Causes of pleural exudates in a region with a high incidence of tuberculosis

Myeloid-derived suppressor cells in pleural effusion as a diagnostic marker for early discrimination of pulmonary tuberculosis from pneumonia

Introduction

Tuberculous pleural effusion (TPE) stands as one of the primary forms of extrapulmonary tuberculosis (TB) and frequently manifests in regions with a high prevalence of TB, consequently being a notable cause of pleural effusion in such areas. However, the differentiation between TPE and parapneumonic pleural effusion (PPE) presents diagnostic complexities. This study aimed to evaluate the potential of myeloid-derived suppressor cells (MDSCs) in the pleural fluid as a potential diagnostic marker for distinguishing between TPE and PPE.

Methods

Adult patients, aged 18 years or older, who presented to the emergency room of a tertiary referral hospital and received a first-time diagnosis of pleural effusion, were prospectively enrolled in the study. Various immune cell populations, including T cells, B cells, natural killer (NK) cells, and MDSCs, were analyzed in both pleural fluid and peripheral blood samples.

Results

In pleural fluid, the frequency of lymphocytes, including T, B, and NK cells, was notably higher in TPE compared to PPE. Conversely, the frequency of polymorphonuclear (PMN)-MDSCs was significantly higher in PPE. Notably, compared to traditional markers such as the neutrophil-to-lymphocyte ratio and adenosine deaminase level, the frequency of PMN-MDSCs emerged as a more effective discriminator between PPE and TPE. PMN-MDSCs demonstrated superior positive and negative predictive values and exhibited a higher area under the curve in the receiver operating characteristic curve analysis. PMN-MDSCs in pleural effusion increased the levels of reactive oxygen species and suppressed the production of interferon-gamma from T cells following nonspecific stimulation. These findings suggest that MDSC-mediated immune suppression may contribute to the pathology of both TPE and PPE.

Discussion

The frequency of PMN-MDSCs in pleural fluid is a clinically useful indicator for distinguishing between TPE and PPE.

A comparative study of diagnostic accuracy in 3026 pleural biopsies and matched pleural effusion cytology with clinical correlation

BACKGROUND

Pleural effusion can be caused by a wide range of benign and malignant conditions. Pleural biopsy and effusion cytology represent two key methods of pathological diagnosis. To compare the performance these two methods, a large cohort of matched pleural biopsy and effusion cytology with clinical follow-up was reviewed.

METHODS

Pleural biopsies and effusion cytology specimens over a period of 18 years were retrieved. Cytology specimens collected within 7 days of pleural biopsy were matched. Reports were reviewed, and the cause for pleural effusion was determined by hospital disease coding and clinical data.

RESULTS

Totally, 3026 cases were included. The leading cause of benign effusion was tuberculosis (n = 650). Malignant pleural effusion (MPE) was more common in older females (p < 0.001) and mostly due to lung cancer (n = 959), breast cancer (n = 64), and mesothelioma (n = 48). The inadequate/insufficient (B1/C1) rate of biopsy was higher than cytology (15.6% vs. 0.3%) but the rates for other diagnostic categories were similar. Biopsy and cytology showed a correlation coefficient of 0.315, improving to 0.449 when inadequate/insufficient (B1/C1) cases were excluded. The ROM for benign cytology (C2) was lower than biopsy (B2) (p < 0.001). Compared with biopsy, the diagnostic accuracy was higher in cytology overall and for metastatic carcinomas (p < 0.001) but lower for hematolymphoid malignancies (p = 0.014) and mesotheliomas (p = 0.002).

CONCLUSIONS

These results suggest that effusion cytology may be better for confirming benignity and diagnosing carcinomatous MPE. In these cases, pleural biopsy may be withheld to reduce procedural risks. However, for suspected hematolymphoid malignancies and mesothelioma, biopsy should be considered.

Diagnostic value of pleural cholesterol in differentiating exudative and transudative pleural effusion

Background

Pleural effusions are most commonly classified as transudative or exudative based on Light's criteria which has shown misclassification in 10%–20% of cases. Studies have demonstrated lesser misclassification with pleural fluid cholesterol criteria. Thus, this study aimed to find the diagnostic properties of pleural fluid cholesterol in differentiating the type of effusion.

Materials and methods

This cross-sectional study involving 72 patients was undertaken in a tertiary center in Nepal for a duration of 2 years. On the basis of Light's, Heffner's, etiological, and pleural fluid cholesterol criteria, pleural effusion was classified as exudative or transudative. The findings were then evaluated to determine the diagnostic value of each approach in identifying the effusion type and comparing them on the basis of sensitivity, specificity, positive predictive value and negative predictive value.

Result

Pleural fluid cholesterol detected effusion as exudative with sensitivity of 91.94% and specificity of 80.00% against Light's criteria; with a sensitivity of 98.28% and specificity of 85.71% against the etiological diagnosis. Additionally, against the etiological diagnosis, sensitivity of both Light's and Heffner's criteria was 100%; however, specificity was 71.43% and 64.29% respectively, which is far less than that of pleural fluid cholesterol (85.71%). Furthermore, pleural fluid cholesterol was also found to have better results than protein ratio, LDH ratio and pleural fluid protein ratio in determining the type of effusion.

Conclusion

When considering the avoidance of confusing outcomes in equivocal instances and cost effectiveness in developing nations, pleural fluid cholesterol can be one of the most useful alternative diagnostic methods for differentiating between exudative or transudative effusions.

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Tuberculosis is one of the most common observed causes of exudative pleural effusions.

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A patient with an effusion when classified according to different criteria can yield different results.

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The number of patients classified as exudative or transudative effusion varies according to different parameters used.

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Pleural cholesterol has better sensitivity, specificity, PPV and NPV in differentiating pleural effusion.

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Analysis of the pleural cholesterol can become one of the best diagnostic tools to differentiate the type of effusion.

The Clinical Experience of Mycobacterial Culture Yield of Pleural Tissue by Pleuroscopic Pleural Biopsy among Tuberculous Pleurisy Patients

Background and Objectives: Tuberculous pleurisy is a common extrapulmonary TB that poses a health threat. However, diagnosis of TB pleurisy is challenging because of the low positivity rate of pleural effusion mycobacterial culture and difficulty in retrieval of optimal pleural tissue. This study aimed to investigate the efficacy of mycobacterial culture from pleural tissue, obtained by forceps biopsy through medical pleuroscopy, in the diagnosis of TB pleurisy. Materials and Methods: This study retrospectively enrolled 68 TB pleurisy patients. Among them, 46 patients received semi-rigid pleuroscopy from April 2016 to March 2021 in a tertiary hospital. We analyzed the mycobacterial culture from pleural tissue obtained by forceps biopsy. Results: The average age of the study participants was 62.8 years, and 64.7% of them were men. In the pleuroscopic group, the sensitivity of positive Mycobacterium tuberculosis (M. TB) cultures for sputum, pleural effusion, and pleural tissue were 35.7% (15/42), 34.8% (16/46), and 78.3% (18/23), respectively. High sensitivities of M. TB culture from pleural tissue were up to 94.4% and 91.7% when pleural characteristic patterns showed adhesion lesions and both adhesion lesions and presence of micronodules, respectively. Conclusions: M. TB culture from pleural tissue should be considered a routine test when facing unknown pleural effusion during pleuroscopic examination.

Echographic septation: A potentially useful indicator discriminating tuberculous from malignant pleural effusion

BACKGROUND

Tuberculous (TBE) and malignant (MPE) pleural effusions present with similar lymphocytic exudates. As TBE is an inflammatory and hypersensitivity process, we hypothesized that echographic septation may be more prevalent in TBE than in MPE, potentially serving as a good clinical predictor for TBE.

