groups, namely the mild illness group (Q group) and the severe illness group (Z group). The number of cases in these 2 groups of children is 167 and 91, respectively. The serum CXCL10, CXCL16, and other indicators of 2 groups are tested. Compared to group Q, patients in group Z have a higher proportion of extrapulmonary complications, longer cough time, longer shortness of breath, and longer wheezing time (P < .05). The serum CXCL16 is higher and the proportion of pleural effusion is higher (P < .01). There are more cases of fever, longer fever duration, longer hospital stay, higher serum CXCL10, and higher D-dimer levels (P < .001). The area under the curve of the probability curve for predicting severe mycoplasma pneumonia is 0.975 (P < .05). Children with severe mycoplasma pneumonia have significantly longer fever duration and hospital stay than those with mild symptoms. The serum levels of CXCL10 and CXCL16 are significantly elevated.

Deep learning model for pleural effusion detection via active learning and pseudo-labeling: a multisite study.

BACKGROUND: The study aimed to develop and validate a deep learning-based Computer Aided Triage (CADt) algorithm for detecting pleural effusion in chest radiographs using an active learning (AL) framework. This is aimed at addressing the critical need for a clinical grade algorithm that can timely diagnose pleural effusion, which affects approximately 1.5 million people annually in the United States. METHODS: In this multisite study, 10,599 chest radiographs from 2006 to 2018 were retrospectively collected from an institution in Taiwan to train the deep learning algorithm. The AL framework utilized significantly reduced the need for expert annotations. For external validation, the algorithm was tested on a multisite dataset of 600 chest radiographs from 22 clinical sites in the United States and Taiwan, which were annotated by three U.S. board-certified radiologists. RESULTS: The CADt algorithm demonstrated high effectiveness in identifying pleural effusion, achieving a sensitivity of 0.95 (95% CI: [0.92, 0.97]) and a specificity of 0.97 (95% CI: [0.95, 0.99]). The area under the receiver operating characteristic curve (AUC) was 0.97 (95% DeLong's CI: [0.95, 0.99]). Subgroup analyses showed that the algorithm maintained robust performance across various demographics and clinical settings. CONCLUSION: This study presents a novel approach in developing clinical grade CADt solutions for the diagnosis of pleural effusion. The AL-based CADt algorithm not only achieved high accuracy in detecting pleural effusion but also significantly reduced the workload required for clinical experts in annotating medical data. This method enhances the feasibility of employing advanced technological solutions for prompt and accurate diagnosis in medical settings.

Early predictors of delayed radiographic resolution of lobar pneumonia caused by Mycoplasma pneumoniae in children: a retrospective study in China.

BACKGROUND: Lobar pneumonia caused by Mycoplasma pneumoniae is a relatively difficult-to-treat pneumonia in children. The time of radiographic resolution after treatment is variable, a long recovery time can result in several negative effects, and it has attracted our attention. Therefore, exploring factors associated with delayed radiographic resolution will help to identify these children at an early stage and prepare for early intervention. METHODS: The data of 339 children with lobar pneumonia caused by Mycoplasma pneumoniae were collected from the Department of Pediatrics of Fu Yang People's Hospital, China from January 2021 to June 2022. After discharge, the children were regularly followed up in the outpatient department and on the WeChat platform for > 8 weeks. According to whether pulmonary imaging (chest radiography or plain chest computed tomography) returned to normal within 8 weeks, the children were divided into the delayed recovery group (DRG) (n = 69) and the normal recovery group (NRG) (n = 270). The children's general information, laboratory examination findings, bronchoscopy results, and imaging findings were retrospectively analyzed. Single-factor analysis was performed to identify the risk factors for delayed radiographic resolution of lobar pneumonia caused by Mycoplasma pneumoniae, and the factors with statistically significant differences underwent multiple-factor logistic regression analysis. Receiver operating characteristic (ROC) analysis was then performed to calculate the cutoff value of early predictive indicators of delayed radiographic resolution. RESULTS: Single-factor analysis showed that the following were significantly greater in the DRG than NRG: total fever duration, the hospitalization time, C-reactive protein (CRP) level, lactate dehydrogenase (LDH) level, D-dimer level, pulmonary lesions involving two or more lobes, a large amount of pleural effusion, the time to interventional bronchoscopy, and mucus plugs formation. Multivariate logistic regression analysis showed that the hospitalization time, CRP level, LDH level, pulmonary lesions involving two or more lobes, and a large amount of pleural effusion were independent risk factors for delayed radiographic resolution of lobar pneumonia caused by Mycoplasma pneumoniae. The cutoff values on the receiver operating characteristic curve were a hospitalization time of ≥ 10.5 days, CRP level of ≥ 25.92 mg/L, and LDH level of ≥ 378 U/L. CONCLUSION: If patients with lobar pneumonia caused by Mycoplasma pneumoniae have a hospitalization time of ≥ 10.5 days, CRP level of ≥ 25.92 mg/L, and LDH level ≥ 378 U/L, the time of radiographic resolution is highly likely to exceed 8 weeks. Pediatricians must maintain a high level of vigilance for these factors, control the infection as early as possible, strengthen airway management, and follow up closely to avoid complications and sequelae of Mycoplasma pneumoniae pneumonia.

