Pleural tuberculosis

Diagnosis and Management of Tuberculous Pleural Effusion in a Patient With Chronic Obstructive Pulmonary Disease: A Case Report

A 63-year-old man had been smoking bidis for 25 years and developed tubercular empyema, further complicated by pneumothorax and other pulmonary issues. Over a period of three weeks, the individual experienced a gradual onset of symptoms, including progressive shortness of breath, cough, fever, and chest pain. Radiographic examinations revealed significant left-sided pleural effusion with consolidation and evidence of pneumothorax. Other findings included anemia, hyponatremia, substantially increased lactate dehydrogenase, and adenosine deaminase (ADA), consistent with tubercular or chronic infection. The comprehensive treatment plan involved the administration of antibiotics, antitubercular drugs, draining of the pleural fluid, nebulized bronchodilators, corticosteroids, and broad-spectrum antibiotics. The patient exhibited a positive response, showing notable clinical improvement, which was closely monitored through sequential chest X-rays and ECGs. This would continue to highlight the vital need for early tuberculosis detection in patients with chronic obstructive pulmonary disease due to clinical overlap with other diseases. To diagnose and follow up on tuberculous pleural effusion cases, it was critical to integrate both clinical and radiographic findings with laboratory data. It emphasizes the necessity for a multidisciplinary approach to improve overall treatment outcomes.

Hepatocyte growth factor combined with adenosine deaminase as biomarker for diagnosis of tuberculous pleural effusion

Background

The simple, rapid, and accurate diagnosis of tuberculous pleural effusion (TPE) remains difficult. This study aimed to determine the accuracy of hepatocyte growth factor (HGF) in the diagnosis of TPE.

Methods

We quantified the expression of HGF, adenosine deaminase (ADA), and interferon gamma (IFN-γ) in pleural effusion (PE) in 97 TPE subjects and 116 non-TPE subjects using an enzyme-linked immunosorbent assay (ELISA) or a fully automatic biochemical analyzer. The diagnostic performance of these three biomarkers was evaluated using a receiver operating characteristic (ROC) curve of subjects by age and gender.

Results

We discovered that the TPE group had much higher levels of HGF than the non-TPE group, regardless of age or gender, and that there was no statistically significant difference between the two groups' levels of HGF expression in peripheral plasma. In female TPE patients aged ≤65 years, the AUCs of TPE and non-TPE diagnosed by HGF, ADA or IFN-γ were 0.988, 0.964, and 0.827, respectively. HGF plus ADA had the highest diagnostic efficacy in female TPE patients aged ≤65 years. With HGF plus ADA having a cut-off value of 0.219 for distinguishing TPE from non-TPE, the area under the curve (AUC), sensitivity (SEN), specificity (SPE), positive predictive value (PPV), and negative predictive value (NPV) were, respectively, 0.998 (95% confidence interval [CI], 0.993-1.000), 100 (95% CI, 89.997-100.000), 96.667 (95% CI, 82.783-99.916), 97.222 (95% CI, 83.594-99.586), and 100.

Conclusion

This study confirmed that HGF plus ADA has high diagnostic efficacy in younger female TPE patients and has the potential to be an excellent biomarker.

Insight into diagnosis of pleural tuberculosis with special focus on nucleic acid amplification tests

INTRODUCTION

Pleural tuberculosis (TB) is the archetype of extrapulmonary TB (EPTB), which mainly affects the pleural space and leads to exudative pleural effusion. Diagnosis of pleural TB is a difficult task predominantly due to atypical clinical presentations and sparse bacillary load in clinical specimens.

AREA COVERED

We reviewed the current literature on the globally existing conventional/latest modalities for diagnosing pleural TB. Bacteriological examination (smear/culture), tuberculin skin testing/interferon-γ release assays, biochemical testing, imaging and histopathological/cytological examination are the main modalities. Moreover, nucleic acid amplification tests (NAATs), i.e. loop-mediated isothermal amplification, PCR/multiplex-PCR, nested-PCR, real-time PCR and GeneXpert® MTB/RIF are being utilized. Currently, GeneXpert Ultra, Truenat MTB^TM, detection of circulating Mycobacterium tuberculosis (Mtb) cell-free DNA by NAATs, aptamer-linked immobilized sorbent assay and immuno-PCR (I-PCR) have also been exploited.