METHODS

A total of 183 TBE and 266 MPE patients were recruited retrospectively. Multivariate logistic regression was performed to determine significant predictors for TBE.

RESULTS

TBE diagnosis was confirmed histologically (caseating granuloma) in 84.7% of the cases, while MPE was biopsy-proven in 63.9% of the cases. Echographic septation was more evident in TBE than in MPE (46.5% vs. 8.2%, p < 0.001). Multivariate logistic regression analysis showed that male sex, serum leucocyte count ≤9 × 10⁹/L or pleural fluid protein ≥50 g/L, and echographic septation (aOR: 9.28, p < 0.001) were independent predictors for TBE. These parameters collectively provided a diagnostic accuracy of 79.61% (95% CI 74.13-84.38).

CONCLUSIONS

Echographic septation may potentially facilitate discrimination between TBE and MPE as part of a clinical prediction model. Prospective validation of this prediction model in an external cohort is anticipated.

Rapid Detection of Mycobacterium tuberculosis in Pleural Fluid Using Resuscitation-Promoting Factor-Based Thin Layer Agar Culture Method

Background

Pleural tuberculous is difficult to diagnose. Culture is still considered the gold standard, especially in resource-limited settings where quick, cheap, and easy techniques are needed. The aim of the study was to evaluate resuscitation-promoting factors (Rpfs)-based thin layer agar (TLA) culture method for quick detection of Mycobacterium tuberculosis in pleural fluid.

Methods

Patients with suspected pleural TB were enrolled prospectively in our hospital, pleural fluid of all patients were collected, stained with Ziehl–Neelsen for acid-fast bacilli (AFB), cultured on Rpfs-TLA, TLA, and Löwenstein–Jensen (LJ) medium, and identified according to recommended procedures.

Results

A total of 137 suspected pleural TB were enrolled and categorized, including 103 pleural TB (49 confirmed and 54 probable pleural TB) and 34 non-TBP patients. The sensitivity of Rpfs-TLA for total pleural TB was 43.7% (34.5∼53.3%), higher than that of TLA 29.1% (21.2∼38.5%) and LJ 26.2% (18.7∼35.5%) (p < 0.01), and all specificity was 100% in the diagnosis of pleural TB. Median time to detection of a positive culture was 11.8 days (95% CI 10.4∼13.4) for Rpfs-TLA, 21.0 days (95% CI 19.1∼22.9) for TLA, and 30.5 days (95% CI 28.5∼32.5) for LJ (p < 0.001).

Conclusion

Rpfs-TLA is an accurate, rapid, cheap, and easy culture method, which makes it promising for use in clinical laboratories.

Tuberculous pleural effusion in a patient with sympathetic ophthalmia on immunosuppression: a case report

BACKGROUND

Tuberculous pleural effusion (TPE) is paucibacillary, making its diagnosis difficult based on laboratory investigations alone. We present a case of a patient with a TPE who was initially misdiagnosed to have azathioprine-induced lung injury. The diagnosis of TPE was arrived at with the help of clinical assessment, laboratory and radiological investigations.

CASE PRESENTATION

A 25-year-old chronic smoker with sympathetic ophthalmia on long-term immunosuppression, latent tuberculosis infection and a significant family history of tuberculosis presented with a three-week history of productive cough, low-grade fever, night sweats and weight loss. Examination of the lungs showed reduced breath sounds at the right lower zone. Chest x-ray showed minimal right pleural effusion with a small area of right upper lobe consolidation. The pleural fluid was exudative with predominant mononuclear leukocytes. Direct smears of sputum and pleural fluid; polymerase chain reaction of pleural fluid; and sputum, pleural fluid and blood cultures were negative for M. tuberculosis (MTB) and other organisms. As he did not respond to a course of broad-spectrum antibiotics, he was then treated as a case of azathioprine-induced lung injury. However, his condition did not improve despite the cessation of azathioprine. A contrast-enhanced computed tomography of the thorax showed right upper lobe consolidation with tree-in-bud changes, bilateral lung atelectasis, subpleural nodule, mild right pleural effusion and mediastinal lymphadenopathy. Bronchoalveolar lavage was negative for malignant cells and microorganisms including, MTB. However, no pleural biopsy was done. He was empirically treated with anti-tubercular therapy for 9 months duration and showed complete recovery.

CONCLUSION

A high index of suspicion for TPE is required in individuals with immunosuppression living in regions endemic to tuberculosis. Targeted investigations and sound clinical judgement allow early diagnosis and prompt treatment initiation to prevent morbidity and mortality.

Diagnosis of tuberculosis pleurisy with three endoscopic features via pleuroscopy

Background:

Tuberculosis (TB) is a constant threat even with a worldwide active public health campaign. Diagnosis of TB pleurisy is challenging in the case of pleural effusion of unknown origin after aspiration analysis. The study was designed to demonstrate a simple image interpretation technique to differentiate TB pleurisy from non-TB pleurisy using semi-rigid pleuroscopy.

Methods:

The study retrospectively enrolled 117 patients who underwent semi-rigid pleuroscopy from April 2016 to August 2018 in a tertiary hospital. We analyzed the possibility of TB pleurisy using three simple pleuroscopic images via semi-rigid pleuroscopy.

Results:

Among 117 patients, 28 patients (23.9%) were diagnosed with TB pleurisy. Sago-like nodules/micronodules, adhesion, and discrete distribution were noted in 20 (71.4%), 20 (71.4%), and 19 (67.9%) patients with TB pleurisy, respectively. Sago-like nodules/micronodules, adhesion, and discrete distribution were noted in six (6.7%), 37 (41.6%), and no (0.0%) patients with non-TB pleurisy, respectively. The positive and negative predictive values of any two out of three pleuroscopic patterns for TB pleurisy were 100.0% and 93.7%, respectively.

Conclusions:

A high positive predictive value for TB pleurisy was demonstrated by the presence of any two out of the three characteristic features. Absence of all three features had an excellent negative predictive value for TB pleurisy. Our diagnostic criteria reconfirm that pleuroscopic images can be used as predictors for TB pleurisy in patients with undiagnosed pleural effusion.

The reviews of this paper are available via the supplementary material section.

Optimising the utility of pleural fluid adenosine deaminase for the diagnosis of tuberculous pleural effusion

Introduction:

Pleural fluid adenosine deaminase (pfADA) is a simple, rapid and inexpensive surrogate marker for tuberculous pleural effusion (TPE). A nationwide cut-off of 40 U/L is currently used based on overseas data. There is a need to optimise the diagnostic utility of pfADA by establishing a local cut-off value. In this study, we aimed to describe the demographics and clinical characteristics of patients with TPE and non-TPE; determine the sensitivity and specificity of current pfADA of 40 U/L; and establish a new local pfADA cut-off for TPE.

Methods:

We conducted a single-centre, observational, prospective study of patients with exudative pleural effusion and pfADA measured from 1 October 2019 to 30 April 2020 at Queen Elizabeth Hospital, Malaysia.

Results:

The diagnosis of analysed patients ( n = 93) included TPE ( n = 41), malignancy ( n = 28), parapneumonic effusion ( n = 12) and other causes ( n = 12). The mean pfADA was 51.15 U/L (standard deviation (SD) = 13.77) among TPE group and 18.86 U/L (SD = 12.33) among non-TPE. When analysis was restricted to TPE patients, the local pfADA cut-off is 29.6 U/L, with a sensitivity of 97.6% and specificity of 90.4%. The current pfADA of 40 U/L has a sensitivity of 87.8% and specificity of 92.3%.

