Correlación fisiopatológica, diagnóstica y terapéutica en el derrame pleural paraneumónico / Pathophysiological, diagnostic and therapeutic correlation in parapneumonic pleural effusion

Introducción: La inflamación de la pleura desencadenada por bacterias y mediada por citocinas, aumenta la permeabilidad vascular y produce vasodilatación, lo cual genera desequilibrio entre la producción de líquido pleural y su capacidad de reabsorción por eficientes mecanismos fisiológicos. La condición anterior conduce al desarrollo de derrame pleural paraneumónico. Objetivo: Exponer la importancia de la correlación fisiopatológica y diagnóstica con los pilares fundamentales de actuación terapéutica en el derrame pleural paraneumónico. Métodos: Revisión en PubMed y Google Scholar de artículos publicados hasta abril de 2021 que abordaran el derrame pleural paraneumónico, su fisiopatología, elementos diagnósticos, tanto clínicos como resultados del estudio del líquido pleural, pruebas de imágenes, y estrategias terapéuticas. Análisis y síntesis de la información: El progreso de una infección pulmonar y la producción de una invasión de gérmenes al espacio pleural favorece la activación de mecanismos que conllevan al acúmulo de fluido, depósito de fibrina y formación de septos. Este proceso patológico se traduce en manifestaciones clínicas, cambios en los valores citoquímicos y resultados microbiológicos en el líquido pleural, que acompañados de signos radiológicos y ecográficos en el tórax, guían la aplicación oportuna de los pilares de tratamiento del derrame pleural paraneumónico. Conclusiones: Ante un derrame pleural paraneumónico, con tabiques o partículas en suspensión en la ecografía de tórax, hallazgo de fibrina, líquido turbio o pus en el proceder de colocación del drenaje de tórax, resulta necesario iniciar fibrinólisis intrapleural. Cuando el tratamiento con fibrinolíticos intrapleurales falla, la cirugía video-toracoscópica es el procedimiento quirúrgico de elección(AU)

Introduction: The inflammation of the pleura triggered by bacteria and mediated by cytokines, increases vascular permeability and produces vasodilation, which generates imbalance between the production of pleural fluid and its resorption capacity by efficient physiological mechanisms. The above condition leads to the development of parapneumonic pleural effusion. Objective: To expose the importance of the pathophysiological and diagnostic correlation with the fundamental pillars of therapeutic action in parapneumonic pleural effusion. Methods: Review in PubMed and Google Scholar of articles published until April 2021 that addressed parapneumonic pleural effusion, its pathophysiology, diagnostic elements, both clinical and results of the pleural fluid study, imaging tests, and therapeutic strategies. Analysis and synthesis of information: The progress of a lung infection and the production of an invasion of germs into the pleural space favors the activation of mechanisms that lead to the accumulation of fluid, fibrin deposition and formation of septa. This pathological process results in clinical manifestations, changes in cytochemical values and microbiological results in the pleural fluid, which accompanied by radiological and ultrasound signs in the chest, guide the timely application of the pillars of treatment of parapneumonic pleural effusion. Conclusions: In the event of a parapneumonic pleural effusion, with septums or particles in suspension on chest ultrasound, finding fibrin, turbid fluid or pus in the procedure of placement of the chest drain, it is necessary to initiate intrapleural fibrinolytic. When treatment with intrapleural fibrinolytics fails, video-thoracoscopic surgery is the surgical procedure of choice(AU)

Diagnosing pleural effusions using mass spectrometry-based multiplexed targeted proteomics quantitating mid- to high-abundance markers of cancer, infection/inflammation and tuberculosis.