EXPERT OPINION

Routine tests are not adequate for effective pleural TB diagnosis. The latest molecular/immunological tests as discussed above, and the other tools, i.e. real-time I-PCR/nanoparticle-based I-PCR and identification of Mtb biomarkers within urinary/serum extracellular vesicles being utilized for pulmonary TB and other EPTB types may also be exploited to diagnose pleural TB. Reliable diagnosis and early therapy would reduce the serious complications associated with pleural TB, i.e. TB empyema, pleural fibrosis, etc.

Complement Component C1q as an Emerging Biomarker for the Diagnosis of Tuberculous Pleural Effusion

Background and Objective: The accurate differential diagnosis of tuberculous pleural effusion (TPE) from other exudative pleural effusions is often challenging. We aimed to validate the accuracy of complement component C1q in pleural fluid (PF) in diagnosing TPE. Methods: The level of C1q protein in the PF from 49 patients with TPE and 61 patients with non-tuberculous pleural effusion (non-TPE) was quantified by enzyme-linked immunosorbent assay, and the diagnostic performance was assessed by receiver operating characteristic (ROC) curves based on the age and gender of the patients. Results: The statistics showed that C1q could accurately diagnose TPE. Regardless of age and gender, with a cutoff of 6,883.9 ng/mL, the area under the curve (AUC), sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of C1q for discriminating TPE were 0.898 (95% confidence interval: 0.825-0.947), 91.8 (80.4-97.7), 80.3 (68.2-89.4), 78.9 (69.2-86.2), and 92.5 (82.6-96.9), respectively. In subgroup analysis, the greatest diagnostic accuracy was achieved in the younger group (≤ 50 years of age) with an AUC of 0.981 (95% confidence interval: 0.899-0.999) at the cutoff of 6,098.0 ng/mL. The sensitivity, specificity, PLR, NLR, PPV, and NPV of C1q were 95.0 (83.1-99.4), 92.3 (64.0-99.8), 97.4 (85.2-99.6), and 85.7 (60.6-95.9), respectively. Conclusion: Complement component C1q protein was validated by this study to be a promising biomarker for diagnosing TPE with high diagnostic accuracy, especially among younger patients.

Extrapulmonary Tuberculosis—An Update on the Diagnosis, Treatment and Drug Resistance

Pathogenic Mycobacterium tuberculosis complex organisms (MTBC) primarily cause pulmonary tuberculosis (PTB); however, MTBC are also capable of causing disease in extrapulmonary (EP) organs, which pose a significant threat to human health worldwide. Extrapulmonary tuberculosis (EPTB) accounts for about 20–30% of all active TB cases and affects mainly children and adults with compromised immune systems. EPTB can occur through hematogenous, lymphatic, or localized bacillary dissemination from a primary source, such as PTB, and affects the brain, eye, mouth, tongue, lymph nodes of neck, spine, bones, muscles, skin, pleura, pericardium, gastrointestinal, peritoneum, and the genitourinary system as primary and/or disseminated disease. EPTB diagnosis involves clinical, radiological, microbiological, histopathological, biochemical/immunological, and molecular methods. However, only culture and molecular techniques are considered confirmatory to differentiate MTBC from any non-tuberculous mycobacteria (NTM) species. While EPTB due to MTBC responds to first-line anti-TB drugs (ATD), drug susceptibility profiling is an essential criterion for addressing drug-resistant EPTB cases (DR-EPTB). Besides antibiotics, adjuvant therapy with corticosteroids has also been used to treat specific EPTB cases. Occasionally, surgical intervention is recommended, mainly when organ damage is debilitating to the patient. Recent epidemiological studies show a striking increase in DR-EPTB cases ranging from 10–15% across various reports. As a neglected disease, significant developments in rapid and accurate diagnosis and better therapeutic interventions are urgently needed to control the emerging EPTB situation globally. In this review, we discuss the recent advances in the clinical diagnosis, treatment, and drug resistance of EPTB.