Conclusion:

We established a local pfADA cut-off of 29.6 U/L for TPE. Optimising the utility of pfADA helps to enhance clinicians’ treatment confidence of TPE when initial work-up is inconclusive.

Diagnostic Value of Soluble Form of Mer Tyrosine Kinase (sMerTK) in Tuberculous Pleural Effusion and Malignant Pleural Effusion

Objectives. With the development of proteomics, it has been indicated that differentially expressed proteins are biological markers for the diagnosis of different types of pleural effusion (PE). The aim of our study was to explore the value of sMerTK (soluble form of Mer tyrosine kinase) in the differential diagnosis of tuberculous pleural effusion (TPE) and malignant pleural effusion (MPE). In addition, we also wanted to explore whether MerTK was associated with IL-1β and TNF-α, which are inflammatory factors related to pleural effusion. Methods. We screened all patients who underwent thoracoscopy and had a definite diagnosis. In total, 136 patients were enrolled in this study and classified into two groups, with 64 patients in the TPE group and 72 patients in the MPE group. The concentrations of sMerTK in the TPE and MPE groups were detected by ELISA. The diagnostic accuracy was determined by generating receiver operating characteristic (ROC) curves and calculating the area under the curve (AUC). Correlations between the expression level of sMerTK and those of the inflammatory factors interleukin 1 beta (IL-1β) and tumor necrosis factor alpha (TNF-α) were also studied using Pearson’s linear correlation analysis. Results. The concentrations of sMerTK were $\mathrm{5,278.77}\pm \mathrm{2,479.98}\text{ng}/\text{L}$ and $859.91\pm 540.45\text{ng}/\text{L}$ in the TPE and MPE groups, respectively. The concentration of sMerTK in TPE was shown to be significantly higher than that in MPE ( $P<0.05$ ). The area under the ROC curve for sMerTK in distinguishing TPE from MPE was 0.958, with a cutoff value of 2,122 ng/L. The sensitivity and specificity for sMerTK were 98.61% and 90.63% ( $P<0.05$ ). The expression levels of sMerTK in these two groups were not correlated with those of the inflammatory factors IL-1β and TNF-α ( $P>0.05$ ). Conclusions. The expression level of sMerTK in PE could be a potential biomarker for common use in the diagnosis of TPE and MPE.

The epidemiology of extrapulmonary tuberculosis in China: A large-scale multi-center observational study

Tuberculosis (TB) remains a serious global public health problem in the present. TB also affects other sites (extrapulmonary tuberculosis, EPTB), and accounts for a significant proportion of tuberculosis cases worldwide. In order to comprehensively understand epidemiology of EBTB in China, and improve early diagnosis and treatment, we conducted a large-scale multi-center observational study to assess the demographic data and the prevalence of common EPTB inpatients, and further evaluate the prevalence of EPTB concurrent with Pulmonary tuberculosis (PTB) and the associations between multiple EPTB types and gender-age group in China. All consecutive age≥15yr inpatients with a confirmed diagnosis of EPTB during the period from January 2011 to December 2017 were included in the study. The descriptive statistical analysis included median and quartile measurements for continuous variables, and frequencies and proportions with 95% confidence intervals (CIs) for categorical variables. Multinomial logistic regression analysis was used to compare the association of multiple EPTB types between age group and gender. The results showed that the proportion of 15–24 years and 25–34 years in EPTB inpatients were the most and the ratio of male: female was 1.51. Approximately 70% of EPTB inpatients were concurrent with PTB or other types of EPTB. The most common of EPTB was tuberculous pleurisy (50.15%), followed by bronchial tuberculosis (14.96%), tuberculous lymphadenitis of the neck (7.24%), tuberculous meningitis (7.23%), etc. It was found that many EPTB inpatients concurrent with PTB. The highest prevalence of EPTB concurrent with PTB was pharyngeal/laryngeal tuberculosis (91.31%), followed by bronchial tuberculosis (89.52%), tuberculosis of hilar lymph nodes (79.52%), tuberculosis of mediastinal lymph nodes (79.13%), intestinal tuberculosis (72.04%), tuberculous pleurisy (65.31%) and tuberculous meningitis (62.64%), etc. The results from EPTB concurrent with PTB suggested that females EPTB inpatients were less likely to be at higher risk of concurrent PTB (aOR = 0.819, 95%CI:0.803–0.835) after adjusted by age. As age increasing, the trend risk of concurrent PTB decreased (aOR = 0.994, 95%CI: 0.989–0.999) after adjusted by gender. Our study demonstrated that the common EPTB were tuberculous pleurisy, bronchial tuberculosis, tuberculous lymphadenitis of the neck, tuberculous meningitis, etc. A majority of patients with pharyngeal/laryngeal tuberculosis, bronchial tuberculosis, tuberculosis of hilar/mediastinal lymph nodes, intestinal tuberculosis, tuberculous pleurisy, tuberculous meningitis, etc. were concurrent with PTB. Female EPTB inpatients were less likely to be at higher risk of concurrent PTB, and as age increasing, the trend risk of concurrent PTB decreased. The clinicians should be alert to the presence of concurrent tuberculosis in EPTB, and all suspected cases of EPTB should be assessed for concomitant PTB to determine whether the case is infectious and to help for early diagnosis and treatment.

Pleural fluid lactate as a point-of-care adjunct diagnostic aid to distinguish tuberculous and complicated parapneumonic pleural effusions during initial thoracentesis: Potential use in a tuberculosis endemic setting

BACKGROUND

Tuberculous pleural effusions (TBEs) and parapneumonic pleural effusion (PPEs) have similar clinical presentations and fluid biochemistry. A pleural biopsy is usually required to diagnose TBE but complete fluid evacuation may not be necessary, contrasting with complicated PPE (CPPE). A point-of-care test that distinguishes between TBE and CPPE enables the appropriate procedures to be performed during the initial diagnostic thoracentesis. Lactate is a metabolic product measurable by a blood-gas analyzer. This study measured pleural fluid (Pf) lactate levels in TBE and compared them with those in PPE/CPPE. We hypothesized that Pf lactate would be significantly higher in PPE because of active metabolic activities than in TBE which is driven by delayed hypersensitivity.

METHODS

All patients undergoing an initial diagnostic thoracentesis over 18 months with Pf lactate measured using a calibrated point-of-care blood gas analyzer were assessed.

RESULTS

The diagnoses of the enrolled patients (n = 170) included TBE (n = 49), PPE (n = 47), malignancy (n = 63), and transudate (n = 11). Pf lactate level in TBE, median 3.70 (inter-quartile range 2.65-4.90) mmol/l, was significantly lower than in PPE and CPPE. In the subgroup of TBE and CPPE patients whose initial Pf pH and glucose could suggest either condition, Pf lactate was significantly higher in those with CPPE. Pf lactate (cutoff ≥7.25 mmol/l) had a sensitivity of 79.3%, specificity 100%, positive predictive value 100%, and negative predictive value 89.1% for discriminating CPPE from TBE (area under the curve 0.947, p < 0.001, 95% confidence interval 0.89-0.99).

CONCLUSIONS

Point-of-care Pf lactate measurements may have practical value in early separation of TBE or CPPE during initial thoracentesis, and warrants further investigation.

