Performance of adenosine deaminase in synovial fluid for the diagnosis of tuberculous arthritis: A systematic review and meta-analysis / Rendimiento de la adenosina desaminasa en el líquido sinovial para el diagnóstico de la artritis tuberculosa: una revisión sistemática y metaanálisis

Objectives: Adenosine deaminase (ADA) activity has shown good performance in diagnosing pleural, peritoneal, and meningeal tuberculosis. This meta-analysis aimed to evaluate the performance of measuring ADA activity in synovial fluid for the early diagnosis of joint tuberculosis. Methods: We searched published information in MEDLINE, Embase, Cochrane Library, Web of Science, and MedRxiv databases, as well as unpublished information in the American College of Rheumatology and European League Against Rheumatism for conference abstracts (2012–2021). We also scanned the reference lists of articles. Two reviewers independently applied the criteria for selection, assessed quality, and extracted data (PROSPERO number CRD42021284472). Results: Seven independent studies (N=305 subjects) that compared ADA activity in synovial fluid with a composite reference diagnostic method for tuberculosis were included. Overall, the risk of bias was judged low. Studies were classified as high quality (n=3; 148 subjects) and low quality (n=4; 157 subjects). Pooled sensitivity and specificity of ADA activity was 94% (95% confidence interval [CI], 0.89–98; I2=23%) and 88% (95% CI, 83–92; I2=83%), respectively. The random-effects model for pooled diagnostic Odds ratio was 67.1 (95%CI, 20.3–222.2; I2=30%). The receiver operating characteristic curve area was 0.96 (95% CI, 0.92–0.99). Meta-regression did not identify the quality of the study, country of publication, or the type of assay as a source of heterogeneity. Conclusions: Measuring ADA activity in synovial fluid demonstrates good performance for the early diagnosis of joint tuberculosis.(AU)

Objetivos: La actividad de la adenosina desaminasa (ADA) ha mostrado un buen desempeño en el diagnóstico de la tuberculosis pleural, peritoneal y meníngea. Este metaanálisis tuvo como objetivo evaluar el rendimiento de la medición de la actividad de la ADA en el líquido sinovial para el diagnóstico precoz de la tuberculosis articular. Métodos: Se realizaron búsquedas de resúmenes de congresos en la información publicada en las bases de datos MEDLINE, Embase, Cochrane Library, Web of Science y MedRxiv, así como en información no publicada en el American College of Rheumatology y la European League Against Rheumatism (2012-2021). También se escanearon las listas de referencias de los artículos. Dos revisores aplicaron de forma independiente los criterios de selección, evaluaron la calidad y extrajeron los datos (número PROSPERO CRD42021284472). Resultados: Se incluyeron siete estudios independientes (n=305 sujetos) que compararon la actividad de la ADA en el líquido sinovial con un método diagnóstico compuesto de referencia para la tuberculosis. En general, el riesgo de sesgo se consideró bajo. Los estudios se clasificaron como de alta calidad (n=3; 148 sujetos) y de baja calidad (n=4; 157 sujetos). La sensibilidad y la especificidad agrupadas de la actividad de la ADA fueron del 94% (intervalo de confianza [IC] del 95%: 0,89-98; I2=23%) y del 88% (IC95%: 83-92; I2=83%), respectivamente. El modelo de efectos aleatorios para el odds ratio diagnóstico agrupado fue de 67,1 (IC95%: 20,3-222,2; I2=30%). El área de la curva característica de operación del receptor fue de 0,96 (IC95%: 0,92-0,99). La metarregresión no identificó la calidad del estudio, el país de publicación o el tipo de ensayo como fuente de heterogeneidad.Conclusiones: La medición de la actividad de ADA en el líquido sinovial demuestra un buen rendimiento para el diagnóstico precoz de la tuberculosis articular.(AU)

Tuberculous pleuritis: clinical presentations and diagnostic challenges.

PURPOSE OF REVIEW: Tuberculous pleuritis (TBP) is one of the most common types of extrapulmonary tuberculosis. We highlight the latest epidemiology of TBP, the heterogeneity of its presentation and the performance of different diagnostic strategies. RECENT FINDINGS: There are differential trends in the incidences of TBP worldwide. Its incidence increased in China but decreased in the United States in the past decade. The presentation of TBP is heterogeneous regarding clinical symptoms, radiological findings and pleural fluid analysis results. Conventional microbiological tests have low sensitivities to diagnose TBP. Recent research focused on various diagnostic tools with better yield. The sensitivity of nucleic acid amplification tests (NAAT) in pleural fluid, including the latest generation of PCR and sequencing-based techniques for detecting tuberculosis, remains suboptimal. Various pleural fluid biomarkers have been explored, but there is a lack of consensus on their clinical utility and cutoff levels. SUMMARY: The heterogeneity of clinical presentation poses obstacles to diagnosing TBP. Further development of diagnostic tools, including more robust NAAT and biomarkers with additional validation, is needed before incorporation into routine clinical practice.