Pleural effusion (PE) is excess fluid in the pleural cavity that stems from lung cancer, other diseases like extra-pulmonary tuberculosis (TB) and pneumonia, or from a variety of benign conditions. Diagnosing its cause is often a clinical challenge and we have applied targeted proteomic methods with the aim of aiding the determination of PE etiology. We developed a mass spectrometry (MS)-based multiple reaction monitoring (MRM)-protein-panel assay to precisely quantitate 53 established cancer-markers, TB-markers, and infection/inflammation-markers currently assessed individually in the clinic, as well as potential biomarkers suggested in the literature for PE classification. Since MS-based proteomic assays are on the cusp of entering clinical use, we assessed the merits of such an approach and this marker panel based on a single-center 209 patient cohort with established etiology. We observed groups of infection/inflammation markers (ADA2, WARS, CXCL10, S100A9, VIM, APCS, LGALS1, CRP, MMP9, and LDHA) that specifically discriminate TB-PEs and other-infectious-PEs, and a number of cancer markers (CDH1, MUC1/CA-15-3, THBS4, MSLN, HPX, SVEP1, SPINT1, CK-18, and CK-8) that discriminate cancerous-PEs. Some previously suggested potential biomarkers did not show any significant difference. Using a Decision Tree/Multiclass classification method, we show a very good discrimination ability for classifying PEs into one of four types: cancerous-PEs (AUC: 0.863), tuberculous-PEs (AUC of 0.859), other-infectious-PEs (AUC of 0.863), and benign-PEs (AUC: 0.842). This type of approach and the indicated markers have the potential to assist in clinical diagnosis in the future, and help with the difficult decision on therapy guidance.

Parapneumonic Effusions Are Characterized by Elevated Levels of Neutrophil Extracellular Traps.

BACKGROUND: Neutrophil extracellular traps (NETs) increasingly are implicated in acute and chronic conditions involving multiple organ systems. RESEARCH QUESTION: Are NET concentrations higher in parapneumonic effusions compared with effusions of other origin and does this reflect the inflammatory nature of these effusions? STUDY DESIGN AND METHODS: Patients (N = 101) seeking hospital treatment for undifferentiated pleural effusion underwent pleural fluid classification based on cytologic analysis results, biochemical findings, microbiological characteristics, and clinical judgement. Concentrations of NET markers (extracellular DNA [eDNA], citrullinated histone H3 [citH3]), neutrophils (α-defensins), and inflammation (IL-1ß)-related proteins were quantified by enzyme-linked immunosorbent assay. Differences between groups were analyzed using the Kruskal-Wallis one-way analysis of variance. Correlations used Spearman coefficient. Receiver operating characteristic (ROC) curves were calculated. RESULTS: Effusions were classified into four groups: parapneumonic (n = 18), malignant (n = 35), transudative (n = 22), and unclassifiable (n = 26). Concentrations of NETs markers were significantly higher in the parapneumonic group compared with malignant, transudative, and unclassifiable groups (median eDNA, 12.8 ng/mL vs 0.77 ng/mL, 0.44 ng/mL, and 0.86 ng/mL [P < .001]; and median citH3, 127.1 ng/mL vs 0.44 ng/mL, 0.34 ng/mL, and 0.49 ng/mL [P < .001]). citH3 and eDNA were correlated highly with lactate dehydrogenase (LDH; Spearman r = 0.66 and r = 0.73, respectively; P < .001) and moderately negatively correlated with pH (r = -0.55 and r = -0.62, respectively; P < .001). α-Defensins and IL-1ß were higher in the parapneumonic group than in other groups (median α-defensins, 124.4 ng/mL vs 4.7 ng/mL,7 ng/mL, and 6.9 ng/mL [P < .001]; and median IL-1ß, 145 pg/mL vs 1.87 pg/mL, 1.39 pg/mL, and 2.6 pg/mL [P < .001]) and moderately correlated with LDH (r = 0.60 and r = 0.57; P < .001). ROC curves showed high sensitivity and specificity for NET markers for prediction of parapneumonic effusion. INTERPRETATION: High levels of some NET-related mediators in parapneumonic effusions correlate with inflammation. Effusions of other causes do not show high levels of NETs. These results may have treatment implications because NETs may be an important contributor to the inflammation and viscosity of parapneumonic effusions and may help us to understand the therapeutic benefit of deoxyribonuclease in empyema.

Cuban Experience with Lung Ultrasound to Diagnose and Classify Pleural Effusion in Critically Ill Patients.