Congestive heart failure is the leading cause of pleural effusion in the north-west of Iran

Introduction: Pleural effusion (PE) is a common manifestation of pulmonary and non–pulmonary diseases, and the first step for diagnosing the etiology is analysis of pleural fluid. The aim of this study was to determine the epidemiology of PE in a tertiary referral hospital in the North-West of Iran.

Methods: All patients with PE who referred to the department of pulmonary diseases in tertiary centre of Tabriz University of Medical Sciences between 2015 and 2016 were enrolled. Complete enumeration method used for selection of patients. Required information including clinical findings, PE location, fluid appearance, and biochemical characteristics were recorded using a checklist and analyzed via appropriate statistical methods.

Results: A total of 223 patients were included in this study. Congestive heart failure (CHF) was the most common cause of PE (n=67), followed by pulmonary thromboembolism and malignant diseases. PE fluid in all patients with CHF was transudative.

Conclusion: According to the findings of this study, CHF was the most prevalent cause of PE.

Clinical value of haptoglobin and soluble CD163 testing for the differential diagnosis of tuberculous and malignant pleural effusions

This study aims to evaluate the clinical value of haptoglobin (Hp) and sCD163 testing for the differential diagnosis of pleural effusion, and investigate the correlation of Hp and sCD163 with the inflammatory response of the body.Pleural effusion samples were collected from 78 patients (38 tuberculous pleural effusions [TPE] and 40 malignant pleural effusions [MPE]). The concentrations of Hp and sCD163 in the pleural effusion were measured by enzyme-linked immunosorbent assay (ELISA).The concentrations of Hp and sCD163 were significantly higher in the TPE group than in the MPE group (P < .05). The sensitivity and specificity of the Hp test for the differential diagnosis of TPE and MPE was 82.4% and 86.1%, respectively (P < .01), while the cut off value was 779.05 ug/mL. Furthermore, the sensitivity and specificity of the sCD163 test for the differential diagnosis of TPE and MPE was 76.3% and 85.0%, respectively (P < .01), while the cut off value was 16,401.11 ng/mL. Moreover, the sensitivity and specificity of the combination of Hp and sCD163 tests for diagnosing TPE was 90.0% and 87.5%, respectively. Hp and IL-1β, TNF-α, CRP and ESR were positively correlated in both the TPE group and MPE group (P < .05). Hp and sCD163 were positively correlated in the TPE group (r = 0.3735, P = .0209), but not in the MPE group (r = 0.22, P = .1684). However, there was no correlation between sCD163 and TNF-α, CRP and ESR in either the TPE group, or the MPE group (P > .05). Furthermore, sCD163 and IL-1β were weakly correlated in the TPE group (r = 0.49, P = .0018), but these had no correlation in the MPE group (r = 0.068, P = .6767).Hp and sCD163 can be used as biological markers for the differential diagnosis of pleural effusion in clinic, and the level of Hp in pleural effusion may reflect the intensity of inflammation in the body to some extent.

An improved algorithm for rapid diagnosis of pleural tuberculosis from pleural effusion by combined testing with GeneXpert MTB/RIF and an anti-LAM antibody-based assay

Background

This retrospective study evaluated the performance of a lipoarabinomannan (LAM)-based immunological method for diagnosing pleural tuberculosis (TB) from pleural effusion samples. Results were compared to those obtained using conventional culture and molecular testing methods.

Methods

Suspected pleural TB patients who visited Beijing Chest Hospital for medical care between January 2016 and June 2017 were retrospectively analysed in the study. Pleural effusion samples were tested for Mycobacterium tuberculosis (MTB) using the BACTEC MGIT 960 System, GeneXpert, and an anti-LAM antibody assay (LAM assay).

Results

Pleural effusion samples were collected from a total of 219 retrospectively recruited participants suspected of having pleural TB. Thirteen of 155 confirmed pleural TB cases tested positive for MTB via MGIT culture, for a sensitivity of 8.4% [95% confidence interval (CI): 4.0–12.8%]. In addition, GeneXpert and LAM testing identified 22 and 55 pleural TB cases, for sensitivities of 14.2% (95% CI: 8.7–19.7%) and 35.5% (95% CI: 28.1–43.6%), respectively. The specificities of these two assays were 100.0% (95% CI: 92.9–100.0%) and 96.9% (95% CI: 88.2–99.5%), respectively. Combined application of culture and LAM testing identified 60 positive cases, for a sensitivity of 38.7% (95% CI: 31.0–46.4%) that was significantly higher than that of MGIT culture alone (P < 0.01). Similarly, use of LAM testing in combination with GeneXpert led to correct diagnosis of 40.0% (95% CI: 32.3–47.7%) of pleural TB cases, a higher rate than obtained using GeneXpert alone (P < 0.01). In addition, the specificity of the combined assay of GeneXpert and LAM testing was 96.9% (95% CI: 88.2–99.5%). Patients aged 25 to 44 years were more likely to have positive LAM assay results than those ≥65 years of age (P = 0.02). Meanwhile, the proportion of diabetic patients with positive LAM assay results was significantly lower than that of the non-diabetes group (P = 0.03).

Conclusions

An anti-LAM antibody detection assay showed potential for diagnosis of pleural TB from pleural effusion samples. Combined use of the LAM assay with MGIT culture or GeneXpert methods could improve sensitivity for improved pleural TB diagnosis compared to results of individual conventional tests alone.

Lymphocytic Pleural Effusion and an Enzyme Involved in Purine Metabolism: A Tertiary Care Experience in Karachi, Pakistan

BACKGROUND

The levels of adenosine deaminase (ADA) are increased in tubercular pleural effusion and its determination has acquired popularity as a diagnostic test which is inexpensive and is readily accessible. Pleural fluid ADA showed sensitivity (86.36%), specificity (61.54%), diagnostic accuracy (80.70%), positive predictive value (88.37%), and negative predictive value (82.42%) confirmed by pleural biopsy as a gold standard.

METHODOLOGY

Our study was a prospective cross-sectional study which was conducted for three years at a tertiary care center in Karachi, Pakistan. The data were collected and analyzed using IBM statistics SPSS vs21.

RESULTS

There were 52 patients included in our study. Twenty one were males and thirty one were females. Most patients presented with shortness of breath. There was a significant association found between raised ADA levels and pulmonary tuberculosis (p < 0.05). The ADA levels are 12 times more likely to be raised in tubercular pleural effusion.

CONCLUSION

The ADA level is an important marker for diagnosis of pulmonary tuberculosis in lymphocytic pleural effusion. It is a convenient and an inexpensive method. The ADA levels assessment is economical when compared to other diagnostic methods.

Etiology, clinical characteristics, and management of pleural effusion in Ilorin, Nigeria

Background:

Pleural effusion (PE) is a primary manifestation or secondary complication of many disorders. This study reviews the pattern and management of PE in a Nigerian hospital.

Materials and Methods:

The medical records of 213 patients with clinical diagnosis of PE over a period of 3 years were reviewed.

Results:

PE accounted for 0.5% of the total hospital admissions. The most common cause of PE was tuberculosis (TB) (32.9%), followed by malignancy (29.1%) and pneumonia (15.0%). The male to female ratio was 1.3:1. TB was the leading cause of effusion in males, while it was malignancy in females. Pneumonia accounted for 61.9% of PE in preschool age and 66.7% in school age. Breathlessness (50.0%), cough (39.4%), and chest pain (24.9%) were the common presentations. Most (90.1%) of them were exudative effusion and with half in the right lung. Chest radiography (91.6%), pleural fluid for Ziehl–Neelsen stain (74.7%), cytology (59.2%), and tissue biopsy (57.8%) were the common diagnostic investigations. The majority (92.0%) had closed thoracostomy tube drainage, while 9.9% had chemical pleurodesis. The intra-hospital mortality was 10 (4.7%).