Analysis of invasive diagnostic techniques for pathological confirmation of pleural mesothelioma.

BACKGROUND AND OBJECTIVES: Mesothelioma is an infrequent neoplasm with a poor prognosis that is related to exposure to asbestos and whose peak incidence in Europe is estimated from 2020. Its diagnosis is complex; imaging techniques and the performance of invasive pleural techniques being essential for pathological confirmation. The different diagnostic yields of these invasive techniques are collected in the medical literature. The present work consisted of reviewing how the definitive diagnosis of mesothelioma cases in our centre was reached to check if there was concordance with the data in the bibliography. MATERIALS AND METHODS: Retrospective review of patients with a diagnosis of pleural mesothelioma in the period 2019-2021, analysing demographic data and exposure to asbestos, the semiology of the radiological findings and the invasive techniques performed to reach the diagnosis. RESULTS: Twenty-six mesothelioma cases were reviewed. 22 men and 4 women. Median age 74 years. 9 patients had a history of asbestos exposure. Moderate-severe pleural effusion was the most frequent radiological finding (23/26). The sensitivity of the invasive techniques was as follows: Cytology 13%, biopsy without image guidance 11%, image-guided biopsy 93%, surgical biopsy 67%. CONCLUSIONS: In our review, pleural biopsy performed with image guidance was the test that had the highest diagnostic yield, so it should be considered as the initial invasive test for the study of mesothelioma.

Eosinophilic Pleural Effusion Secondary to Trichinella spiralis Infection in a Patient with Systemic Sclerosis: A Case Report.

BACKGROUND Scleroderma is a chronic autoimmune disease characterized by angiopathy, autoimmunity, and fibrosis. One form of scleroderma, systemic sclerosis, is characterized by diffuse skin lesions and visceral involvement. Eosinophilic pleural effusion is a rare complication attributed to a large array of diseases. We present a case of a man with underlying systemic sclerosis who developed eosinophilic pleural effusion as a complication of associated Trichinella spiralis infection. CASE REPORT A 49-year-old man presented for bilateral inflammatory radio-ulnar-carpal joint pain, paresthesia of the hands and forearms and a 2-week history of right posterior aching thoracic pain and night sweats. The physical examination revealed sclerodermatous skin involvement of the hands, forearms, and forehead, sclerodactyly, Raynaud's phenomenon, and telangiectasias, together with muffled cardiac sounds and right basal abolishment of the vesicular breath sounds. Imagistic evaluation showed the presence of pleuro-pericardial fluid. A thoracocentesis highlighted the presence of an exudative eosinophilic pleural effusion. Laboratory findings showed leukocytosis, with elevated neutrophil and eosinophil counts. The patient was tested for a parasitic infection, but initially the results were negative. He started anti-inflammatory treatment, but no reduction of the pleural fluid was observed. Subsequent evaluation revealed specific anti-trichinella IgG antibodies. Albendazole and corticosteroid therapy were initiated, which resulted in remission of the symptoms. CONCLUSIONS This report highlights the possibility of developing rare or even not-until-now seen complications when 2 etiologically different diseases are associated. The physician should carefully assess the situation to find and resolve the underlying causes.