Pleural effusion is a common condition in critically ill patients (both clinical and surgical). Its diagnosis and classification are important for followup of patients with cardiorespiratory difficulty. Lung ultrasound is used for this purpose, but no reports have been published on its use in Cuba with critically ill patients in intensive care units. We performed lung ultrasound on 144 such patients with cardiorespiratory illnesses, average age 54 years, predominantly men (66%; 95/144), with average APACHE II score 13.6, and 22.1% mortality risk. Patients were divided into two groups: clinical (bronchopneumonia and cardiac insufficiency) and surgical (postoperative liver and kidney transplant or vascular and cardiovascular surgery) to diagnose and classify pleural effusion according to locus (right, left and bilateral) and structural pattern (I, II A, II B, III and IV). Pleural effusions were diagnosed in 81.2% (117/144) of patients (clinical 44.4%, 52/117; surgical 55.6%, 65/117). Bilateral location was the most common (68.4%, 80/117), followed by right (23.9%, 28/117) and then left (7.7%, 9/117). Structural pattern I (anechoic appearance) was observed in 61.5% of cases (72/117); 21.4% (25/117) were II A, 12.8% (15/117) II B, 3.4% (4/117) III, and 0.9% (1/117) were IV. We found no association between pleural effusion localization and ultrasound structural pattern in clinical patients (Fisher exact test 4.2 p = 0.9). In surgical patients, however, complex ultrasound patterns (II A, II B and III) were significantly more common in bilateral forms (Fisher exact test 14.1; p = 0.009). Further studies of this type in Cuba will help provide useful data for prompt treatment and followup of these patients.

Diagnosis of malignant pleural mesothelioma from pleural fluid by Fourier transform-infrared spectroscopy coupled with chemometrics.

This study was conducted to differentiate malignant pleural mesothelioma (MPM) from lung cancer (LC) and benign pleural effusion (BPE) from pleural fluids using the diagnostic power of Fourier transform-infrared spectroscopy with attenuated total reflectance mode coupled with chemometrics. Infrared spectra of MPM (n = 24), LC (n = 20), and BPE (n = 25) were collected, and hierarchical cluster analysis (HCA) and principal component analysis (PCA) were applied to their spectra. HCA results indicated that MPM was differentiated from LC with 100% sensitivity and 100% specificity and from BPE, with 100% sensitivity and 88% specificity, which were also confirmed by PCA score plots. PCA loading plots indicated that these separations originated mainly from lipids, proteins, and nucleic acids-related spectral bands. There was significantly higher lipid, protein, nucleic acid, and glucose contents in the MPM and LC. However, the significant changes in triglyceride and cholesterol ester content, protein and nucleic acid structure, a lower membrane fluidity, and higher membrane order were only observed in the MPM. To check the classification success of some test samples/each group, soft independent modeling of class analogies was performed and 96.2% overall classification success was obtained. This approach can provide a rapid and inexpensive methodology for the efficient differentiation of MPM from other pleural effusions.

The impact of between analytical platform variability on the classification of pleural effusions into exudate or transudate using Light's criteria.

BACKGROUND: Light's criteria are ratios of pleural fluid to serum total protein (TP), pleural fluid to serum lactate dehydrogenase (LDH) and pleural fluid LDH to the upper reference limit for serum LDH. They are used to classify pleural effusions into an exudate or transudate when pleural fluid protein is 25-35 g/L. We evaluated the impact of between analytical platforms on the classification of pleural effusions using Light's criteria. METHODS: Light's criteria were used to classify pleural effusions with fluid TP between 25 and 35 g/L into exudate and transudate. LDH and TP were analysed using an Abbott ARCHITECT c16000 analyser using a lactate to pyruvate method for LDH and two Roche Cobas 800 c702 analysers, one using a lactate to pyruvate method (laboratory B) and one a lactate to pyruvate method (laboratory C). RESULTS: Eighty-three paired serum and pleural fluid samples were analysed. Of these, 44 samples had a pleural fluid TP between 25 and 35 g/L and were classified according to Light's criteria. Classification of pleural fluid into transudate or exudate using different analytical platforms was 82% concordant. The LDH ratio and TP ratio were similar in laboratory B and laboratory C, but these were respectively lower (p<0.001) and higher (p<0.001) than those at laboratory A. CONCLUSIONS: Although Light's criteria are ratios, which should minimise interassay variability, we report 18% discordance between different analytical platforms. The discordance was largely due to the performance of LDH and to a lesser extent protein assays in pleural fluid. Laboratories should be aware that assays may perform differently in serum and pleural fluid.

