A decision tree for differentiating tuberculous from malignant pleural effusions.

OBJECTIVE: To improve physicians' ability to discriminate tuberculous from malignant pleural effusions through a simple clinical algorithm that avoids pleural biopsy. DESIGN: We retrospectively compared the clinical and pleural fluid features of 238 adults with pleural effusion who satisfied diagnostic criteria for tuberculosis (n=64) or malignancy (n=174) at one academic center (derivation cohort). Then, we built a decision tree model to predict tuberculosis using the C4.5 algorithm. The model was validated with an independent sample set from another center that included 74 tuberculous and 293 malignant effusions (validation cohort). RESULTS: Among 12 potential predictor variables, the classification tree analysis selected four discriminant parameters (age>35 years, pleural fluid adenosine deaminase>38U/L, temperature>or=37.8 degrees C, and pleural fluid LDH>320U/L) from the derivation cohort. The generated flowchart had 92.2% sensitivity, 98.3% specificity, and an area under the ROC curve of 0.976 for diagnosing tuberculosis. The corresponding operating characteristics for the validation cohort were 85.1%, 96.9% and 0.958. CONCLUSIONS: Applying a decision tree analysis that contains simple clinical and laboratory data can help in the differential diagnosis of tuberculous and malignant pleural effusions.

Assessment of endoglin and calprotectin as potential biomarkers in ovarian carcinoma and borderline tumors of the ovary.

OBJECTIVE: The objective of the study was to analyze circulating endoglin concentration in ovarian carcinoma and evaluate a prognostic role for calprotectin and endoglin in effusions in advanced-stage disease. STUDY DESIGN: Preoperative plasma concentration of endoglin from women with benign ovarian tumors (n = 71), borderline ovarian tumors (BOT, n = 39), and ovarian carcinomas (n = 89) was analyzed with an enzyme-linked immunosorbent assay, as were endoglin and calprotectin concentrations in effusions from 164 women with advanced-stage ovarian carcinoma. RESULTS: Median endoglin plasma concentration was higher in the BOT group as compared with both control and invasive carcinoma groups (4.9 vs 4.5 and 4.3 ng/mL, P = .04 and P = .02), whereas the difference between the control and invasive group was not statistically significant (4.5 vs 4.3 ng/mL, P = .08). Endoglin and calprotectin effusion concentrations did not correlate with survival. CONCLUSION: Circulating endoglin is not elevated in advanced ovarian carcinoma. This is in contrast to the situation in breast and gastric cancer.

Pleural fluid interferon-gamma and adenosine deaminase levels in tuberculosis pleural effusion: a cost-effectiveness analysis.

Pleural fluid levels of interferon-gamma (IFN-gamma) and adenosine deaminase (ADA) have been found to be high in patients with tuberculosis (TB). The present study was carried out to compare the diagnostic utility of these two markers and to carry out a cost-effectiveness analysis of performing IFN-gamma estimation in comparison to ADA. A total of 52 patients with pleural effusion, 35 of which were found to have TB etiology, were prospectively included for estimation of ADA and IFN-gamma levels. The difference in the cost of performing the two diagnostic tests was compared with the cost of the treatment for a patient with TB. Pleural fluid IFN-gamma (median [range]: 2,100 [70-14,000] vs. 3 [0-160]; P<0.001) as well as ADA levels (mean [SD]: 93.1 [62.3] vs 15.4 [8.7]; P<0.001) were significantly higher in patients with TB effusion. Even though IFN-gamma estimation was more sensitive (97.1 vs. 91.4%), the extra cost of IFN-gamma estimation for detecting one patient with TB was found to be equivalent to the cost of a complete course of antituberculosis treatment for six patients. In developing countries, where TB is rampant and cost is a major concern, pleural fluid IFN-gamma estimation does not seem to be a cost-effective investigation method for differentiating TB from non-TB pleural effusion.