Diagnostic accuracy of Lipoarabinomannan detection by lateral flow assay in pleural tuberculosis.

BACKGROUND: Lipoarabinomannan (LAM) antigen serves as an attractive biomarker to diagnose Tuberculosis (TB). Given the limitations of current diagnostic modalities for Pleural TB, current study evaluated LAM's potential to serve as a point-of-care test to diagnose pleural TB. METHODS: A cross sectional, diagnostic accuracy study was conducted during February to November 2021 in a tertiary care hospital in India. LAM antigen detection was performed on pleural fluid as well as early morning urine specimen of suspected pleural TB patients by "Alere/ Abott Determine TB LAM" lateral flow assay (LAM-LFA). The results were compared to microbiological reference standards/MRS (Mycobacterial culture or NAAT) and Composite reference standards/CRS (MRS plus Clinico-radiological diagnosis). RESULTS: A total of 170 subjects were included in the analysis, including 26 with Definite TB, 22 with Probable TB, and 122 with No TB. Compared to MRS and CRS, the sensitivity (61.54% & 45.83%) and positive predictive value (PPV) (57.14 & 78.57%) of Pleural LAM-LFA testing were found to be suboptimal, whereas the specificity (91.67% & 95.08%) and negative predictive value (NPV) (92.96% & 81.69%) of the assay were found to be good. Urinary LAM-LFA performed even worse than pleural LAM-LFA, except for its higher specificity against MRS and CRS (97.2% and 98.3%, respectively). Specificity and PPV of pleural LAM detection increased to 100% when analysed in a subgroup of patients with elevated ADA levels (receiver operating curve analysis-derived cut off value > 40 IU/ml). CONCLUSION: Detection of LAM antigen by LFA directly from pleural fluid was found to be a useful test to predict absence of the disease if the test is negative rather than using as a POCT for diagnosis.

Tuberculosis pleural y endocarditis como complicaciones de origen multifactorial en granulomatosis con poliangítis. Reporte de caso clínico / Pleural tuberculosis and endocarditis as complications of multifactorial origin in granulomatosis with polyangiitis: Clinical case report

Se presenta el caso de femenino de 36 años con antecedentes de granulomatosis con poliangítis; enfermedad renal crónica e hipertensión arterial sistémica. Debutó con disnea, debilidad y hemoptisis, se sospechó en neumonía atípica, descartándose, persistiendo con taquipnea, taquicardia, dolor torácico. Se inició protocolo para tuberculosis pulmonar con muestras de esputo negativas, hemocultivo positivo para S. haemolyticus, tomografía de tórax con neumotórax izquierdo y derrame pleural ipsilateral, se obtuvo líquido pleural tipo exudado, tinción ácido alcohol-resistente y reacción en cadena de la polimerasa (PCR) para M. tuberculosis negativas; se realizó ecocardiograma de rastreo por soplo de nueva aparición, reportando vegetación valvular, concluyendo diagnóstico de tuberculosis pleural y endocarditis como complicaciones de origen multifactorial asociado a inmunosupresión en granulomatosis con poliangítis.(AU)

We present the case of a 36-year-old woman with a history of granulomatosis with polyangiitis, chronic kidney disease, and systemic arterial hypertension. Debut with dyspnea, weakness, and hemoptysis, she was suspected in atypical pneumonia, discarded, persisting with tachypnea, tachycardia, and chest pain. The protocol for pulmonary tuberculosis was started with negative sputum samples, positive blood culture for Staphylococcus haemolyticus, chest tomography with left pneumothorax and ipsilateral pleural effusion, exudate-type pleural fluid was obtained, acid-fast staining, negative PCR for Mycobacterium tuberculosis. A follow-up echocardiogram was performed due to a new murmur, reporting valvular vegetation, concluding a diagnosis of pleural tuberculosis and endocarditis as complications of multifactorial origin associated with immunosuppression in granulomatosis with polyangiitis.(AU)

Features which discriminate between tuberculosis and haematologic malignancy as the cause of pleural effusions with high adenosine deaminase.