A Multiplexed Cytokeratin Analysis Using Targeted Mass Spectrometry Reveals Specific Profiles in Cancer-Related Pleural Effusions.

Pleural effusion (PE), excess fluid in the pleural space, is often observed in lung cancer patients and also forms due to many benign ailments. Classifying it quickly is critical, but this remains an analytical challenge often lengthening the diagnosis process or exposing patients to unnecessary risky invasive procedures. We tested the analysis of PE using a multiplexed cytokeratin (CK) panel with targeted mass spectrometry-based quantitation for its rapid classification. CK markers are often assessed in pathological examinations for cancer diagnosis and guiding treatment course. We developed methods to simultaneously quantify 33 CKs in PE using peptide standards for increased analytical specificity and a simple CK enrichment method to detect their low amounts. Analyzing 121 PEs associated with a variety of lung cancers and noncancerous causes, we show that abundance levels of 10 CKs can be related to PE etiology. CK-6, CK-7, CK-8, CK-18, and CK-19 were found at significantly higher levels in cancer-related PEs. Additionally, elevated levels of vimentin and actin differentiated PEs associated with bacterial infections. A classifier algorithm effectively grouped PEs into cancer-related or benign PEs with 81% sensitivity and 79% specificity. A set of undiagnosed PEs showed that our method has potential to shorten PE diagnosis time. For the first time, we show that a cancer-relevant panel of simple-epithelial CK markers currently used in clinical assessment can also be quantitated in PEs. Additionally, while requiring less invasive sampling, our methodology demonstrated a significant ability to identify cancer-related PEs in clinical samples and thus could improve patient care in the future.

The Diagnostic Value of the Pleural Fluid C-Reactive Protein in Parapneumonic Effusions.

Purpose. The aim of this study was to evaluate the sensitivity of pleural C-reactive protein (CRP) biomarker levels in identifying parapneumonic effusions. Methods. A single-center, retrospective review of 244 patients diagnosed with pleural effusions was initiated among patients at the Rabin Medical Center, Petah Tikva, Israel, between January 2011 and December 2013. The patients were categorized into 4 groups according to their type of pleural effusion as follows: heart failure, malignant, post-lung transplantation, and parapneumonic effusion. Results. The pleural CRP levels significantly differentiated the four groups (p < 0.001) with the following means: parapneumonic effusion, 5.38 ± 4.85 mg/dL; lung transplant, 2.77 ± 2.66 mg/dL; malignancy, 1.19 ± 1.51 mg/dL; and heart failure, 0.57 ± 0.81 mg/dL. The pleural fluid CRP cut-off value for differentiating among parapneumonic effusions and the other 3 groups was 1.38 mg/dL. The sensitivity, specificity, positive predictive value, and negative predictive value were 84.2%, 71.5%, 37%, and 95%, respectively. A backward logistic regression model selected CRP as the single predictor of parapneumonic effusion (OR = 1.59, 95% CI = 1.37-1.89). Conclusions. Pleural fluid CRP levels can be used to distinguish between parapneumonic effusions and other types of exudative effusions. CRP levels < 0.64 mg/dL are likely to indicate a pleural effusion from congestive heart failure, whereas levels ≥ 1.38 mg/dL are suggestive of an infectious etiology.

Proteomic study of benign and malignant pleural effusion.

