Pleural Fluid Analysis: Are Light's Criteria Still Relevant After Half a Century?

Fifty years from their initial description, Light's criteria are still unhesitatingly accepted as the default reference test for separating pleural transudates and exudates. Efforts should be focused not so much on trying to find an even more reliable technique for categorizing PEs but on improving the misclassification rate of transudates that characterize Light's criteria. Despite their shortcomings, Light's criteria may well continue their reign for another 50 years. Long live the Light's criteria!

The Legend of the Buffalo Chest.

BACKGROUND: The "buffalo chest" is a condition in which a simultaneous bilateral pneumothorax occurs due to a communication of both pleural cavities caused by an iatrogenic or idiopathic fenestration of the mediastinum. This rare condition is known by many clinicians because of a particular anecdote which stated that Native Americans could kill a North American bison with a single arrow in the chest by creating a simultaneous bilateral pneumothorax, due to the animal's peculiar anatomy in which there is one contiguous pleural space due to an incomplete mediastinum. RESEARCH QUESTION: What evidence is there for the existence of buffalo chest? STUDY DESIGN AND METHODS: The term "buffalo chest" and its anecdote were first mentioned in a ''personal communication'' by a veterinarian in the Annals of Surgery in 1984. A mixed method research was performed on buffalo chest and its etiology. A total of 47 cases of buffalo chest were identified in humans. RESULTS: This study found that all authors were referring to the article from 1984 or to each other. Evidence was found for interpleural communications in other mammal species, but no literature on the anatomy of the mediastinum of the bison was found. The main reason for this research was fact-checking the origin of the anecdote and search for evidence for the existence of buffalo chest. Autopsies were performed on eight bison, and four indeed were found to have had interpleural communications. INTERPRETATION: We hypothesize that humans can also have interpleural fenestrations, which can be diagnosed when a pneumothorax occurs.

Management of Indwelling Tunneled Pleural Catheters: A Modified Delphi Consensus Statement.

BACKGROUND: The management of recurrent pleural effusions remains a challenging issue for clinicians. Advances in management have led to increased use of indwelling tunneled pleural catheters (IPC) because of their effectiveness and ease of outpatient placement. However, with the increase in IPC placement there have also been increasing reports of complications, including infections. Currently there is minimal guidance in IPC-related management issues after placement. RESEARCH QUESTION: Our objective was to formulate clinical consensus statements related to perioperative and long-term IPC catheter management based on a modified Delphi process from experts in pleural disease management. STUDY DESIGN AND METHODS: Expert panel members used a modified Delphi process to reach consensus on common perioperative and long-term management options related to IPC use. Members were identified from multiple countries, specialties, and practice settings. A series of meetings and anonymous online surveys were completed. Responses were used to formulate consensus statements among panel experts, using a modified Delphi process. Consensus was defined a priori as greater than 80% agreement among panel constituents. RESULTS: A total of 25 physicians participated in this project. The following topics were addressed during the process: definition of an IPC infection, management of IPC-related infectious complications, interventions to prevent IPC infections, IPC-related obstruction/malfunction management, assessment of IPC removal, and instructions regarding IPC management by patients and caregivers. Strong consensus was obtained on 36 statements. No consensus was obtained on 29 statements. INTERPRETATION: The management of recurrent pleural disease with IPC remains complex and challenging. This statement offers statements for care in numerous areas related to IPC management based on expert consensus and identifies areas that lack consensus. Further studies related to long-term management of IPC are warranted.

The Impact of Gravity vs Suction-driven Therapeutic Thoracentesis on Pressure-related Complications: The GRAVITAS Multicenter Randomized Controlled Trial.