Conclusion:

TB, malignancy, and pneumonia are the leading causes of PE. A multidisciplinary approach is needed for optimal management.

Clinical and Laboratory Differences between Lymphocyte- and Neutrophil-Predominant Pleural Tuberculosis

Pleural tuberculosis (TB), a form of extrapulmonary TB, can be difficult to diagnose. High numbers of lymphocytes in pleural fluid have been considered part of the diagnostic criteria for pleural TB; however, in many cases, neutrophils rather than lymphocytes are the predominant cell type in pleural effusions, making diagnosis more complicated. Additionally, there is limited information on the clinical and laboratory characteristics of neutrophil-predominant pleural effusions caused by Mycobacterium tuberculosis (MTB). To investigate clinical and laboratory differences between lymphocyte- and neutrophil-predominant pleural TB, we retrospectively analyzed 200 patients with the two types of pleural TB. Of these patients, 9.5% had neutrophil-predominant pleural TB. Patients with lymphocyte-predominant and neutrophil-predominant pleural TB showed similar clinical signs and symptoms. However, neutrophil-predominant pleural TB was associated with significantly higher inflammatory serum markers, such as white blood cell count (P = 0.001) and C-reactive protein (P = 0.001). Moreover, MTB was more frequently detected in the pleural fluid from patients in the neutrophil-predominant group than the lymphocyte-predominant group, with the former group exhibiting significantly higher rates of positive results for acid-fast bacilli in sputum (36.8 versus 9.4%, P = 0.003), diagnostic yield of MTB culture (78.9% versus 22.7%, P < 0.001) and MTB detected by polymerase chain reaction (31.6% versus 5.0%, P = 0.001). Four of seven patients with repeated pleural fluid analyses revealed persistent neutrophil-predominant features, which does not support the traditional viewpoint that neutrophil-predominant pleural TB is a temporary form that rapidly develops into lymphocyte-predominant pleural TB. In conclusion, neutrophil-predominant pleural TB showed a more intense inflammatory response and a higher positive rate in microbiological testing compared to lymphocyte-predominant pleural TB. Pleural TB should be considered in neutrophil-predominant pleural effusions, and microbiological tests are warranted.

A combination of the QuantiFERON-TB Gold In-Tube assay and the detection of adenosine deaminase improves the diagnosis of tuberculous pleural effusion

The differential diagnosis of tuberculous pleural effusion (TPE) and malignant pleural effusion (MPE) remains difficult despite the availability of numerous diagnostic tools. The current study aimed to evaluate the performance of the whole blood QuantiFERON-TB Gold In-Tube (QFT-GIT) assay and conventional laboratory biomarkers in differential diagnosis of TPE and MPE in high tuberculosis prevalence areas. A total of 117 patients with pleural effusions were recruited, including 91 with TPE and 26 with MPE. All of the patients were tested with QFT-GIT, and the conventional biomarkers in both blood and pleural effusion were detected. The level of antigen-stimulated QFT-GIT in the whole blood of TPE patients was significantly higher than that of MPE (2.89 vs 0.33 IU/mL, P<0.0001). The sensitivity and specificity of QFT-GIT for the diagnosis of TPE were 93.0% and 60.0%, respectively. Among the biomarkers in blood and pleural effusion, pleural adenosine deaminase (ADA) was the most prominent biomarker, with a cutoff value of 15.35 IU/L. The sensitivity and specificity for the diagnosis of TPE were 93.4% and 96.2%, respectively. The diagnostic classification tree from the combination of these two biomarkers was 97.8% sensitive and 92.3% specific. Ultimately, the combination of whole blood QFT-GIT with pleural ADA improved both the specificity and positive predictive value to 100%. Thus, QFT-GIT is not superior to pleural ADA in the differential diagnosis of TPE and MPE. Combined whole blood QFT-GIT and pleural ADA detection can improve the diagnosis of TPE.

Status of Exudative Pleural Effusion in Adults of South Khorasan Province, Northeast Iran: Pleural Tuberculosis Tending toward Elderly

The causes and situation of exudative pleural effusion vary from one area to another. A cross-sectional study was conducted on 327 patients with exudative pleural effusion in South Khorasan province (Iran). The patients were older than 12 years and comprised 172 (52.6%) males and 155 (47.4%) females. The study commenced in 2007 with seven years duration. The Light's criteria were used to define exudative effusion. Procedures including pleural fluid analysis, microbiological study, pleural biopsy, and systemic investigations were conducted to determine the special cause of pleural effusion. The mean age of the patients was 63.4±18.4 years. Malignancies, tuberculosis, and parapneumonia pleural exudation were diagnosed in 125 (38.2%), 48 (14.7%), and 45 (13.8%) cases, respectively. Among malignant effusions, metastasis from lung cancer made 48 (38.4%) of the cases. The origin of metastasis was not determined in 44 (35.2%) patients. The mean age of patients was not significantly different between malignant (66.9±14.3 years) and tuberculosis (63.9±19.7 years) cases (P=0.16). The older age of tuberculosis patients could be a new discussion point on the overall impression created on the subject of tuberculosis pleural exudation (TB-PLE) occurring in young people.

Yield of closed pleural biopsy and cytology in exudative pleural effusion

Objective:

To determine diagnostic yield of Closed Pleural Biopsy (CPB) and Cytology in Exudative Pleural Effusion (PE).

Methods:

This prospective comparative study was conducted at Chest Unit-II & Medical Unit-IV of Dow University of Health Sciences, Karachi Pakistan from January 2011 till December 2014.

Results:

Ninety-four patients with exudative PE were finally included. The mean age (SD) was 44.0 (13.8) years. Overall Specific Diagnosis was reached in 76/94 patients; 46 Tuberculosis PE (TPE) & 30 Malignant PE (MPE). CPB diagnosed all TPE patients alone and 28/30 of MPE. Cytology diagnosed only 10/30 patients of MPE with 8 patients having both CPB & Cytology positive for malignancy whereas in the remaining two cases only Cytology positive. The sensitivity of CPB in detecting TPE and MPE was 93.9% and 82.4% respectively whereas specificity for both was 100%. The diagnostic yield of cytology in detecting MPE is only (33.3%). The diagnostic yield of CPB for TPE and MPE is 100% and 93.3% respectively. The overall specific diagnostic yield of CPB is 78.7%.

Conclusion:

CPB is better than pleural fluid cytology alone with the later adding little to diagnostic yield when both combined in distinguishing TPE from MPE, the two main differential of exudative PE in a TB-Endemic country.

Massive Pleural Fluid Collection in Adult Nigerians

Background. There are no available literatures on massive pleural effusions (MPE) in our country. Aim. To determine the aetiology of MPE and compare the mortality rate between malignant and nonmalignant MPE in adult Nigerians. Methods. A prospective study of all the patients diagnosed with nontraumatic pleural fluid collections for one year in two tertiary federal hospitals in Southern Nigeria. A total of 101 consecutive patients with pleural fluid collections were studied. Diagnoses were made by clinical features and laboratory and radiological investigations. Results. Forty-eight patients (47.5%) had MPE with a mean age of 43 years ± 14.04 and 35 were females. Thirty patients (62.5%) were diagnosed with nonmalignant conditions (21 from pulmonary tuberculosis (PTB) and 9 from other causes). Haemorrhagic pleural collections were from malignancy in 12 (30.8%) and from PTB in 6 (15.4%). Straw-coloured collections were from malignancy in 9 (23.1%), from PTB in 8 (20.1%), and from posttraumatic exudative effusion in 3 (7.7%). Compared with nonmalignant MPE, patients with malignant collections had higher mortality within 6 months (8/18 versus 0/30 with a P value of 0.000). Conclusion. The presentation of patients with nontraumatic haemorrhagic or straw-coloured MPE narrows the diagnosis to PTB and malignancy with MPE cases being a marker for short survival rate.