BACKGROUND: Lung adenocarcinoma can easily cause malignant pleural effusion which was difficult to discriminate from benign pleural effusion. Now there was no biomarker with high sensitivity and specificity for the malignant pleural effusion. PURPOSE: This study used proteomics technology to acquire and analyze the protein profiles of the benign and malignant pleural effusion, to seek useful protein biomarkers with diagnostic value and to establish the diagnostic model. METHODS: We chose the weak cationic-exchanger magnetic bead (WCX-MB) to purify peptides in the pleural effusion, used matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) to obtain peptide expression profiles from the benign and malignant pleural effusion samples, established and validated the diagnostic model through a genetic algorithm (GA) and finally identified the most promising protein biomarker. RESULTS: A GA diagnostic model was established with spectra of 3930.9 and 2942.8 m/z in the training set including 25 malignant pleural effusion and 26 benign pleural effusion samples, yielding both 100 % sensitivity and 100 % specificity. The accuracy of diagnostic prediction was validated in the independent testing set with 58 malignant pleural effusion and 34 benign pleural effusion samples. Blind evaluation was as follows: the sensitivity was 89.6 %, specificity 88.2 %, PPV 92.8 %, NPV 83.3 % and accuracy 89.1 % in the independent testing set. The most promising peptide biomarker was identified successfully: Isoform 1 of caspase recruitment domain-containing protein 9 (CARD9), with 3930.9 m/z, was decreased in the malignant pleural effusion. CONCLUSIONS: This model is suitable to discriminate benign and malignant pleural effusion and CARD9 can be used as a new peptide biomarker.

Enfoque diagnóstico en el paciente con derrame pleural / Diagnostic approach in pleural effusion

En el estudio diagnóstico del paciente con derrame pleural se deben considerar la historia clínica y el análisis de las imágenes para acotar el diagnóstico diferencial. El uso adecuado de las técnicas de imágenes contribuye a realizar procedimientos en forma segura. Se debe realizar una toracocentesis diagnóstica y/o evacuadora y se debe analizar completamente el líquido pleural. A veces es necesario realizar biopsia pleural para lo cual existen diversas técnicas disponibles. En los pacientes con pleuritis crónica inespecífica se debe hacer seguimiento por dos años para evaluar el desarrollo de malignidad.

The diagnostic approach in patients with pleural effusion must begin considering clinical aspects and image interpretation. Different imaging techniques can safely guide invasive procedures. Diagnostic or therapeutic thoracentesis must be performed and pleural fluid must be completely analyzed. Some patient will require pleural biopsy, and different techniques are available. Patients with chronic unspecific pleuritis histological diagnosis after pleural biopsy, must be followed for two years long to be sure no malignancy is developed.

[Parapneumonic pleural effusions: Epidemiology, diagnosis, classification and management]. / Les épanchements pleuraux parapneumoniques: épidémiologie, diagnostic, classification, traitement.

Parapneumonic pleural effusions represent the main cause of pleural infections. Their incidence is constantly increasing. Although by definition they are considered to be a "parapneumonic" phenomenon, the microbial epidemiology of these effusions differs from pneumonia with a higher prevalence of anaerobic bacteria. The first thoracentesis is the most important diagnostic stage because it allows for a distinction between complicated and non-complicated parapneumonic effusions. Only complicated parapneumonic effusions need to be drained. Therapeutic evacuation modalities include repeated therapeutic thoracentesis, chest tube drainage or thoracic surgery. The choice of the first-line evacuation treatment is still controversial and there are few prospective controlled studies. The effectiveness of fibrinolytic agents is not established except when they are combined with DNase. Antibiotics are mandatory; they should be initiated as quickly as possible and should be active against anaerobic bacteria except for in the context of pneumococcal infections. There are few data on the use of chest physiotherapy, which remains widely used. Mortality is still high and is influenced by underlying comorbidities.

Diagnostic value of soluble receptor-binding cancer antigen expressed on SiSo cells and carcinoembryonic antigen in malignant pleural effusion in patients with lung cancer.