BACKGROUND: Thoracentesis can be accomplished by active aspiration or drainage with gravity. This trial investigated whether gravity drainage could protect against negative pressure-related complications such as chest discomfort, re-expansion pulmonary edema, or pneumothorax compared with active aspiration. METHODS: This prospective, multicenter, single-blind, randomized controlled trial allocated patients with large free-flowing effusions estimated ≥ 500 mL 1:1 to undergo active aspiration or gravity drainage. Patients rated chest discomfort on 100-mm visual analog scales prior to, during, and following drainage. Thoracentesis was halted at complete evacuation or for persistent chest discomfort, intractable cough, or other complication. The primary outcome was overall procedural chest discomfort scored 5 min following the procedure. Secondary outcomes included measures of discomfort and breathlessness through 48 h postprocedure. RESULTS: A total of 142 patients were randomized to undergo treatment, with 140 in the final analysis. Groups did not differ for the primary outcome (mean visual analog scale score difference, 5.3 mm; 95% CI, -2.4 to 13.0; P = .17). Secondary outcomes of discomfort and dyspnea did not differ between groups. Comparable volumes were drained in both groups, but the procedure duration was significantly longer in the gravity arm (mean difference, 7.4 min; 95% CI, 10.2 to 4.6; P < .001). There were no serious complications. CONCLUSIONS: Thoracentesis via active aspiration and gravity drainage are both safe and result in comparable levels of procedural comfort and dyspnea improvement. Active aspiration requires less total procedural time. TRIAL REGISTRY: ClinicalTrials.gov; No.: NCT03591952; URL: www.clinicaltrials.gov.

Pleuroscopy or video-assisted thoracoscopic surgery for exudative pleural effusion: a comparative overview.

Exudative pleural effusions, such as malignant and tuberculous pleural effusions, are associated with notable morbidity and mortality. Unfortunately, a significant number of these effusions will remain undiagnosed despite thoracentesis. Traditionally, closed pleural biopsies have been the next best diagnostic step, but the diagnostic yield of blind closed pleural biopsies for malignant pleural effusions is insufficient. When image-guided targeted biopsies are not possible, both pleuroscopy and video-assisted thoracoscopic surgery are reasonable options for obtaining pleural biopsies, but the decision to select one procedure over the other continues to raise much debate. Pleuroscopy (aka. medical thoracoscopy, local anaesthetic thoracoscopy) is a relatively common procedure performed by interventional pulmonologists in the bronchoscopy suite with local anesthesia, often as an outpatient procedure, on spontaneously breathing patients. Video-assisted thoracoscopic surgery, on the other hand, is performed by thoracic surgeons in the operating room, on mechanically ventilated patients under general anesthesia, though admittedly considerable overlap exists in practice. Both pleuroscopy and video-assisted thoracoscopic surgery have reported diagnostic yields of over 90%, although pleuroscopy more often leads to the unsatisfactory diagnosis of 'non-specific' pleuritis. These cases of 'non-specific' pleuritis need to be followed up for at least one year, as 10-15% of them will eventually lead to the diagnosis of cancer, typically malignant pleural mesothelioma. Both procedures have their pros and cons, and it is therefore of paramount importance that all cases be discussed as part of a multidisciplinary approach to diagnosis within a "pleural team" that should ideally include interventional pulmonologists and thoracic surgeons.

Phase 1 trial of intrapleural LTI-01; single chain urokinase in complicated parapneumonic effusions or empyema.

BACKGROUND: Current dosing of intrapleural fibrinolytic therapy (IPFT) in adults with complicated parapneumonic effusion (CPE) / empyema is empiric, as dose-escalation trials have not previously been conducted. We hypothesized that LTI-01 (scuPA), which is relatively resistant to PA inhibitor-1 (PAI-1), would be well-tolerated. METHODS: This was an open-label, dose-escalation trial of LTI-01 IPFT at 50,000-800,000 IU daily for up to 3 days in adults with loculated CPE/empyema and failed pleural drainage. The primary objective was to evaluate safety and tolerability, and secondary objectives included assessments of processing and bioactivity of scuPA in blood and pleural fluid (PF), and early efficacy. RESULTS: LTI-01 was well tolerated with no bleeding, treatment-emergent adverse events or surgical referrals (n=14 subjects). uPA antigen increased in PFs at 3 hours after LTI-01 (p<0.01) but not in plasma. PF saturated active PAI-1, generated PAI-1-resistant bioactive complexes, increased PA and fibrinolytic activities and D-dimers. There was no systemic fibrinogenolysis, nor increments in plasma D-dimer. Decreased pleural opacities occurred in all but one subject. Both subjects receiving 800,000 IU required two doses to relieve pleural sepsis, with two other subjects similarly responding at lower doses. CONCLUSION: LTI-01 IPFT was well-tolerated at these doses with no safety concerns. Bioactivity of LTI-01 IPFT was confirmed, limited to PFs where its processing simulated that previously reported in preclinical studies. Preliminary efficacy signals including reduction of pleural opacity were observed.