Expression of YKL-40 and MIP-1a proteins in exudates and transudates: biomarkers for differential diagnosis of pleural effusions? A pilot study

Background

YKL-40 is an extracellular matrix glycoprotein with a significant role in tissue inflammation and remodeling. MIP-1a has chemotactic and pro-inflammatory properties, and is induced by YKL-40 in several lung disorders. The aim of this study was to determine the levels of YKL-40 and MIP-1a in blood serum and pleural fluids of various pulmonary diseases, and to evaluate their potential role as differential diagnosis biomarkers.

Methods

We recruited 60 patients (age: 62.5 ± 20.6 years) with pleural effusions: 49 exudates and 11 transudates (T). Exudates were further classified based on the underlying disease: ten with tuberculosis (TB), 13 with lung cancer (LCa), 15 with metastatic cancer (MCa) of non-lung origin and 11 with parapneumonic (PN) effusions. YKL-40 and MIP-1a levels were measured by ELISA.

Results

Pleural YKL-40 levels (ng/ml) were similar among all patient groups (TB: 399 ± 36, LCa: 401 ± 112, MCa: 416 ± 34, PN: 401 ± 50, T: 399 ± 42, p = 0.92). On the contrary, YKL-40 was significantly lower in the serum of TB patients (TB: 58 ± 22, LCa: 212 ± 106, MCa: 254 ± 140, PN: 265 ± 140, T: 229 ± 123, p < 0.001). Pleural MIP-1a protein levels (ng/ml) were statistically lower only in patients with LCa (TB: 25.0 ± 20.2, LCa: 7.3 ± 6.0, MCa: 16.1 ± 14.9, PN: 25.4 ± 27.9, T: 18.5 ± 7.9, p = 0.012), a finding also observed in serum MIP-1a levels (TB: 17.1 ± 7.6, LCa: 9.4 ± 7.0, MCa: 28.7 ± 28.7, PN: 33.3 ± 24.0, T: 22.9 ± 8.7, p = 0.003).

Conclusions

Our data suggest that both YKL-40 and MIP-1a, particularly in serum, could prove useful for the differentiation of pleural effusions in clinical practice, especially of TB or LCa origin. However, large-scale studies are needed to validate these findings.

Automatic detection of pleural effusion in chest radiographs

Automated detection of Tuberculosis (TB) using chest radiographs (CXRs) is gaining popularity due to the lack of trained human readers in resource limited countries with a high TB burden. The majority of the computer-aided detection (CAD) systems for TB focus on detection of parenchymal abnormalities and ignore other important manifestations such as pleural effusion (PE). The costophrenic angle is a commonly used measure for detecting PE, but has limitations. In this work, an automatic method to detect PE in the left and right hemithoraces is proposed and evaluated on a database of 638 CXRs. We introduce a robust way to localize the costophrenic region using the chest wall contour as a landmark structure, in addition to the lung segmentation. Region descriptors are proposed based on intensity and morphology information in the region around the costophrenic recess. Random forest classifiers are trained to classify left and right hemithoraces. Performance of the PE detection system is evaluated in terms of recess localization accuracy and area under the receiver operating characteristic curve (AUC). The proposed method shows significant improvement in the AUC values as compared to systems which use lung segmentation and the costophrenic angle measurement alone.

Comparison of MGIT and Myco/F lytic liquid-based blood culture systems for recovery of Mycobacterium tuberculosis from pleural fluid

The specificities and sensitivities of the Bactec mycobacterial growth indicator tube (MGIT) system for the recovery of Mycobacterium tuberculosis from pleural fluid are not statistically different than those of the Myco/F lytic liquid culture system. The time to positivity is shorter in the MGIT system (12.7 versus 20.7 days, respectively; P=0.007). The Myco/F lytic culture system may be an alternative to the MGIT system for diagnosing pleural tuberculosis.

Age and sex distribution in malignant and tuberculous serous effusions: A study of 127 patients and review of the literature

AIM

Tuberculosis and carcinomatosis are the two most frequent causes of pleural effusion and exudative ascites, and both are characterized by lymphocyte-rich effusion. We attempted to discover if there is any significant difference in the age and sex distribution between patients presenting with these two conditions.

METHODS

A total of 161 serous effusion samples from 127 patients (89 with pleural effusion and 38 with ascites) having follow-up biopsy and histopathological examination were included in the present study. Three groups - malignancy (47 patients), tuberculosis (47) and non-tuberculous benign lesions (26) as per histopathological diagnoses - were compared in respect to age and sex distribution.

RESULTS

A total of 29 (61.7%) patients with malignancy were aged ≥50 years as compared with three (6.4%) tuberculosis patients with serous effusions (P = 0.00000). A similar trend was observed in the ≥60 years age group (18 or 38.3% malignancy vs none with tuberculosis, P = 0.00000). A total of 36 (76.6%) tuberculous effusion patients were aged less than 40 years as opposed to eight (17.0%) patients with malignant effusions (P = 0.00000). There was also s significant difference between tuberculous and non-tuberculous benign lesions in the ≥50 years age group (6.4% vs 69.2%, P = 0.00000), but no significant difference between malignancy and non-tuberculous benign lesions (P = 0.61385). There were 31 female (66.0%) patients with malignancy, which was significantly higher than that of patients with tuberculosis (16, [34%], P = 0.00365) and non-specific inflammation/benign lesions (23.1%, P = 0.00059). However, the difference between tuberculosis and non-tuberculous benign lesions was not significant (P = 0.42756).

CONCLUSION

Whereas malignancy in serous effusions is found in older and middle-aged people, tuberculous effusion is a disease of younger people.

Diagnostic accuracy of tumor necrosis factor-alpha, interferon-gamma, interleukin-10 and adenosine deaminase 2 in differential diagnosis between tuberculous pleural effusion and malignant pleural effusion

Background

The current study was performed to investigate the potential biomarkers for the differential diagnosis of tuberculous pleural effusion (TPE) and malignant pleural effusions (MPE).

Methods

Among ninety patients (n = 90) involved in the study, 47 with tuberculous pleural effusion aged from 18 to 70 and 43 with secondary malignant pleural effusion aged from 34 to 78. We tested the pleural levels of TNF-α, IFN-γ and IL-10 as well as the enzyme activity of ADA₂, and then we compared the differential diagnostic efficiencies of those biochemical parameters with ADA between the two groups.

Results

Our results show that, the concentrations of pleural TNF-α (45.55 ± 15.85 ng/L), IFN-γ (114.97 ± 27.85 ng/L) as well as activities of ADA₂ (35.71 ± 10.00 U/L) and ADA (39.39 ± 10.60 U/L) in tuberculous group were significantly higher compared to malignant group. Furthermore, according to the ROC curve analysis the thresholds of TNF-α, IFN-γ, ADA₂ and ADA were found to be 30.3 ng/L, 103.65 ng/L, 29.45 U/L, and 39.00 U/L, respectively. TNF-α, IFN-γ and ADA₂ yielded better sensitivity, specificity, and accuracy of the diagnosis than ADA. Our investigation further revealed that the combinations of TNF-α and ADA₂ further increased the specificity and accuracy for the differential diagnosis.