Diagnostic Accuracy of Pleural Effusion Mononuclear Cells/Leukocyte Ratio in Tuberculous Pleurisy

Background: Tuberculous pleurisy (TBP) is a common clinical type of tuberculosis (TB) in China. TBP is difficult to diagnose. Whether the mononuclear cell/leukocyte (MNC/LEU) ratio in pleural effusion can contribute to accurate TBP diagnosis remains yet unclear.

Objective: To explore the diagnostic value of MNC/LEU ratio in pleural effusion for TBP in China.

Methods: This study was a retrospective case-control study involving 406 patients with pleural effusion of unknown cause who were hospitalized at the Henan Provincial People's Hospital. Using histopathological examination of thoracoscopic pleural biopsy as the gold standard for TBP diagnosis, a final total of 215 subjects were included in this study including 91 cases of TBP and 124 cases of non-TBP. The receiver operating characteristic (ROC) curve of pleural effusion MNC/LEU ratio for TBP diagnosis was plotted and the area under curve (AUC) and the optimal cutoff value were determined. In addition, the sensitivity, specificity and accuracy of the MNC/LEU ratio at the optimal cutoff value for TBP diagnosis were also evaluated.

Results: The MNC/LEU ratio was significantly higher in TB pleural effusion [95.9% (89.7–98.0%)] than in non-TB pleural effusion [77.8% (39.3–93.2%)] (P < 0.001). The AUC was 0.776 (95% CI, 0.714–0.830), and the sensitivity, specificity and accuracy for TBP diagnosis at the 93.7% cutoff value were 64.83%, 79.03%, and 0.730, respectively.

Conclusion: The pleural effusion MNC/LEU ratio may be a new and valuable laboratory indicator for the diagnosis of tuberculous pleurisy in China.

Pleural Tuberculosis: A Febrile Presentation Without Respiratory Symptoms

Tuberculosis (TB) is one of the largest public health crises globally, with pleural TB comprising a large portion of cases. It has a significantly minimal presence within the United States in comparison to the rest of the world. Awareness of its presence and acumen on diagnostics and treatment are essential. Conventional tests are often time consuming, and do not always yield accurate results. We present the case of a patient presenting with fevers but no cough, who eventually found to have large pleural effusion and concluded to have pleural TB without pulmonary parenchymal involvement. He then showed measurable improvement with empiric treatment.

Diagnostic Value of Pleural Effusion Mononuclear Cells Count and Adenosine Deaminase for Tuberculous Pleurisy Patients in China: A Case-Control Study

Background: The diagnostic value of pleural effusion mononuclear cells count for tuberculous pleurisy (TBP) is unclear. We aimed to evaluate the diagnostic value of pleural effusion mononuclear cells count and its combination with adenosine deaminase (ADA) in TBP patients. Methods: We initially analyzed 296 patients with unknown pleural effusion from the Department of Respiratory Medicine at Provincial People's Hospital during January 2014 to February 2018. Ultimately, 100 tuberculous pleurisy (TBP) patients and 105 non-tuberculous pleurisy (non-TBP) patients with pleural effusion were investigated in the current study. Meanwhile, pleural effusion mononuclear cells count and ADA test were performed to evaluate the diagnostic value for TBP. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), positive likelihood ratio (LR+), negative likelihood ratio (LR-), accuracy and area under the receiver operating characteristic (ROC) curve (AUC) of pleural effusion mononuclear cells count only and its combination with ADA for TBP diagnosis were investigated. Results: (i) The best cut-off value of pleural effusion mononuclear cells count for TBP diagnosis was 969.6 × 10⁶/L, with the sensitivity, specificity and accuracy of 76, 57, and 66%, respectively. (ii) Combination of pleural effusion mononuclear cells count and ADA test suggested diagnostic value for TBP. Specifically, serial test showed the sensitivity, specificity, accuracy of 65, 90, 78%, respectively, whereas parallel test revealed the sensitivity, specificity, accuracy of 92, 45, 68%, respectively. The sensitivity of parallel test (92%) was significantly higher than pleural effusion mononuclear cells count alone (76%) (X² = 23.19, p < 0.001). (iii) The area under the ROC of pleural effusion mononuclear cells count and it combined with ADA were 0.66 (95% CI, 0.59-0.72) and 0.83 (95% CI, 0.78-0.89), respectively, with statistically significant difference (Z = 3.46, p < 0.001). Conclusion: This retrospective case-control study demonstrated that pleural effusion mononuclear cells count is relatively useful for TBP diagnosis. Furthermore, the pleural effusion mononuclear cells count in combination with ADA can further improve the diagnostic accuracy of TBP.