A novel diagnostic method for distinguishing parapneumonic effusion and empyema from other diseases by using the pleural lactate dehydrogenase to adenosine deaminase ratio and carcinoembryonic antigen levels.

Pleural effusions are a common medical problem not only for pulmonologists but also for general physicians, often needing thoracentesis for a definite diagnosis. However, thoracentesis cannot always reveal malignant cells or microbiological evidence.In this context, we prospectively enrolled a total of 289 patients with pleural effusions due to diverse etiologies: parapneumonic effusion (PPE) (63), empyema (22), tuberculous pleural effusion (TBPE) (54), malignant pleural effusion (MPE) (140), or chronic renal failure (CRF)/congestive heart failure (CHF) (10). The MPE group consisted of lung cancer (adenocarcinoma, n = 90; squamous cell carcinoma, n = 5; small cell carcinoma, n = 4), malignant lymphoma (n = 17), malignant mesothelioma (n = 11), malignant melanoma (n = 3), and metastasis from other organs (n = 10).This study demonstrated that the pleural lactate dehydrogenase (LDH)to adenosine deaminase (ADA) ratios differed significantly between patients with CHF/CRF, MPE, TBPE, empyema, and PPE. We discovered a simple method to differentiate pleural diseases based on the pleural LDH to ADA ratio and carcinoembryonic antigen (CEA). A pleural LDH to ADA ratio greater than 15.5 and a pleural CEA level of less than 5 ng/mL is indicative of PPE or empyema rather than TBPE, MPE, or transudative pleural effusion (CRF, CHF).This method has a sensitivity of 62.0%, a specificity of 91.0%, and an area under the receiver operating characteristic curve of 0.765 (95% confidence interval [CI]: 0678-0.852, P < .001), odds ratio of 16.6 (95% CI: 7.28-37.8, P < .001), a positive likelihood ratio (LR) of 6.8, and a negative LR of 0.02.

Routine monitoring with pleural manometry during therapeutic large-volume thoracentesis to prevent pleural-pressure-related complications: a multicentre, single-blind randomised controlled trial.

BACKGROUND: In patients with non-expandable lung, removal of pleural fluid can result in excessively negative pleural pressure, which is associated with chest discomfort, pneumothorax, and re-expansion pulmonary oedema. Pleural manometry is widely used to safeguard against pressure-related complications during thoracentesis despite little evidence to support the approach. We investigated whether monitoring of pleural pressure with manometry during thoracentesis could protect against complications compared with assessment of symptoms alone. METHODS: We did a prospective randomised single-blind trial involving patients with large pleural effusions at two academic medical centres in, Nashville, TN, and Baltimore, MD, USA. Eligible patients were adults with free-flowing effusions estimated to be at least 0·5 L who could remain seated throughout the procedure. Patients were randomly assigned 1:1 to receive thoracentesis guided by symptoms only (control) or by symptoms plus manometry at timepoints based on volume drained. The randomisation schedule was computer generated, used permuted blocks of four and six, and was stratified by participating institution. Patients, who were masked to study-group assignment, were asked to rate chest discomfort on 100 mm visual analogue scales before, during, and after drainage. In both groups drainage was discontinued before complete evacuation of pleural fluid if patients developed persistent chest discomfort, intractable cough, or other complications. In the manometry group, an additional criterion for stopping was if end-expiratory pleural pressure was lower than -20 cm H2O or declined by more than 10 cm H2O between two measurements to a value less than or equal to -10 cm H2O. The primary outcome was overall chest discomfort from before the start to after the procedure measured by patients 5 min after the end of drainage. Analysis was by modified intention to treat (ie, included all patients with any procedure or outcome data). This trial is registered with ClinicalTrials.gov, number NCT02677883. FINDINGS: Between March 4, 2016, and Sept 8, 2017, 191 patients were screened, of whom 128 were randomly assigned treatment and 124 were included in the final analysis (62 in each group). Four patients were excluded because of manometer malfunction (n=2), inability to access effusion due to pleural tumour burden (n=1), and inability to remain seated (n=1). Groups did not differ for the primary outcome (mean difference in chest discomfort score 2·4 mm, 95% CI -5·7 to 10·5, p=0·56). Six (10%) of 62 patients in the control group had asymptomatic pneumothorax ex vacuo compared with none in the manometry group (p=0·01). No serious complications occurred in either group. INTERPRETATION: Measurement of pleural pressure by manometry during large-volume thoracentesis does not alter procedure-related chest discomfort. Our findings do not support the routine use of this approach. FUNDING: Centurion Medical Products.