A Rare Cause of Empyema and Bacteremia Due to Shewanella Species in Alcoholic Cirrhosis Patients: A Case Report and Comprehensive Review of Literature.

BACKGROUND Shewanella spp. are gram-negative facultative anaerobic, oxidase-positive, motile bacilli that are ubiquitous but commonly occur in seawater and can cause opportunistic infection. Reports on the risk factors for Shewanella infection, its severity, antibiotic susceptibility, and prognosis are limited. This report is of a 78-year-old man with alcoholic cirrhosis presenting with bacteremia and empyema due to infection with Shewanella spp. CASE REPORT A 78-year-old man with alcoholic cirrhosis (Child-Pugh B) presented to our emergency room with a high fever. He had eaten raw fish one week prior to admission. Chest computed tomography showed a right unilateral pleural effusion, and he was hospitalized with suspected empyema. Shewanella spp. was detected in the pleural effusion and blood cultures. We initiated piperacillin/tazobactam and vancomycin empirically and switched to ceftriaxone; the effusion was successfully treated using antibiotics and pleural drainage. However, on hospitalization day 53, the patient died of aspiration pneumonia. In our literature review, we extracted 125 reported cases (including our case) and found that men were disproportionately affected (81%); median age was 61.6 (56-75) years; underlying diseases included hepatobiliary disease (33%), malignancy (25%), and cardiac disease (24%); Shewanella spp. infection sites were skin and soft tissue (35%), respiratory system (18%), and hepatobiliary system (11%); and management included antibiotics (100%), drainage (16%), and debridement (16%). The survival rate was 74% with antibiotics alone. CONCLUSIONS Our case highlights that clinicians should recognize Shewanella spp. as a cause of empyema and bacteremia in patients with liver cirrhosis, and that microbiological diagnosis with antibiotic sensitivity testing and treatment should be undertaken urgently to prevent fatal sepsis.

Role of NT-proBNP and lung ultrasound in diagnosing and classifying heart failure in a hospitalized oldest-old population: a cross-sectional study.

AIM: Diagnosing and classifying heart failure (HF) in the oldest-old patients has technical and interpretation issues, especially in the acute setting. We assessed the usefulness of both N-terminal pro-brain natriuretic peptide (NT-proBNP) and lung ultrasound (LUS) for confirming HF diagnosis and predicting, among hospitalized HF patients, those with reduced ejection fraction (HFrEF). METHODS: We performed a cross-sectional study on 148 consecutive patients aged ≥ 80 years admitted to our Internal Medicine and Geriatrics ward with at least one symptom/sign compatible with HF and NT-proBNP ≥ 125 pg/mL. We measured serum NT-proBNP levels and performed LUS and transthoracic echocardiography (TTE) on admission before diuretic therapy. We divided our cohort into three subgroups according to the left ventricular ejection fraction (LVEF): reduced (LVEF ≤ 40%), mildly-reduced (LVEF = 41-49%) and preserved (LVEF ≥ 50%). RESULTS: The mean age was 88±5 years. Male prevalence was 42%. Patients with HFrEF were 19%. Clinical features and laboratory parameters did not differ between the three subgroups, except for higher NT-proBNP in HFrEF patients, which also had a higher number of total B-lines and intercostal spaces of pleural effusion at LUS. Overall, NT-proBNP showed an inverse correlation with LVEF (r = -0.22, p = 0.007) and a direct correlation with age, total pulmonary B-lines, and intercostal spaces of pleural effusion. According to the ROCs, NT-proBNP levels, pulmonary B-lines and pleural effusion extension were poorly predictive for HFrEF. The best-performing cut-offs were 9531 pg/mL for NT-proBNP (SP 0.70, SE 0.50), 13 for total B-lines (SP 0.69, SE 0.85) and one intercostal space for pleural effusion (SP 0.55, SE 0.89). Patients with admission NT-proBNP ≥ 9531 pg/mL had a 2-fold higher risk for HFrEF (OR 2.5, 95% CI 1.3-4.9), while we did not find any association for total B-lines ≥ 13 or pleural effusion ≥ 1 intercostal space with HFrEF. A significant association with HFrEF emerged for the combination of NT-proBNP ≥ 9531 pg/mL, total B-lines ≥ 13 and intercostal spaces of pleural effusion ≥ 1 (adjusted OR 4.3, 95% CI 1.5-12.9). CONCLUSIONS: Although NT-proBNP and LUS help diagnose HF, their accuracy in discriminating HFrEF from non-HFrEF was poor in our real-life clinical study on oldest-old hospitalized patients, making the use of TTE still necessary to distinguish HF phenotypes in this peculiar setting. These data require confirmation in more extensive and longer prospective studies.