Conclusion

In conclusion, we found that TNF-α, IFN-γ, ADA and ADA₂ all increased in TPE. Combinations of the TNF-α and ADA₂ yielded the best specificity and accuracy for the differential diagnosis of TPE from MPE. Our investigation suggests that the applications of TNF-α together with ADA₂ may contribute to more efficient diagnosis strategies in the management of discrimination between tuberculous and malignant pleural effusions.

Role of common investigations in aetiological evaluation of exudative pleural effusions

BACKGROUND

Pleural effusion is a common problem encountered in daily practice. To Establish aetiology of exudative effusions is a diagnostic challenge to general practitioners and even to pulmonologists especially in resource poor government hospitals with lack of investigations like thoracoscopy. Some recent studies had shown that around 2% of patients remained undiagnosed even after these investigations.

AIMS AND OBJECTIVE

To evaluate the role of the commonly available investigations such as pleural fluid study, blind pleural biopsy, sputum examination, CT scan thorax, bronchoscopy in the aetiological evaluation of exudative effusions and to ascertain the proportion of cases which remain undiagnosed after all the above investigations.

MATERIAL AND METHODS

This was a prospective single-centred cross-sectional study carried out at the NRS Medical College, Kolkata, India from February 2008 to February 2013 which included 568 patients of exudative pleural effusions. We performed commonly available procedures like pleural fluid study, blind pleural biopsy, sputum examination, CT scan thorax, bronchoscopic procedures to the diagnosis.

RESULTS

Total number of patients studied were 568. Tuberculosis was the most common cause (54.57%) followed by malignancy (28.17%), empyema (10.56%), parapneumonic effusion (5.28%) and others. Carcinoma of the lung was the commonest cause of malignant effusions and bronchoscopic biopsy was given the highest yield of histological diagnosis (84.6%) followed by CT guided FNAC (77.6%) and pleural fluid cytology (55%). Highest yield to diagnose tubercular effusion was found in lymph node FNAC (81.5%) followed by pleural biopsy (62%). Sputum smear for AFB was positive in only 27.4% cases. Bleeding followed by pneumothorax were the most common complications. Complications are very less (1.3% and 0.9% respectively). 2 patients (0.34%) remained undiagnosed even after these all above said investigations.

CONCLUSION

Above mentioned commonly available investigations can ascertain diagnosis in most of the cases in the aetiological evaluation of exudative effusions and they are relatively safe procedures.

Factors affecting pleural fluid adenosine deaminase level and the implication on the diagnosis of tuberculous pleural effusion: a retrospective cohort study

Background

Adenosine deaminase (ADA) is useful in the diagnosis of tuberculous pleural effusion (TPE). This study aims to determine the factors affecting pleural fluid ADA levels and to establish the optimal ADA levels for diagnosis of TPE for different age groups.

Methods

This was a retrospective study from January 2007 to October 2011. One hundred and sixty patients who had pleural fluid ADA performed for investigation of pleural effusion were analyzed. Variables examined included demographics, pleural fluid characteristics and peripheral blood counts. The ADA cut-offs according to age were selected using the receiver operating characteristic (ROC) curve.

Results

The mean pleural fluid ADA was significantly higher in the TPE group (100 ± 35 IU/L) compared to non TPE patients (30 ± 37 IU/L). There was significant correlation between pleural fluid ADA and age, pleural fluid protein, LDH, and fluid absolute lymphocyte count. The strongest correlation was seen with age (r = −0.621). For patients ≤ 55 years old the ROC for ADA had area under curve (AUC) of 0.887. A pleural fluid ADA of 72 IU/L had sensitivity of 95.1%, specificity of 87.5%, positive predictive value (PPV) of 95.1% and negative predictive value (NPV) of 87.5% for the diagnosis of TPE. For patients > 55 years old the AUC is 0.959. ADA of 26 IU/L had a sensitivity of 94.7%, specificity of 80.4%, PPV of 62% and NPV of 97.8%.

Conclusions

There is a significant negative correlation between pleural fluid ADA and age. For older patients, a lower ADA cut-off should be used to exclude TPE.

Pleural fluid cholesterol in differentiating exudative and transudative pleural effusion

Objectives. To study the diagnostic value of pleural fluid cholesterol in differentiating transudative and exudative pleural effusion. To compare pleural fluid cholesterol level for exudates with Light's criteria. Design. Cross sectional descriptive study. Settings. Medical wards of Tribhuvan University Teaching Hospital. Methods. Sixty two cases of pleural effusion with definite clinical diagnosis admitted in TUTH were taken and classified as transudates (19) and exudates (43). The parameters pleural fluid protein/serum protein ratio (pfP/sP), pleural fluid LDH/ serum LDH ratio, pleural fluid LDH (pfLDH) and pleural fluid cholesterol (pCHOL) were compared with clinical diagnosis with regard to their usefulness for distinguishing between pleural exudates and transudates. Results. The pCHOL values determined were 1.92 ± 0.75 for exudates, 0.53 ± 0.28 for transudates, the differences between the transudates and others are statistically significant (P < 0.0001). It is seen that pfP/sP ratio has a sensitivity of 81.4% and specificity of 82.6%; pfLDH/sLDH ratio has a sensitivity of 86% and specificity of 94.7% and pCHOL with sensitivity of 97.7% and specificity of 100% for differentiating exudative and transudative PE. Conclusion. The determination of pCHOL is of great value for distinguishing between pleural exudates and transudates and should be included in routine laboratory analysis of pleural effusion.

Amplified Mycobacterium tuberculosis direct test for diagnosing tuberculous pleurisy--a diagnostic accuracy study

BACKGROUND

The study was designed to investigate the clinical usefulness of Amplified Mycobacterium Tuberculosis Direct (AMTD) tests for diagnosing TB pleurisy.

METHODS

One hundred and fifty-two patients for whom the exclusion of tuberculous pleural effusion was necessary were retrospectively analyzed.

RESULTS

The sensitivity of AMTD in diagnosing pleural TB was 36.4% (20 of 55). Combining sputum and pleural effusion AFB smear, pleural biopsy, and AMTD test of pleural effusion increased sensitivity to 82.5% (33/40). There were significantly higher percentages of neutrophils in the pleural effusion in the positive than in the negative AMTD group (38.0 ± 6.7% vs. 11.1 ± 3.7%, p<0.001). Patients with symptom duration <18 days prior to pleural effusion studies had more positive AMTD tests than those with symptom >18 days (70% vs. 31.4%; OR 5.09; 95% CI 1.54-16.79; p = 0.011).

CONCLUSIONS

Combining AMTD tests with conventional diagnostic methods offer good sensitivity for pleural TB diagnosis. Patients in the early course of the disease are better candidates for AMTD tests.

Revisiting tuberculous pleurisy: pleural fluid characteristics and diagnostic yield of mycobacterial culture in an endemic area

BACKGROUND

Tuberculous pleurisy is traditionally indicated by extreme lymphocytosis in pleural fluid and low yield of effusion culture. However, there is considerable inconsistency among previous study results. In addition, these data should be updated due to early effusion studies and advances in culture methods.

METHODS

From January 2004 to June 2009, patients with tuberculous pleurisy were retrospectively identified from the mycobacteriology laboratories and the pathology and tuberculosis registration databases of two hospitals in Taiwan where tuberculosis is endemic. Pleural fluid characteristics and yields of mycobacterial cultures using liquid media were evaluated.