Amelanotic Malignant Melanoma with Dense Pleural Thickening Mimicking Malignant Mesothelioma.

A 51-year-old man was diagnosed with stage IIC nodular malignant melanoma (T4bN0M0) of the right upper arm. The tumor was treatment-refractory, and left-sided pleural effusion emerged 1.5 years later. Aspiration of pleural fluid revealed abundant amelanotic, atypical cells that resembled epithelial malignant mesothelioma or lung adenocarcinoma cells; these cells were positive for melanoma-associated antigen recognized by T cells (MART-1)/Melan-A, HMB-45, and S-100 on immunocytochemistry. Thoracic computed tomography (CT) revealed marked diffuse pleural thickening in the left hemithorax that mimicked malignant mesothelioma; thus, the present report describes the unique cytological and radiological findings of this case.

Diagnostic clue for pleural metastasis of malignant melanoma.

This case demonstrated the importance of recognition of melanin pigments in pleural effusion as a diagnostic tool for metastasis of malignant melanoma.

Management of parapneumonic effusion in pregnant women.

Pneumonia and parapneumonic effusion (PPE) are not more common in pregnant women compared to normal population. Pneumonia is considered the second most common infection in pregnant women. PPE is a serious complication of pneumonia and occurs especially in case of treatment delay or inappropriate antibiotic selection. The data on the management of PPE in pregnant women is limited to few case reports.

Cancer ratio and other new parameters for differentiation between malignant and nonmalignant pleural effusions.

Introduction In contrast to tuberculous pleurisy (TP), no accurate and commonly accepted biochemical marker of malignant pleural effusion (MPE) has been established. Objectives We aimed to evaluate the ability of a previously reported cancer ratio (CR) to discriminate between MPEs and non-MPEs; to test whether age may have additional value in differentiating MPEs from non-MPEs; and if so, to combine lactate dehydrogenase (LDH) and age with other TP biomarkers in search of an index useful in the identification of MPEs. Patients and methods A retrospective analysis of data from 140 patients with malignant (n = 74), tuberculous (n = 37), and parapneumonic (n = 29) pleural effusions was performed. The diagnostic performance of a test to discriminate between MPEs and non-MPEs was evaluated using the receiver operating characteristic curve analysis. Results Three ratios showed the largest area under the curve (AUC): serum LDH to pleural fluid soluble Fas ligand, age to pleural fluid adenosine deaminase (ADA), and serum LDH to pleural fluid interleukin 18; moreover, the ratios were characterized by high sensitivity (95%, 93.2%, and 92.9%, respectively) and fair specificity (64.8%, 71.2%, and 58.5%, respectively) for differentiating MPEs from non-MPEs. The AUC for CR was lower and showed a sensitivity of 94.6% and a specificity of 68.2%. Conclusions Our study showed a lower specificity of the CR for discriminating between MPEs and non-MPEs than previously reported. We demonstrated that the combinations of serum LDH with other pleural fluid biomarkers of TP have a similar diagnostic performance. We also found that age might be an important factor differentiating between MPEs and non-MPEs and proposed a new age to pleural fluid ADA ratio which has a discriminative potential similar to that of the CR.