Benefit of intrapleural fibrinolytic therapy in the treatment of complicated parapneumonic effusion and empyema.

Our study aimed to assess the benefit of intrapleural fibrinolysis before resorting to surgery to treat complicated parapneumonic effusion and empyema. We conducted a retrospective and descriptive study, including all patients hospitalized in the intensive care unit (ICU) of the Abderhaman Mami hospital, Tunisia for empyema treated with instillation of intrapleural fibrinolytic therapy between the 1st January 2000 and 31st December 2016. In all patients, empyema was diagnosed on clinical features, imaging findings (chest X-ray, thoracic echography and/or computed tomography (CT), and microbiological data. The fibrinolytic agent used was streptokinase. The efficiency of intrapleural fibrinolytic therapy was judged on clinical and paraclinical results. Among 103 cases of complicated parapneumonic effusion and empyema, 34 patients were included. The mean age was 34 years [15-81] with a male predominance (sex ratio at 2.77). Median APACH II score was 9. Fifty (50%) of the patients (n=17) had no past medical history; addictive behavior was described in 17 patients (50%). All patients were admitted for acute respiratory failure and one patient for septic shock. Pleural effusion was bilateral in 7 patients. Bacteria isolated were Streptococcus pneumonia (6 cases), Staphylococcus aureus (3 cases, including one which methicillin-resistant), Staphylococcus epidermidis (1 case), anaerobes (5 cases), and Klebsiella pneumoniae (1 case). First-line antimicrobial drug therapy was amoxicillin-clavulanate in 20 patients. A chest drain was placed in all cases in the first 38 hours of ICU admission. The median number of fibrinolysis sessions was 4 [2-9] and the median term of drainage was 7 days [3-16]. No side effects were observed. Video-assisted thoracoscopic surgery was proposed in 5 patients. The median length of hospitalization stay was 15 days [6-31]. One patient died due to multi-organ failure.

Pleural fluid characteristics of patients with COVID-19 infection.

INTRODUCTION: Pleural effusions are known to occur in many cases of COVID-19. Data on typical characteristics of COVID-19-associated pleural effusions are limited. The goal of this project was to characterize the pleural fluid from patients with COVID-19. METHODS: We retrospectively collected electronic medical record data from adults hospitalized at a large metropolitan hospital system with COVID-19 infection who had a pleural effusion and a thoracentesis performed. We assessed pleural fluid characteristics and applied Light's criteria. RESULTS: We identified 128 effusions from 106 unique patients; 45.4% of the effusions had fluid/serum protein ratio greater than 0.5, 33.9% had fluid/serum lactate dehydrogenase (LDH) greater than 0.6, and 56.2% had fluid LDH greater than 2/3 of the serum upper limit of normal. Altogether, 68.5% of effusions met at least one of these three characteristics and therefore were exudative by Light's criteria. The white blood cell (WBC) differential was predominantly lymphocytic (mean 42.8%) or neutrophilic (mean 28.7%); monocytes (mean 12.7%) and eosinophils (mean 2.5%) were less common. CONCLUSION: We demonstrate that 68.5% of pleural effusions in patients with COVID-19 infection were exudative and hypothesize that COVID-19-associated pleural effusions are likely to be exudative with WBC differential more likely to be predominantly lymphocytic.