BACKGROUND: Adenosine deaminase (ADA) is a useful biomarker for the diagnosis of tuberculous pleurisy (TBP). However, pleural effusions with high ADA can also be caused by other diseases, particularly hematologic malignant pleural effusion (hMPE). This study aimed to investigate the features that could differentiate TBP and hMPE in patients with pleural effusion ADA ≥ 40 IU/L. METHODS: This was a retrospective observational study of patients with pleural effusion ADA ≥ 40 IU/L, conducted at a Korean tertiary referral hospital with an intermediate tuberculosis burden between January 2010 and December 2017. Multivariable logistic regression analyses were performed to investigate the features associated with TBP and hMPE, respectively. RESULTS: Among 1134 patients with ADA ≥ 40 IU/L, 375 (33.1%) and 85 (7.5%) were diagnosed with TBP and hMPE, respectively. TBP and hMPE accounted for 59% (257/433) and 6% (27/433) in patients with ADA between 70 and 150 IU/L, respectively. However, in patients with ADA ≥ 150 IU/L, they accounted for 7% (9/123) and 19% (23/123), respectively. When ADA between 40 and 70 IU/L was the reference category, ADA between 70 and 150 IU/L was independently associated with TBP (adjusted odds ratio [aOR], 3.11; 95% confidence interval [CI], 1.95-4.95; P < 0.001). ADA ≥ 150 IU/L was negatively associated with TBP (aOR, 0.35; 95% CI, 0.14-0.90; P = 0.029) and positively associated with hMPE (aOR, 13.21; 95% CI, 5.67-30.79; P < 0.001). In addition, TBP was independently associated with lymphocytes ≥ 35% and a lactate dehydrogenase (LD)/ADA ratio < 18 in pleural effusion. hMPE was independently associated with pleural polymorphonuclear neutrophils < 50%, thrombocytopenia, and higher serum LD. A combination of lymphocytes ≥ 35%, LD/ADA < 18, and ADA < 150 IU/L demonstrated a sensitivity of 0.824 and specificity of 0.937 for predicting TBP. CONCLUSION: In patients with very high levels of pleural effusion ADA, hMPE should be considered. Several features in pleural effusion and serum may help to more effectively differentiate TBP from hMPE.

Accidental Detection of Tuberculous Empyema at Health Check-Up.

BACKGROUND: Patients with tuberculous empyema (TE) can have a serious impact on lung function as their disease progresses, and, if left untreated, can cause damage to other parts of the body such as the thorax and spine, causing pain and inconvenience to the patient. Early diagnosis and the search for appropriate treatment are key to improving the survival rate of the disease. METHODS: We report a case of a young patient with an unexpected finding of right pleural effusion on physical examination, who was eventually diagnosed with TE using next-generation sequencing of pleural tissue. We analyzed the literature to improve clinicians' understanding of TE and how to properly diagnose and treat the disease. RESULTS: Laboratory results of the pleural effusion suggested a possible Mycobacterium tuberculosis infection, but pathogen-related tests were negative, and the diagnosis was eventually successfully confirmed by thoracoscopic pleural biopsy. CONCLUSIONS: The diagnosis of TE should be considered in young patients with pleural thickening of the empyema. Adenosine deaminase may provide diagnostic direction in patients with unexplained thorax abscess. Pleural biopsy, although an invasive procedure, is an essential diagnostic tool in some cases.

Interleukin-6 and -27 as potential novel biomarkers for human pleural tuberculosis regardless of the immunological status.

Tuberculosis (TB) is the leading cause of pleural exudative effusions. Inflammatory markers, such as IFNγ and ADA, have been used as proxies for its diagnosis. We evaluated ex vivo levels of several cytokines in 83 pleural effusion specimens from patients with TB (including 10 with HIV co-infection) and 26 patients with other pleuritis using multiplex and ELISA assays. IL-6 and IL-27 levels were higher (p ≤ 0.04) in TB patients, regardless of the HIV status and the approach. IL-2, IL-4, IL-8, IFNγ, TNF and G-CSF showed variable results depending on the assay. This warranty these markers to be further validated.

Diagnostic and comparative performance for the prediction of tuberculous pleural effusion using machine learning algorithms.

OBJECTIVE: Early diagnosis and differential diagnosis of tuberculous pleural effusion (TPE) remains challenging and is critical to the patients' prognosis. The present study aimed to develop nine machine learning (ML) algorithms for early diagnosis of TPE and compare their performance. METHODS: A total of 1435 untreated patients with pleural effusions (PEs) were retrospectively included and divided into the training set (80%) and the test set (20%). The demographic and laboratory variables were collected, preprocessed, and analyzed to select features, which were fed into nine ML algorithms to develop an optimal diagnostic model for TPE. The proposed model was validated by an independently external data. The decision curve analysis (DCA) and the SHapley Additive exPlanations (SHAP) were also applied. RESULTS: Support vector machine (SVM) was the best model in discriminating TPE from non-TPE, with a balanced accuracy of 87.7%, precision of 85.3%, area under the curve (AUC) of 0.914, sensitivity of 94.7%, specificity of 80.7%, and F1-score of 86.0% among the nine ML algorithms. The excellent diagnostic performance was also validated by the external data (a balanced accuracy of 87.7%, precision of 85.2%, and AUC of 0.898). Neural network (NN) and K-nearest neighbor (KNN) had better net benefits in clinical usefulness. Besides, PE adenosine deaminase (ADA), PE carcinoembryonic antigen (CEA), and serum CYFRA21-1 were identified as the top three important features for diagnosing TPE. CONCLUSIONS: This study developed and validated a SVM model for the early diagnosis of TPE, which might help clinicians provide better diagnosis and treatment for TPE patients.