RESULTS

A total of 382 patients with tuberculous pleurisy were identified. The median lymphocyte percentage of total cells in pleural fluids was 84% (IQR 64-95%) and 17% of cases had a lymphocyte percentage of <50%. The lymphocyte percentage was negatively associated with the probability of a positive effusion culture (OR 0.97; 95% CI 0.96 to 0.99). The diagnostic yields were 63% for effusion culture, 48% for sputum culture, 79% for the combination of effusion and sputum cultures, and 74% for histological examination of pleural biopsy specimens.

CONCLUSION

The degree of lymphocyte predominance in tuberculous pleurisy was lower than was previously thought. The lymphocyte percentage in pleural fluid was negatively associated with the probability of a positive effusion culture. With the implementation of a liquid culture method, the sensitivity of effusion culture was much higher than has been previously reported, and the combination of effusion and sputum cultures provided a good diagnostic yield.

Differential proteome profiling of pleural effusions from lung cancer and benign inflammatory disease patients

The pleural effusion proteome has been found containing information that directly reflects pathophysiological status and represents a potential diagnostic value for pulmonary diseases. However, the variability in protein composition between malignant and benign effusions is not well understood. Herein, we investigated the changes of proteins in pleural effusions from lung adenocarcinoma and benign inflammatory disease (pneumonia and tuberculosis) patients by two-dimensional difference gel electrophoresis (2D-DIGE). Twenty-eight protein spots displayed significantly different expression levels were positively identified by MALDI-TOF-MS representing 16 unique proteins. Five identified protein candidates were further validated and analyzed in effusions, sera or tissues. Among them, hemopexin, fibrinogen gamma and transthyretin (TTR) were up-regulated in cancer samples. The effusion concentration of serum amyloid P component (SAP) was significantly lower in lung cancer patients than in benign inflammatory patients, but no differences were found in sera samples. Moreover, a Jumonji C (JmjC)-domain-containing protein, JMJD5, was observed to be down-regulated in malignant effusions, lung cancer tissues and cancer cells. These results shed light on the altered pleural effusion proteins as a useful and important complement to plasma or other routine clinical tests for pulmonary disease diagnosis.

Assessment of the N-PCR assay in diagnosis of pleural tuberculosis: detection of M. tuberculosis in pleural fluid and sputum collected in tandem

BACKGROUND

The nonspecific clinical presentation and paucibacillary nature of tuberculous pleuritis remains a challenge for diagnosis. Diagnosis of tuberculous pleural effusion depends on the demonstration of the presence of tubercle bacilli in the sputum, pleural fluid, or pleural biopsy specimen, or demonstration of granuloma in pleura by histological examination. We examined the clinical utility of the diagnosis of pleural tuberculosis using the in house N-PCR assay, AFB smear microscopy and culture. Besides pleural fluid the inclusion of sputum in the efficacy of diagnosis of pleural tuberculosis was scrutinized.

METHODOLOGY/PRINCIPAL FINDINGS

Pleural fluid and sputum samples of 58 tuberculous and 42 non-tuberculous pleural effusion patients were processed for AFB smear microscopy, culture and the N-PCR assay. Mycobacteria were detected exclusively in tuberculous pleural effusion samples. None of the non-tuberculous pleural effusion samples were positive for mycobacteria. Comparative analysis showed that the N-PCR assay had the highest sensitivity. Inclusion of sputum along with pleural fluid increased N-PCR sensitivity from 51.7 to 70.6% (p<0.0001).This improved sensitivity was reflected in AFB smear microscopy and isolation by culture. The sensitivity enhanced on inclusion of sputum from 3.4 (p = 0.50) to 10.3% (p = 0.038) for AFB smear microscopy and for isolation of mycobacteria from 10.3(p = 0.03) to 22.4% (p = 0.0005). Thirteen isolates were obtained from 58 pleural tuberculosis patients. Eleven mycobacterial isolates were identified as M. tuberculosis and two as M. fortuitum and M. chelonae. Complete concordance was seen between the biochemical identification of isolates and the N-PCR identification of mycobacterial species prior to isolation.

CONCLUSIONS/SIGNIFICANCE

To the best of our knowledge this is the first PCR based report on utility of sputum for diagnosis of pleural tuberculosis. The present study demonstrates that a combination of pleural fluid with sputum sample and N-PCR improved the diagnosis of pleural tuberculosis.

Nucleic acid amplification tests in the diagnosis of tuberculous pleuritis: a systematic review and meta-analysis

Background

Conventional tests for tuberculous pleuritis have several limitations. A variety of new, rapid tests such as nucleic acid amplification tests – including polymerase chain reaction – have been evaluated in recent times. We conducted a systematic review to determine the accuracy of nucleic acid amplification (NAA) tests in the diagnosis of tuberculous pleuritis.

Methods

A systematic review and meta-analysis of 38 English and Spanish articles (with 40 studies), identified via searches of six electronic databases, hand searching of selected journals, and contact with authors, experts, and test manufacturers. Sensitivity, specificity, and other measures of accuracy were pooled using random effects models. Summary receiver operating characteristic curves were used to summarize overall test performance. Heterogeneity in study results was formally explored using subgroup analyses.

Results

Of the 40 studies included, 26 used in-house ("home-brew") tests, and 14 used commercial tests. Commercial tests had a low overall sensitivity (0.62; 95% confidence interval [CI] 0.43, 0.77), and high specificity (0.98; 95% CI 0.96, 0.98). The positive and negative likelihood ratios for commercial tests were 25.4 (95% CI 16.2, 40.0) and 0.40 (95% CI 0.24, 0.67), respectively. All commercial tests had consistently high specificity estimates; the sensitivity estimates, however, were heterogeneous across studies. With the in-house tests, both sensitivity and specificity estimates were significantly heterogeneous. Clinically meaningful summary estimates could not be determined for in-house tests.

Conclusions

Our results suggest that commercial NAA tests may have a potential role in confirming (ruling in) tuberculous pleuritis. However, these tests have low and variable sensitivity and, therefore, may not be useful in excluding (ruling out) the disease. NAA test results, therefore, cannot replace conventional tests; they need to be interpreted in parallel with clinical findings and results of conventional tests. The accuracy of in-house nucleic acid amplification tests is poorly defined because of heterogeneity in study results. The clinical applicability of in-house NAA tests remains unclear.

The masquerades of female pelvic tuberculosis: case reports and review of literature on clinical presentations and diagnosis

In this review, tuberculosis of the genital tract was diagnosed retrospectively in 11 females over 15 years. The presentations of nine cases are described. Seven of the nine cases presented with ascites, vague abdominal distension, weight loss and were misdiagnosed as ovarian carcinoma. Eight women had no relevant past history. A review on clinical presentations and diagnosis of pelvic tuberculosis is presented. We conclude that although the incidence of tuberculosis is uncommon in developed countries, its prevalence appears to be increasing worldwide. Therefore, clinicians should consider tuberculosis as a differential diagnosis when encountering clinical presentations of pelvic mass and ascites.

Common causes of pleural effusion in referral hospital in Isfahan, Iran 1997-1998

During a one-year period to September 1998, data were collected from all 213 patients referred with pleural effusion. There were 132 males and 81 females; their ages ranged from 18 to 85 years. The most common etiologies of effusion were congestive heart failure (39.4%), malignancy (27.2%), pneumonia (8%), empyema (5.2%), and tuberculosis (5.2%). Pleural effusions are frequent in Iran, and the causes are fairly similar to those reported by European authors, but with slightly more tuberculosis cases, mostly among Afghan refugees.