Lemierre syndrome with pulmonary empyema caused by Prevotella intermedia.

Lemierre syndrome is a rare disease that is most often caused by Fusobacterium necrophorum We present a case caused by Prevotella intermedia in a young, healthy man, complicated by multiple cavitary lung lesions, loculated pleural effusions requiring chest tube placement and trapezius abscess. Our case highlights (a) P. intermedia as a rare cause of Lemierre syndrome and (b) clinical response to appropriate antimicrobial therapy may be protracted.

Case report of parapneumonic effusion and mesothelial subdiaphragmatic cyst: relationship or coincidence?

Parapneumonic pleural effusions are common in patients with pneumonia. When colonized by pathogenic bacteria or other microorganisms, these effusions can progress to empyema. Additionally, empyema formation may result in extension of the infection into the infradiaphragmatic region, further complicating the clinical scenario. Many subphrenic collections are found to be mesothelial cysts, which are congenital in origin. However, data regarding the potential association between mesothelial diaphragmatic cysts and parapneumonic effusions are limited. We herein describe a toddler with pneumonia complicated by parapneumonic effusion and a lung abscess with a subphrenic collection. After abscess drainage and a full course of antibiotics, imaging revealed clear lung parenchyma with an interval resolution of the effusion and a persistent unchanged subphrenic collection that was confirmed to be mesothelial diaphragmatic cyst. This case highlights the fact that not every subphrenic collection associated with parapneumonic effusion is a communicated collection formed by seeding. Such a collection can instead be an incidental cyst, which is congenital in origin and known as a mesothelial diaphragmatic cyst. A diaphragmatic mesothelial cyst is an uncommon benign congenital cyst that is unrelated to an adjacent parapneumonic effusion. It is usually incidental and can be monitored without invasive intervention.

Comparative Analysis of CT Findings and Clinical Outcomes in Adult Patients With Disseminated and Localized Pulmonary Nocardiosis.

BACKGROUND: Pulmonary nocardiosis is a rare opportunistic infection with occasional systemic dissemination. This study aimed to investigate the computed tomography (CT) findings and prognosis of pulmonary nocardiosis associated with dissemination. METHODS: We conducted a retrospective analysis of patients diagnosed with pulmonary nocardiosis between March 2001 and September 2023. We reviewed the chest CT findings and categorized them based on the dominant CT findings as consolidation, nodules and/or masses, consolidation with multiple nodules, and nodular bronchiectasis. We compared chest CT findings between localized and disseminated pulmonary nocardiosis and identified significant prognostic factors associated with 12-month mortality using multivariate Cox regression analysis. RESULTS: Pulmonary nocardiosis was diagnosed in 75 patients, of whom 14 (18.7%) had dissemination, including involvement of the brain in 9 (64.3%) cases, soft tissue in 3 (21.4%) cases and positive blood cultures in 3 (21.4%) cases. Disseminated pulmonary nocardiosis showed a higher frequency of cavitation (64.3% vs. 32.8%, P = 0.029) and pleural effusion (64.3% vs. 29.5%, P = 0.014) compared to localized infection. The 12-month mortality rate was 25.3%. The presence of dissemination was not a significant prognostic factor (hazard ratio [HR], 0.80; confidence interval [CI], 0.23-2.75; P = 0.724). Malignancy (HR, 9.73; CI, 2.32-40.72; P = 0.002), use of steroid medication (HR, 3.72; CI, 1.33-10.38; P = 0.012), and a CT pattern of consolidation with multiple nodules (HR, 4.99; CI, 1.41-17.70; P = 0.013) were associated with higher mortality rates. CONCLUSION: Pulmonary nocardiosis with dissemination showed more frequent cavitation and pleural effusion compared to cases without dissemination, but dissemination alone did not affect the mortality rate of pulmonary nocardiosis.

