Pleural effusions are common in clinical practice. In general, the diagnostic approach starts with thoracentesis. Serous (yellow) and blood tinged (reddish) pleural effusions are the most common types of pleural fluid at thoracentesis. Black colored pleural effusions are an extremely rare entity and knowledge regarding this entity is limited to case reports. A thorough systemic search on PubMed database was done looking at all reported cases of black pleural effusion. Broadly, dividing black pleural effusion based on etiology, the causes are as follows: (1) infectious – especially fungal – Aspergillus niger, Rhizopus oryzae, (2) malignancy ‑ metastatic melanoma and primary lung cancers, (3) pancreaticopleural fistula, and (4) miscellaneous causes‑ including crack cocaine use, rheumatoid pleurisy, and charcoal containing empyema. Treatment of these effusions involves treatment of the underlying cause. Black pleural effusions are very rare entities with a limited differential, which the treating clinician should consider when encountered in clinical practice.

Multiple myeloma (MM) is a common hematologic malignancy. Pleural effusion is a rare presenting feature of multiple myeloma which carries a poor prognosis. Few cases of multiple myeloma with pleural involvement have been reported in the medical literature. We report a patient with MM diagnosed by cytologic examination of pleural fluid. Our patient was a 64- year old man with multiple myeloma who was receiving chemotherapy. He had developed dry coughs and exertional dyspnea about a month prior to the admission. Radiographic examination showed left pleural effusion with mediastinal shift to the opposite side. Diagnostic thoracentesis of pleural fluid was performed for the patient. Pathologic examination of pleural fluid showed plasmocytes and plasmablast type mononuclear cells with atypical nuclei, consistent with the diagnosis of pleural effusion due to multiple myeloma. In view of multiple etiologies of pleural effusion in malignant diseases, rare etiologies should also be considered in order to treat the effusion appropriately.

Background: The differential diagnosis of tuberculous pleural effusion (TPE) and malignant pleural effusion (MPE) is difficult because the biochemical profiles are similar. The present study aimed to differentiate TPE from MPE, using a decision tree and a weighted sparse representation-based classification (WSRC) method, based on the best combination of routine pleural effusion fluid biomarkers. Materials and Methods: The routine biomarkers of pleural fluid, including differential cell count, lactate dehydrogenase (LDH), protein, glucose and adenosine deaminase (ADA), were measured in 236 patients (100 with TPE and 136 with MPE). A Sequential Forward Selection (SFS) algorithm was employed to obtain the best combination of parameters for the classification of pleural effusions. Moreover, WSRC was compared to the standard sparse representation-based classification (SRC) and the Support Vector Machine (SVM) methods for classification accuracy. Results: ADA provided the highest diagnostic performance in differentiating TPE from MPE, with 91. 91% sensitivity and 74. 0% specificity. The best combination of parameters for discriminating TPE from MPE included age, ADA, polynuclear leukocytes and lymphocytes. WSRC outperformed the SRC and SVM methods, with an area under the curve of 0. 877, sensitivity of 93. 38%, and specificity of 82. 0%. The generated flowchart of the decision tree demonstrated 87. 2% accuracy for discriminating TPE from MPE. Conclusion: This study indicates that a decision tree and a WSRC are novel, noninvasive, and inexpensive methods, which can be useful in discriminating between TPE and MPE, based on the combination of routine pleural fluid biomarkers.