Mesothelium and Malignant Mesothelioma

The mesothelium is an epithelial structure derived from the embryonic mesoderm. It plays an important role in the development of a number of different organs, including the heart, lungs, and intestines. In this publication, we discuss aspects of the development of the mesothelium, where mesothelial structures can be found, and review molecular and cellular characteristics associated with the mesothelium. Furthermore, we discuss the involvement of the mesothelium in a number of disease conditions, in particular in the pathogenesis of mesotheliomas with an emphasis on malignant pleural mesothelioma (MPM)—a primary cancer developing in the pleural cavity.

Ultrasound-Guided versus Thoracoscopic Pleural Biopsy for Diagnosing Tuberculous Pleurisy Following Inconclusive Thoracentesis: A Randomized, Controlled Trial

BACKGROUND Traditional diagnostic methods for tuberculosis (TB) cannot be reliably applied to tuberculous pleurisy. Therefore, this prospective, randomized, controlled trial was performed to compare the diagnostic sensitivity and safety of ultrasound-guided cutting-needle pleural biopsy versus thoracoscopic pleural biopsy in patients suspected of tuberculous pleurisy following inconclusive thoracentesis. MATERIAL AND METHODS A total of 196 adult patients with acid-fast bacillus (AFB)-negative exudative pleural effusions clinically suspected of tuberculous pleurisy were recruited. Enrollees were randomized into 2 cohorts: ultrasound-guided cutting-needle pleural biopsy (n=96) or thoracoscopic pleural biopsy (n=96). The overall diagnostic yields, diagnostic sensitivities for tuberculous pleurisy, and post-procedural complications for both cohorts were statistically compared. RESULTS Ultrasound-guided pleural biopsy displayed an overall diagnostic yield of 83%, while thorascopic pleural biopsy displayed a similar overall diagnostic yield of 86% (χ²=1.88, df=1, p=0.17). There were 127 patients conclusively diagnosed with tuberculous pleurisy, resulting in a tuberculous pleurisy prevalence of 65% in this patient population (66% in the ultrasound cohort vs. 63% in the thoracoscopy cohort; p>0.05). Ultrasound-guided pleural biopsy displayed a sensitivity of 82% in detecting tuberculous pleurisy, while thorascopic pleural biopsy displayed a similar sensitivity of 90% (χ²=1.05, df=1, p=0.30). The sensitivities of these 2 modalities did not significantly differ based on the degree of pleural thickening (p>0.05). Post-procedural complications were minor. CONCLUSIONS Ultrasound-guided and thoracoscopic pleural biopsy both display strong (>80%) but statistically similar overall diagnostic yields for diagnosing pleural effusions following inconclusive thoracentesis. Both modalities also display strong (>80%) but statistically similar sensitivities in detecting tuberculous pleurisy.

Imaging manifestations of B-mode ultrasound combined with CT in tuberculous pleuritis patients and the diagnostic value

Clinical diagnostic values of B-mode ultrasound and computed tomography (CT) for tuberculous pleuritis were investigated. A total of 685 patients clinically diagnosed with tuberculous pleuritis in Yantaishan Hospital from January 2012 to August 2016 were selected as study subjects. The patients were examined by B-mode ultrasound and CT. The accuracy of B-mode ultrasound and CT in the diagnosis of tuberculous pleuritis was evaluated and the benefit-cost ratios of the two auxiliary diagnostic methods were compared. According to the imaging diagnostic results of 685 tuberculous pleuritis patients, B-mode ultrasound examinations identified 415 cases with tuberculous pleuritis and the accuracy rate was 60.15%. CT examinations identified 501 cases with the tuberculous pleuritis and the accuracy rate was 70.07%. The combined use of these two methods identified 546 cases with the tuberculous pleuritis and the accuracy rate was significantly increased to 85.99%. B-mode ultrasound imaging findings showed that the lesions of tuberculous pleuritis were localized on the right pleural cavities and the majority of images presented the free type; multiple anechoic areas were seen in the effusion. CT findings indicated obvious free effusion in the pleural cavities, local thickening of the pleural cavities, encapsulated pleural effusion and extensive pleural adhesion, thickening and calcification. Both B-mode ultrasound and CT examinations can be used to accurately diagnose tuberculous pleuritis and the combined diagnosis can significantly improve the accuracy.