Recurrent leishmaniasis infection isolated in the pleural fluid.

We present a rare case of recurrent leishmaniasis infection in a female in her 80s who re-presented with a pleural effusion. The patient was initially investigated as an outpatient for cytopenia and underwent a bone marrow biopsy which subsequently diagnosed visceral leishmaniasis. Following full treatment, and apparent recovery, she re-presented with pleural effusion, hypoalbuminaemia and cytopenia. Leishmania was eventually isolated in a pleural fluid sample obtained on therapeutic drainage, and she was treated for a recurrence at a tertiary infectious disease unit. This interesting and challenging case demonstrates the importance of suspecting leishmaniasis recurrence in previously treated cases and the diagnostic benefit of pleural fluid analysis in the context of suspected leishmaniasis.

Transcriptomic Profiling of Pleural Effusions: Differences in Malignant and Infectious Fluids.

Background and Objectives: Different cellular and molecular processes are involved in the production of malignant and infectious pleural effusions. However, the underlying mechanisms responsible for these differences or their consequences remain incompletely understood. The objective of this study was to identify differences in gene expression in pleural exudates of malignant and infectious aetiology and establish the possible different biological processes involved in both situations. Materials and Methods: RNA transcriptomic analysis was performed on 46 pleural fluid samples obtained during diagnostic thoracocenteses from 46 patients. There were 35 exudates (19 malignant and 16 infectious effusions) and 11 transudates that were used as a reference control group. Differential gene expression analysis for both exudative groups was identified. An enrichment score using the Human Kegg Orthology database was used for establishing the biological processes associated with malignant and infectious pleural effusions. Results: When comparing malignant exudates with infectious effusions, 27 differentially expressed genes with statistical significance were identified. Network analysis showed ten different biological processes for malignant and for infectious pleural effusions. In malignant fluids, processes related to protein synthesis and processing predominate. In infectious exudates, biological processes in connection with ATP production prevail. Conclusions: This study demonstrates differentially expressed genes in malignant and infectious pleural effusions, which could have important implications in the search for diagnostic or prognostic biomarkers. In addition, for the first time, biological processes involved in these two causes of pleural exudates have been described.

Pictorial Review of Pleural Disease: Multimodality Imaging and Differential Diagnosis.

The pleura is a thin, smooth, soft-tissue structure that lines the pleural cavity and separates the lungs from the chest wall, consisting of the visceral and parietal pleurae and physiologic pleural fluid. There is a broad spectrum of normal variations and abnormalities in the pleura, including pneumothorax, pleural effusion, and pleural thickening. Pneumothorax is associated with pulmonary diseases and is caused by iatrogenic or traumatic factors. Chest radiography and US help detect pneumothorax with various signs, and CT can also help assess the causes. Pleural effusion occurs in a wide spectrum of diseases, such as heart failure, cirrhosis, asbestos-related diseases, infections, chylothorax, and malignancies. Chest US allows detection of a small pleural effusion and evaluation of echogenicity or septa in pleural effusion. Pleural thickening may manifest as unilateral or bilateral and as focal, multifocal, or diffuse. Various diseases can demonstrate pleural thickening, such as asbestos-related diseases, neoplasms, and systemic diseases. CT, MRI, and fluorodeoxyglucose (FDG) PET/CT can help differentiate between benign and malignant lesions. Knowledge of these features can aid radiologists in suggesting diagnoses and recommending further examinations with other imaging modalities. The authors provide a comprehensive review of the clinical and multimodality imaging findings of pleural diseases and their differential diagnoses. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.