AIM: The aim of this study was to evaluate the diagnostic value of soluble receptor-binding cancer antigen expressed on SiSo cells (sRCAS1) and carcinoembryonic antigen (CEA) in lung cancer patients with malignant pleural effusion (MPE) and benign pleural effusion (BPE). METHODS: Pleural effusion samples from 118 patients were classified on the basis of diagnosis as MPE (n=60) and BPE (n=58). The concentration of sRCAS1 was determined by enzyme-linked immunosorbent assay. The CEA levels were also determined in all patients. RESULTS: Of 60 MPE patients, 50 had sRCAS1>9.7 U/mL and 54 had CEA>5.5 ng/mL. The concentration of both sRCAS1 and CEA in MPE was significantly higher compared with that in BPE (P<0.01 in both cases). With a cutoff point of 9.7 U/mL, sRCAS1 had a sensitivity of 83.3% and a specificity of 91.4% for differential diagnosis. The combined detection of sRCAS1 and CEA had a sensitivity of 98.3% and a specificity of 96.6% to distinguish MPE from BPE. CONCLUSION: The combined detection of sRCAS1 and CEA may be more valuable in the differential diagnosis between MPE and BPE.

Assessment of circulating N-terminal pro B-type natriuretic peptide concentration to differentiate between cardiac from noncardiac causes of pleural effusion in cats.

OBJECTIVE: To determine the diagnostic ability of blood N-terminal pro B-type natriuretic peptide (NT-proBNP) measurement to differentiate between congestive heart failure (CHF) and noncardiogenic causes for moderate to severe pleural effusion in cats. DESIGN: Prospective observational study. SETTING: University teaching hospital. ANIMALS: Twenty-one cats with moderate to severe pleural effusion. INTERVENTIONS: Venous blood sampling for NT-proBNP measurement. MEASUREMENT AND RESULTS: According to the results of echocardiographic examination, cats were classified in a group with CHF (n = 11) or noncongestive heart failure (N-CHF, n = 10). NT-proBNP was measured via a feline-specific test in EDTA plasma with protease inhibitor. NT-proBNP was significantly (P < 0.0001) higher in the CHF group ( median 982 pmol/L, 355-1,286 pmol/L) than in the N-CHF group (median 69 pmol/L, 26 - 160 pmol/L) and discriminated exactly (area under the curve = 1.0, 95% confidence interval 1.0-1.0) between both groups. Optimum cut-off value considering all samples was 258 pmol/L. CONCLUSION: In this small population of cats with pleural effusion, NT-proBNP was able to differentiate between cats with cardiogenic and noncardiogenic causes of effusion. With the currently recommended method of measurement (ie, EDTA plasma with protease inhibitor), a cut-off value of 258 pmol/L discriminates effectively between cats with and without CHF.

A new, simple method for estimating pleural effusion size on CT scans.

BACKGROUND: There is no standardized system to grade pleural effusion size on CT scans. A validated, systematic grading system would improve communication of findings and may help determine the need for imaging guidance for thoracentesis. METHODS: CT scans of 34 patients demonstrating a wide range of pleural effusion sizes were measured with a volume segmentation tool and reviewed for qualitative and simple quantitative features related to size. A classification rule was developed using the features that best predicted size and distinguished among small, moderate, and large effusions. Inter-reader agreement for effusion size was assessed on the CT scans for three groups of physicians (radiology residents, pulmonologists, and cardiothoracic radiologists) before and after implementation of the classification rule. RESULTS: The CT imaging features found to best classify effusions as small, moderate, or large were anteroposterior (AP) quartile and maximum AP depth measured at the midclavicular line. According to the decision rule, first AP-quartile effusions are small, second AP-quartile effusions are moderate, and third or fourth AP-quartile effusions are large. In borderline cases, AP depth is measured with 3-cm and 10-cm thresholds for the upper limit of small and moderate, respectively. Use of the rule improved interobserver agreement from κ = 0.56 to 0.79 for all physicians, 0.59 to 0.73 for radiology residents, 0.54 to 0.76 for pulmonologists, and 0.74 to 0.85 for cardiothoracic radiologists. CONCLUSIONS: A simple, two-step decision rule for sizing pleural effusions on CT scans improves interobserver agreement from moderate to substantial levels.

Identifying transudates misclassified by Light's criteria.