Disseminated tuberculosis after pregnancy progressed to paradoxical response to the treatment: report of two cases

Background

Early postpartum women are more likely to develop tuberculosis than nonpregnant women mainly due to immune reconstitution after delivery. Paradoxical response (PR) during antituberculosis treatment also arises via recovery from immunosuppression. However, no study focused on PR during antituberculosis treatment in a postpartum patient has been reported.

Case presentation

We present two sequential cases (Patient 1: 26-year-old; Patient 2: 29-year-old) of postpartum tuberculosis with pulmonary and extrapulmonary lesions (Patient 1: peritonitis; Patient 2: psoas abscess secondary to spondylitis). Both cases progressed to PR (worsening of pre-existing lung infiltrations (Patients 1, 2) and new contralateral effusion (Patient 2)) in a relatively short time after initiation of treatment (Patient 1: 1 week; Patient 2: 3 weeks), suggesting that immune modulations during pregnancy and delivery may contribute to the pathogenesis of both disseminated tuberculosis and its PR. The pulmonary lesions and effusion of both cases gradually improved without change of chemotherapy regimen.

Conclusion

Physicians should recognize PR in tuberculosis patients with postpartum and then evaluate treatment efficacy.

Role of medical thoracoscopy in the treatment of tuberculous pleural effusion

BACKGROUND

Fibrous tuberculous pleural effusion (TPE) represents common disease in tuberculous clinic. Medical thoracoscopy has been used to treat pleural empyema and shown promising outcomes, but data of its use in multiloculated and organized TPE remains limited to know.

METHODS

The study was performed on 430 cases with TPE. The cases were divided into free-flowing, multiloculated effusion and organized effusion group. Each group was subdivided into two or three types of therapeutic approaches: ultrasound guided pigtail catheter, large-bore tube chest drainage and medical thoracoscopy. Patients with multiloculated or organized effusions received streptokinase, introduced into the pleural cavity via chest tubes. The successful effectiveness of the study was defined as duration of chest drainage, time from treatment to discharge days and no further managements.

RESULTS

Patients with organized effusion were older than those with free-flowing effusion and incidence of organized effusion combined with pulmonary tuberculosis (PTB) was higher than those of multiloculated effusion and free-flowing effusion respectively. Positive tuberculosis of pleural fluid culture was higher in organized effusion than that in free-flowing effusion. Sputum positive for acid-fast bacillus (AFB) in organized effusion was higher than that in multiloculated effusion and free-flowing effusion. Medical thoracoscopy showed significant efficacy in the group of multiloculated effusion and organized effusion but free-flowing effusion. No chronic morbidity and mortality related to complications was observed.

CONCLUSIONS

Medical thoracoscopy was a safe and successful method in treating multiloculated and organized TPE.

Adjunctive steroid therapy for managing pulmonary tuberculosis

BACKGROUND

Tuberculosis causes approximately 8.6 million disease episodes and 1.3 million deaths worldwide per year. Although curable with standardized treatment, outcomes for some forms of tuberculosis are improved with adjunctive corticosteroid therapy. Whether corticosteroid therapy would be beneficial in treating people with pulmonary tuberculosis is unclear.

OBJECTIVES

To evaluate whether adjunctive corticosteroid therapy reduces mortality, accelerates clinical recovery or accelerates microbiological recovery in people with pulmonary tuberculosis.