Tumour necrosis factor alpha in the diagnostic assessment of pleural effusion.

We investigated the role of tumour necrosis factor-alpha (TNF) in the evaluation of pleural effusion aetiology. Using a commercially-available ELISA kit, concentrations of TNF were measured in the serum and pleural fluid of patients with malignant effusions (n=19), uncomplicated parapneumonic effusions (n=13), and exudative (n=13) and transudative (n=13) effusions due to congestive heart failure (CHFex and CHFtr, respectively). Serum TNF did not differ significantly between the four groups (p>0.05). In the group with malignancy, pleural fluid TNF was significantly higher than in the other groups (p<0.001), which were not significant different from each other (p>0.05). However, a considerable overlap between all four groups was found. Pleural fluid TNF was significantly higher than serum TNF in the malignant and the uncomplicated parapneumonic groups (p<0.001), and there was a significant positive correlation between serum TNF and pleural fluid TNF in the group with uncomplicated parapneumonic effusion (r=0.7, p<0.005), in the group with CHFex (r=0.54, p<0.01), and in the group with CHFtr (r=0. 8, p<0.005), but not in the group with malignancy. Pleural fluid TNF:serum TNF (TNF ratio) was significantly higher in the malignancy group than in the other groups (p<0.001); no significant difference was found between the other three groups (p>0.05). At an optimal cut-off point of 2.0 for TNF ratio, determined by ROC analysis for discrimination between malignant and non-malignant groups, sensitivity was 84%, specificity 90%, and total accuracy 88% (p<0. 0001). TNF ratio might be helpful in the diagnostic assessment of exudative pleural effusion.

A comparative analysis of the biochemical parameters used to distinguish between pleural exudates and transudates.

OBJECTIVE: The aim of the present study was to compare the various parameters used to identify exudates. METHODOLOGY: The study included 255 patients with pleural effusions. According to aetiological diagnosis, 105 pleural effusions were labelled as transudates and 150 were labelled as exudates. RESULTS: Using the criteria of Light et al., 94.5% of the effusions were correctly classified, yielding a sensitivity and specificity of 99.3% and 87.6%, respectively. Use of the pleural fluid/serum bilirubin ratio produced results of 92.9%, 90.7%, and 96.2%, respectively. Using pleural fluid cholesterol level yielded results of 95.7%, 95.3%, and 96.2%, respectively. When the combination of pleural fluid cholesterol level and lactate dehydrogenase (LDH) level was used, the specificity and accuracy were found to be higher than that using the criteria of Light et al. We found that there was no significant difference among the parameters with respect to accuracy. CONCLUSION: When the accuracy and cost are considered, differentiation of pleural exudates and transudates can be achieved only by pleural fluid cholesterol level or LDH level; and when two parameters were used together, the accuracy and specificity were higher than that using the criteria of Light et al.

Indwelling small pleural catheter needle thoracentesis in the management of large pleural effusions.

STUDY OBJECTIVES: To evaluate the clinical safety, efficacy, and cost of a small indwelling pleural catheter (7F, Turkel Safety Thoracentesis System [Sherwood, Davis, and Geck; St. Louis]) vs repeated needle thoracentesis or closed tube thoracostomy as a means to drain a large-volume pleural effusion. SETTING: Inpatients in a tertiary care university teaching hospital in urban Chicago. DESIGN: Prospective, consecutive patient comparative study using historical controls. PATIENTS: Fifty-seven therapeutic aspirations in 23 patients with large pleural effusions as defined by opacification of at least one third of the hemithorax on chest radiography. Patients were excluded if they had a history of thoracic surgery, documented loculations, structural chest abnormalities, severe coagulopathy, or refused to give informed consent. MEASUREMENTS: Volume of each pleural aspiration, total fluid removed, pleural fluid lactate dehydrogenase, protein, glucose, cytologic analysis, microbiologic stains, and cultures based on clinical indications. RESULTS: We found that initial thoracentesis and repeated pleural drainage using the indwelling catheter system is a safe, efficacious, and cost-effective procedure that may aid the evacuation and management of a large-volume pleural effusion. There were fewer adverse effects and complications such as pneumothorax, splenic laceration, hemopneumothorax, local pain, dry tap, and hematomas, as compared with previous reports. The overall complication rate was 12% (7/57). There were two pneumothoraces detected (3.5%), one of which required closed tube thoracostomy for treatment (1.75%). A further benefit comes in the form of a significant cost savings at our institution ($80 vs $240) when this needle-catheter system is used in place of closed tube thoracostomy in the drainage of a large-volume pleural effusion. CONCLUSION: An indwelling pleural catheter with the Turkel safety needle-catheter (as described in the study) can be used to successfully drain the pleural space with reduced morbidity and a significant cost saving in comparison to repeated needle thoracenteses or closed tube thoracostomy.