PURPOSE OF REVIEW: Light's criteria combine three dichotomous tests into a decision rule that is considered positive if any one of the tests is positive. This strategy clearly maximizes sensitivity, although at the expense of specificity. Although Light's criteria identify 98% of pleural exudates, they misclassify about 25% of transudates as exudates. The way to overcome this limitation is discussed in this review. RECENT FINDINGS: Traditionally, measurement of the protein gradient between the serum and pleural fluid has been recommended to decrease the misclassification rate of Light's criteria. A recent study demonstrated that a gradient between the albumin levels in the serum and the pleural fluid more than 1.2 g/dl performs significantly better than a protein gradient more than 3.1 g/dl to correctly categorize mislabeled cardiac effusions (83 vs. 55%). On the other hand, the accuracy of a pleural fluid to serum albumin ratio less than 0.6 excelled when compared with albumin and protein gradients in patients with miscategorized hepatic hydrothoraces (77 vs. 62 vs. 61%). SUMMARY: The simplest strategy to reveal the true transudative nature of heart failure-related effusions, labeled as exudates by Light's criteria, is to calculate the serum to pleural fluid albumin gradient. Conversely, for misclassified hepatic hydrothoraces, measurement of the pleural to serum albumin ratio is recommended. The serum to pleural fluid protein gradient should no longer be considered the preferred test for this purpose.

Treatment of complicated parapneumonic pleural effusion and pleural parapneumonic empyema.

BACKGROUND: We performed this observational prospective study to evaluate the results of the application of a diagnostic and therapeutic algorithm for complicated parapneumonic pleural effusion (CPPE) and pleural parapneumonic empyema (PPE). MATERIAL/METHODS: From 2001 to 2007, 210 patients with CPPE and PPE were confirmed through thoracocentesis and treated with pleural drainage tubes (PD), fibrinolytic treatment or surgical intervention (videothoracoscopy and posterolateral thoracotomy). Patients were divided into 3 groups: I (PD); II (PD and fibrinolytic treatment); IIIa (surgery after PD and fibrinolysis), and IIIb (direct surgery). The statistical study was done by variance analysis (ANOVA), χ2 and Fisher exact test. RESULTS: The presence of alcohol or drug consumption, smoking and chronic obstructive pulmonary disease (COPD) were strongly associated with a great necessity for surgical treatment. The IIIa group was associated with increased drainage time, length of stay and complications. No mortality was observed. The selective use of PD and intrapleural fibrinolysis makes surgery unnecessary in more than 75% of cases. CONCLUSIONS: The selective use of PD and fibrinolysis avoids surgery in more than 75% of cases. However, patients who require surgery have more complications, longer hospital stay, and more days on PD and they are more likely to require admittance to the Intensive Care Unit.

Estudo do líquido pleural: uma revisão / Pleural effusion study: a review

O acúmulo de líquidos em cavidades fechadas do organismo chama-se derrame cavitário. A efusão pleural é o derrame patológico de líquido na cavidade formada pelas membranas mesoteliais que revestem os pulmões. Causas diversas podem originarestes derrames. Transudatos e exsudatos são classificações preliminares de efusões pleurais de acordo com alguns caracteresfísico-químicos. Transudatos possuem LDH, proteínas e celularidade menores do que os exsudatos. Culturas para anaeróbios, micobactérias e fungos são solicitadas de acordo com a suspeita clínica e epidemiológica. Dosagens bioquímicas e de marcadores tumorais assim como o estudo citológico, microbiológico e de biologia molecular são bastante úteis para o esclarecimento das causas dos derrames pleurais.

The accumulation of fluid in the closed cavities of the body is called spill cavity. The pleural effusion is the pathologicalspill of liquid into the cavity formed by mesotelials membranes, which recover the lungs. Many causes can origin these various spills. Transudates and exudates are preliminary classifications of pleural effusions according to some physical and chemical characteristics. Transudates have LDH, proteins and cellularity lower than the exsudates. Cultures for anaerobics, mycobacteriaand fungi are invited according to epidemiological and clinical suspicion. Biochemical and tumor markers doses rates and so the cytologic study, microbiological study and molecular biology are very helpful to clarify the causes of pleural effusions.