SEARCH METHODS

We identified studies indexed from 1966 up to May 2014 by searching: Cochrane Infectious Diseases Group's trials register, Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE and LILACS using comparative search terms. We handsearched reference lists of all identified studies and previous reviews and contacted relevant researchers, organizations and companies to identify grey literature.

SELECTION CRITERIA

Randomized controlled trials and quasi-randomized control trials of recognized antimicrobial combination regimens and corticosteroid therapy of any dose or duration compared with either no corticosteroid therapy or placebo in people with pulmonary tuberculosis were included.

DATA COLLECTION AND ANALYSIS

At least two investigators independently assessed trial quality and collected data using pre-specified data extraction forms. Findings were reported as narrative or within tables. If appropriate, Mantel-Haenszel meta-analyses models were used to calculate risk ratios.

MAIN RESULTS

We identified 18 trials, including 3816 participants, that met inclusion criteria. When compared to taking placebo or no steroid, corticosteroid use was not shown to to reduce all-cause mortality, or result in higher sputum conversion at 2 months or at 6 months (mortality: RR 0.77, 95%CI 0.51 to 1.15, 3815 participants, 18 studies, low quality evidence; sputum conversion at 2 months RR 1.03, 95%CI 0.97 to 1.09, 2750 participants, 12 studies; at 6 months; RR1.01, 95%CI 1.01, 95%CI 0.98 to 1.04, 2150 participants, 9 studies, both low quality evidence). However, corticosteroid use was found to increase weight gain (data not pooled, eight trials, 1203 participants, low quality evidence), decrease length of hospital stay (data not pooled, three trials, participants 379, very low quality of evidence) and increase clinical improvement within one month (RR 1.16, 95% CI 1.09 to 1.24; five trials, 497 participants, low quality evidence).

AUTHORS' CONCLUSIONS

It is unlikely that adjunctive corticosteroid treatment provides major benefits for people with pulmonary tuberculosis. Short term clinical benefits found did not appear to be maintained in the long term. However, evidence available to date is of low quality. In order to evaluate whether adjunctive corticosteroids reduce mortality, or accelerate clinical or microbiological recovery in people with pulmonary tuberculosis further large randomized control trials sufficiently powered to detect changes in such outcomes are needed.

Clinical peculiarities of tuberculosis

The ongoing spread of tuberculosis (TB) in poor resource countries and the recently increasing incidence in high resource countries lead to the need of updated knowledge for clinicians, particularly for pediatricians. The purpose of this article is to provide an overview on the most important peculiarities of TB in children. Children are less contagious than adults, but the risk of progression to active disease is higher in infants and children as compared to the subsequent ages. Diagnosis of TB in children is more difficult than in adults, because few signs are associated with primary infection, interferon-gamma release assays and tuberculin skin test are less reliable in younger children, M. tuberculosis is more rarely detected in gastric aspirates than in smears in adults and radiological findings are often not specific. Treatment of latent TB is always necessary in young children, whereas it is recommended in older children, as well as in adults, only in particular conditions. Antimycobacterial drugs are generally better tolerated in children as compared to adults, but off-label use of second-line antimycobacterial drugs is increasing, because of spreading of multidrug resistant TB worldwide. Given that TB is a disease which often involves more than one member in a family, a closer collaboration is needed between pediatricians and clinicians who take care of adults.

An intra-abdominal abscess or "rind" as a consequence of peritoneal dialysis-associated pseudomonas peritonitis

Background: Abdominal CT imaging has defined characteristics of two pathological entities specific to peritoneal dialysis patients. Both are associated with serious peritoneal complications. One is comprised of ascites accompanied by septation and loculated fluid pockets as a complication of bacterial peritonitis. The other is the syndrome of encapsulating peritoneal sclerosis. We present the evolution of a single, thick-walled fluid collection as a consequence of relapsing Pseudomonas aeruginosa peritonitis. The entity had distinctive features differing from either of the two previously described entities, and to our knowledge, has not been described previously. Our patient’s radiological evolution resembled the formation of a pleural or peritoneal “rind.” Conclusion: Peritonitis, as a result of Pseudomonas aeruginosa, may lead to “rind” formation as described with empyemas and is distinct from previously described intra-abdominal pathologies in peritoneal dialysis patients.

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.