Pleural fluid chemical analysis in parapneumonic effusions. A meta-analysis.

Controversy exists regarding the clinical utility of pleural fluid pH, lactate dehydrogenase (LDH), and glucose for identifying complicated parapneumonic effusions that require drainage. In this report, we performed a meta-analysis of pertinent studies, using receiver operating characteristic (ROC) techniques, to assess the diagnostic accuracy of these tests, to determine appropriate decision thresholds, and to evaluate the quality of the primary studies. Seven primary studies reporting values for pleural fluid pH (n = 251), LDH (n = 114), or glucose (n = 135) in pneumonia patients were identified. We found that pleural fluid pH had the highest diagnostic accuracy for all patients with parapneumonic effusions as measured by the area under the ROC curve (AUC = 0.92) compared with pleural fluid glucose (AUC = 0.84) or LDH (AUC = 0.82). After excluding patients with purulent effusions, pH (AUC = 0.89) retained the highest diagnostic accuracy. Pleural fluid pH decision thresholds varied between 7.21 and 7.29 depending on cost-prevalence considerations. The quality of the primary studies was the major limitation in determining the value of pleural fluid chemical analysis. We conclude that meta-analysis of the available data refines the application of pleural fluid chemical analysis but a clearer understanding of the usefulness of these tests awaits more rigorous primary investigations.

Intrapleural fibrinolytic treatment of multiloculated thoracic empyemas.

Acute multiloculated thoracic empyemas incompletely drained by tube thoracostomy alone usually require operation. To avoid a thoracotomy yet treat this difficult problem, intrapleural fibrinolytic agents were employed. Between April 1, 1990, and April 1, 1993, 13 consecutive patients presenting with a fibrinopurulent empyema were demonstrated to have incomplete drainage. To facilitate drainage, streptokinase, 250,000 units in 100 mL 0.9% saline solution (3 patients), or urokinase, 100,000 units in 100 mL 0.9% saline solution (10 patients), was instilled daily into the chest tube, and the tube was clamped for 6 to 12 hours followed by suction. This routine was continued daily for a mean of 6.8 +/- 3.7 days (range, 1 to 14 days) until resolution of the pleural fluid collection was demonstrated by computed chest tomography and clinical indications. This regimen was completely successful in 10 of 13 patients (77%), who had resolution of the empyema, eventual withdrawal of chest tubes, and no recurrence. Two patients, both pediatric liver transplant patients, had an initial good response but eventually required decortication. One patient with a good radiographic response became increasingly febrile during streptokinase therapy and underwent a thoracotomy, but no significant undrained fluid was found. This patient's continued fever was believed to be a streptokinase reaction. Urokinase was used subsequently. No treatment-related mortalities or complications occurred. Intrapleural fibrinolytic agents, especially urokinase, are safe, cost-effective means of facilitating complete chest tube drainage, thereby avoiding the morbidity of a major thoracotomy for 77% of a group of multiloculated empyema patients who traditionally would have required open surgical therapy.