An Observational Study Evaluating the Performance of LENT Score in the Selected Population of Malignant Pleural Effusion from Lung Adenocarcinoma in Singapore.

BACKGROUND: Patients with malignant pleural effusion (MPE) secondary to lung cancer have been associated with poor prognosis historically. LENT score developed to risk-stratify unselected patients with MPE predicts prognosis of < 6 months in patients with lung cancer. OBJECTIVE: To assess the performance of LENT score in predicting prognosis in selected population of MPE secondary to lung adenocarcinoma alone. METHODS: A retrospective observational study was conducted by reviewing the medical records of patients managed for MPE in the year 2012. RESULTS: Seventy patients with lung adenocarcinoma presenting with MPE were studied. The median (range) LENT score at initial diagnosis was 5 (2-7), and the median survival 7.9 (0.13-40) months. Thirty-nine patients received epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKIs). The median LENT score and median survival was 4 (2-7) and 14.4 months, respectively, in this group. Those in high-risk category by LENT in this group (n = 19) had a median survival and 6-month survival of 17.4 months and 73.6%, respectively. Thirty-one patients were treated with conventional chemotherapy. The median LENT score and median survival was 5 (2-7) and 4.1 (0.13-34.3) months, respectively, in this group. The median survival and 6-month survival rate in patients in high-risk category and moderate-risk category by LENT score was 6.2 months and 52.7%, and 11.4 months and 70.5%, respectively. CONCLUSION: LENT score underestimates prognosis in patients having MPE secondary to lung adenocarcinoma. This disparity particularly applies to the lung adenocarcinoma patients carrying EGFR mutation. Hence, LENT score may not be applicable to, or may need modification before applying to such patients.

Pleural manometry-historical background, rationale for use and methods of measurement.

Subatmospheric pleural pressure (Ppl), which is approximately -3 to -5 cmH2O at functional residual capacity (FRC) makes pleura a unique organ in the human body. The negative Ppl is critical for maintaining the lungs in a properly inflated state and for proper blood circulation within the thorax. Significant and sudden pleural pressure changes associated with major pleural pathologies, as well as therapeutic interventions may be associated with life-threatening complications. The pleural pressure may show two different values depending on the measurement method applied. These are called pleural liquid pressure and pleural surface pressure. It should also be realized that there are significant differences in pleural pressure distribution in pneumothorax and pleural effusion. In pneumothorax, the pressure is the same throughout the pleural space, while in pleural effusion there is a vertical gradient of approximately 1 cm H2O/cm in the pleural pressure associated with the hydrostatic pressure of the fluid column. Currently, two main methods of pleural pressure measurement are used: simple water manometers and electronic systems. The water manometers are conceptually simple, cheap and user-friendly but they only allow the estimation of the mean values of pleural pressure. The electronic systems for pleural pressure measurement are based on pressure transducers. Their major advantages include precise measurements of instantaneous pleural pressure and the ability to display and to store a large amount of data. The paper presents principles and details of pleural pressure measurement as well as the rationale for its use.

Pleural manometry in patients with pleural diseases - the usefulness in clinical practice.