Background and Aim: Pleural effusion is the second most common type of extra pulmonary tuberculosis with an incidence of 4.9%. This study aims to describe the age distribution, main clinical, laboratory and radiographic findings and outcome of patients with Tuberculous Pleural Effusion (TPE).Materials and Methods: This is a retrospective study of TPE patients admitted in pediatric ward of Masih Daneshvari Hospital from 2002 to 2008. Eighteen patients under 18 years of age were included in our study. Results: The patients in our study were 12 boys (66.7%) and 6 girls (33.3%) who were all in the 10-18 age bracket. The most common presenting symptoms and signs were cough (17 patients, 94.4), anorexia (14 patients, 77.8%), fever (13 patients, 72.2%), chest pain (10patients, 55.6%), tachypnea and respiratory distress (2 patients, 11%), cyanosis (1 patient 5.5%). All subjects showed exudative pleural fluid with lymphocytosis >50%. Acid fast bacilli (AFB) were not detected in the sputum, gastric and/or pleural fluid of any of the patients. Sputum culture was positive in 4 (23.5%). Positive pleural culture was not seen in any of the patients. Pleural biopsies were available in 88% of which showed necrotizing granulomatous inflammation. The most common radiographic findings were unilateral PE (100%), mediastinal lymphadenopathy (22%) and consolidation (11.1%). Eighteen patients received medical treatment.Conclusion: The clinical manifestation of childhood TPE is not specific and especially in countries with high prevalence of TB it should always be considered in the differential diagnosis for older children suffering from parapneumonic effusion.

Background: Primary and secondary infections and malignancies are inflammatory causes of fluid accumulation in the pleural space. TB is one of the infective causes of pleural effusion and is similar to malignancies because of its subacute and chronic process; although their management is extremely different. CA-125 is a glycoprotein tumor marker with molecular weight of 200 KD, which is found on the surface of ovarian and some normal and inflammatory cells. In both malignancy and tuberculosis, this tumor marker increases in serum and consequently in pleural fluid. This study was conducted to evaluate and compare CA-125 tumor marker in pleural effusion resulting from malignancies and tuberculosis. Materials and Methods: twenty-seven TB patients (18 men and 9 women), with the mean (±SD)age of 37.3±13.9 yrs. And 23 patients affected by malignant tumors (16 men and 7 women) with the mean (±SD) age of 57.9±17. 7 yrs. were evaluated during 2004-2005. In malignant cases, diagnosis was made through microscopic inspection of the biopsy samples and cytology of pleural fluid. For recognition of tuberculosis, culture and smear of sputum or gastric lavage, biopsy of pleura and pleural fluid and PCR methods were used. Pleural fluid samples were collected and the amount of their CA-125 was measured by CLIA method. The cut-off value of CA-125 was obtained from a ROC curve. Results: The mean (±SD) level of CA-125 in pleural fluid was 159.1±214, and 2149.2±4513.6 U/ml in tuberculosis and malignancies, respectively; which showed a statistically significant difference between the two groups (p<0.01). Conclusion: CA-125 marker levels in pleural effusion may be used as a diagnostic index for differentiation of TB and malignancy induced pleural effusions.      

Background: Pulmonary complications after cardiac surgery are a major source of morbidity and mortality, as well as increased lengths of hospital stay and resource utilization. Pleural effusion following coronary artery bypass graft surgery (CABG) has been reported in 65% to 89% of cases. The present study was designed to determine the prevalence of pleural effusion after open-heart surgery. Methods: This study evaluated 600 patients who underwent open-heart surgery. The study population was divided into 3 groups: group A consisted of 200 patients who underwent CABG, group B comprised 200 patients who underwent aortic valve replacement (AVR) and mitral valve replacement (MVR), and group C encompassed 200 patients who underwent valve surgery and CABG. Chest radiography was performed before surgery and afterward on the first, third, and seventh postoperative days. Results: The study population was comprised of 330 (55%) men and 270 (45%) women. The size of the pleural effusion was small in a large proportion of the patients (45%, n = 270). Additionally, 90 (15%) patients had moderate effusion, occupying between 20% and 40% of the hemithorax, and 84 (14%) patients had large effusion. Conclusions: Pleural effusion was detected in 37% of the patients after CABG, 25% after valve surgery (MVR+AVR), and 20% after CABG and valve surgery. Most of the cases of effusion after cardiac surgery were left-sided.