Although pleural manometry is a relatively simple medical procedure it is only occasionally used to follow pleural pressure (Ppl) changes during a therapeutic thoracentesis and pneumothorax drainage. As some studies showed that pleural pressure monitoring might be associated with significant advantages, pleural manometry has been increasingly evaluated in the last decade. The major clinical applications of pleural pressure measurements include: the prevention of complications associated with large volume thoracentesis, diagnosis and differentiation between various types of an unexpandable lung and a possible prediction of the efficacy of chest tube drainage in patients with spontaneous pneumothorax. It is well known that the therapeutic thoracentesis might be complicated by cough, chest discomfort, and rarely, by a life threatening condition called reexpansion pulmonary edema (RPE). The serious adverse events of thoracentesis are related to pleural pressure drop rather than to the volume of removed pleural effusion. The use of pleural manometry during pleural fluid withdrawal enables the evaluation of the relationship between withdrawn pleural fluid volume, pleural pressure changes and procedure related complications. Pleural pressure measurement is also an important tool to study the different mechanism of pneumothorax complicating the thoracentesis. Pleural manometry is critical for measurement of pleural elastance, diagnosis of an unexpandable lung and differentiation between trapped lung and lung entrapment. This usually has significant clinical implications in terms of further management of patients with pleural effusion. The paper is a comprehensive review presenting different aspects of pleural pressure measurement in clinical practice.

Development and validation of a scoring system for the identification of pleural exudates of cardiac origin.

BACKGROUND: Light's criteria misclassify about 30% of cardiac effusions as exudates, possibly leading to unnecessary testing. Our purpose was to derive and validate a scoring model to effectively identify these falsely categorized cardiac effusions, in the setting of natriuretic peptide lacking data. METHODS: We retrospectively analyzed data from 3182 patients with exudative pleural effusions based on Light's criteria, of whom 276 had heart failure (derivation set). A scoring model was generated with those variables identified as independent predictors of cardiac effusions in a logistic regression analysis, and further evaluated in an independent population of 1165 patients. RESULTS: The score consisted of age ≥75years (3 points), albumin gradient >1.2g/dL (3 points), pleural fluid lactate dehydrogenase <250U/L (2 points), bilateral effusions on chest radiograph (2 points), and protein gradient >2.5g/dL (1 point). At the best cutoff of ≥7 points, the score yielded 92% diagnostic accuracy, a likelihood ratio positive of 12.7 and a likelihood ratio negative of 0.39 for labeling cardiac effusions in the derivation sample. The respective figures in the validation sample were 87%, 6.5 and 0.33. Notably, the score had higher discriminatory properties than protein and albumin gradients in both the derivation (respective area under the curve - AUC - of 0.925, 0.825, and 0.801) and validation (respective AUC of 0.908 0.862 and 0.802; all p≤0.01) cohorts. CONCLUSIONS: A simple scoring system can assist clinicians in accurately identifying false cardiac exudates when natriuretic peptides are not available.

Diagnostic approach to pleural diseases: new tricks for an old trade.

The burden of pleural diseases has substantially increased in the past decade because of a rise in the incidence of pleural space infections and pleural malignancies in a patient population that is older and more immunocompromised and has more comorbidities. This complexity increasingly requires minimally invasive diagnostic options and tailored management. Implications for patients are such that the limitations of current diagnostic methods need to be addressed by multidisciplinary teams of investigators from the fields of imaging, biology, and engineering. Ignored for a long time as an epiphenomenon at the crossroad of many unrelated medical problems, pleural diseases are finally getting the attention they deserve and have spurred a vibrant and exciting field of research.

Computed tomography scoring system for discriminating between parapneumonic effusions eventually drained and those cured only with antibiotics.

BACKGROUND AND OBJECTIVE: Due to limited data, we aimed to develop and validate a computed tomography (CT)-based scoring system for identifying those parapneumonic effusions (PPEs) requiring drainage. METHODS: A retrospective review of all patients with PPE who underwent thoracentesis and a chest CT scan before any attempt to place a tube thoracostomy, if applicable, over an 8-year period was conducted. Eleven chest CT characteristics were compared between 90 patients with complicated PPEs (CPPEs), defined as those which eventually required chest drainage, and 60 with non-complicated effusions (derivation sample). A scoring system was devised with those CT findings identified as independent predictors of CPPE in a logistic regression analysis, and further validated in an independent population of 59 PPE patients. RESULTS: CT scores predicting CPPE were pleural contrast enhancement (3 points), pleural microbubbles, increased extrapleural fat attenuation and fluid volume ≥400 mL (1 point each). A sum score of ≥4 yielded 84% sensitivity (95% CI: 62-85%), 75% specificity (95% CI: 62-85%), 81% diagnostic accuracy (95% CI: 73-86%), likelihood ratio (LR) positive of 3.4 (95% CI: 2.1-5.4), LR negative of 0.22 (95% CI: 0.13-0.36) and area under the receiver operating characteristic curve (AUC) of 0.829 (95% CI: 0.754-0.904) for labelling CPPE in the derivation set. These results were reproduced in the validation sample. The CT grading scale also exhibited a fair ability to identify patients who needed surgery or would die from the pleural infection (AUC: 0.76, 95% CI: 0.61-0.9). CONCLUSION: A novel CT scoring system for adults with PPE may allow clinicians to predict the need for chest tube drainage with good accuracy.

Randomized Trial of Pleural Fluid Drainage Frequency in Patients with Malignant Pleural Effusions. The ASAP Trial.

RATIONALE: Patients with malignant pleural effusions have significant dyspnea and shortened life expectancy. Indwelling pleural catheters allow patients to drain pleural fluid at home and can lead to autopleurodesis. The optimal drainage frequency to achieve autopleurodesis and freedom from catheter has not been determined. OBJECTIVES: To determine whether an aggressive daily drainage strategy is superior to the current standard every other day drainage of pleural fluid in achieving autopleurodesis. METHODS: Patients were randomized to either an aggressive drainage (daily drainage; n = 73) or standard drainage (every other day drainage; n = 76) of pleural fluid via a tunneled pleural catheter. MEASUREMENTS AND MAIN RESULTS: The primary outcome was the incidence of autopleurodesis following the placement of the indwelling pleural catheters. The rate of autopleurodesis, defined as complete or partial response based on symptomatic and radiographic changes, was greater in the aggressive drainage arm than the standard drainage arm (47% vs. 24%, respectively; P = 0.003). Median time to autopleurodesis was shorter in the aggressive arm (54 d; 95% confidence interval, 34-83) as compared with the standard arm (90 d; 95% confidence interval, 70 to nonestimable). Rate of adverse events, quality of life, and patient satisfaction were not significantly different between the two arms. CONCLUSIONS: Among patients with malignant pleural effusion, daily drainage of pleural fluid via an indwelling pleural catheter led to a higher rate of autopleurodesis and faster time to liberty from catheter. Clinical trial registered with www.clinicaltrials.gov (NCT 00978939).

A new diagnostic approach for bilious pleural effusion.

BACKGROUND: Bilious pleural effusion is an extremely rare condition associated with liver diseases, subphrenic or subhepatic abscess formation, biliary peritonitis, and invasive procedures (i.e., percutaneous biliary drainage or liver biopsy). The current diagnostic test is based on the measurement of the ratio of pleural total bilirubin to serum total bilirubin, which is greater than 1 in patients with bilious pleural effusion. Given the low incidence of bilious pleural effusion, the precise diagnostic yield of this ratio based test has not been evaluated. METHODS: We retrospectively reviewed the medical records of our institution and searched the PubMed database for reports of bilious pleural effusion. RESULTS: We identified a total of 12 cases of bilious pleural effusion (9 from 8 Pubmed reports and 3 from our institutional records). The factors causing this condition were broadly classified into three categories based on the pathophysiology: 1) liver diseases (echinococcosis, tuberculosis and amebiasis); 2) subhepatic/subphrenic abscess or biliary peritonitis, with or without biliary tract obstruction; and 3) iatrogenic disease after percutaneous biliary drainage and/or liver biopsy. The sensitivity of detection was 76.9% when the ratio of pleural total bilirubin to serum total bilirubin was greater than 1. The sensitivity increased to 100% when a combination test including pleural glycoholic acid was adopted. CONCLUSIONS: This study demonstrates the high diagnostic yield for bilious pleural effusion using a combination of two test criteria; a ratio of pleural total bilirubin to serum total bilirubin greater than 1 and the presence of pleural glycoholic acid.