Diagnostic flowchart for tuberculous pleurisy, pleural infection, and malignant pleural effusion.

BACKGROUND: Several markers for the diagnosis of pleural effusion have been reported; however, a comprehensive evaluation using those markers has not been performed. Therefore, this study aimed to develop a diagnostic flowchart for tuberculous pleurisy, pleural infection, malignant pleural effusion, and other diseases by using these markers. METHODS: We retrospectively collected data from 174 patients with tuberculous pleurisy, 215 patients with pleural infection other than tuberculous pleurisy, 360 patients with malignant pleural effusion, and 209 patients with other diseases at Fukujuji Hospital from January 2012 to October 2022. The diagnostic flowchart for four diseases was developed by using several previously reported markers. RESULTS: The flowchart was developed by including seven markers: pleural ADA ≥40 IU/L, pleural fluid LDH <825 IU/L, pleural fluid ADA/TP < 14, neutrophil predominance or cell degeneration, peripheral blood WBC ≥9200/µL or serum CRP ≥12 mg/dL, pleural amylase ≥75 U/L, and the presence of pneumothorax according to the algorithm of a decision tree. The accuracy ratio of the flowchart was 71.7 % for the diagnosis of the four diseases, with 79.3 % sensitivity and 75.4 % positive predictive value (PPV) for tuberculosis pleurisy, 75.8 % sensitivity and 83.2 % PPV for pleural infection, 88.6 % sensitivity and 68.8 % PPV for malignant pleural effusion, and 33.0 % sensitivity and 60.0 % PPV for other diseases in the flowchart. The misdiagnosis ratios were 4.6 % for tuberculosis pleurisy, 6.8 % for pleural infection, and 8.3 % for malignant pleural effusion. CONCLUSION: This study developed a useful diagnostic flowchart for tuberculous pleurisy, pleural infection, malignant pleural effusion, and other diseases.

Diagnosis of pleural tuberculosis by multi-targeted loop-mediated isothermal amplification assay based on SYBR Green I reaction: comparison with GeneXpert® MTB/RIF assay.

BACKGROUND: Diagnosis of pleural tuberculosis (TB) is tedious owing to its close resemblance with malignant pleural effusion and sparse bacterial load in clinical specimens. There is an immediate need to design a rapid and dependable diagnostic test to prevent unnecessary morbidity/mortality. RESEARCH DESIGN AND METHODS: A multi-targeted loop-mediated isothermal amplification (MT-LAMP) was deliberated using mpt64 and IS6110 to diagnose pleural TB within pleural fluids/biopsies. MT-LAMP products were analyzed by gel-based and visual detection methods, viz. SYBR Green I, SYBR Green I+deoxyuridine triphosphate uracil-N-glycosylase (dUTP-UNG), and dry methyl green reactions. RESULTS: In a pilot study, while assessing pleural TB/non-TB control subjects (n = 40), both SYBR Green I+dUTP-UNG/gel-based MT-LAMP assays exhibited better sensitivity/specificity than SYBR Green I and dry methyl green MT-LAMP. Since it is facile to work with SYBR Green I+dUTP-UNG than gel-based MT-LAMP, we validated the performance of SYBR Green I+dUTP-UNG in a higher number of specimens (n = 97), which revealed somewhat higher sensitivity (85.2 vs. 81.5%) and specificity (97.7 vs. 90.7%) than SYBR Green I MT-LAMP. Furthermore, the sensitivity attained by SYBR Green I+dUTP-UNG MT-LAMP was significantly higher (p < 0.001) than GeneXpert. CONCLUSIONS: Our SYBR Green I+dUTP-UNG MT-LAMP is a simple and reliable method to diagnose pleural TB, which may translate into a point-of-care test.

Diagnostic accuracy and microbial profiles of tuberculous pleurisy: a comparative study of metagenomic next generation sequencing and GeneXpert Mycobacterium tuberculosis.

Introduction: There is a clinical challenge in diagnosing tuberculous pleurisy accurately and promptly, highlighting the urgent need for a rapid and sensitive diagnostic method. This study aimed to evaluate the diagnostic accuracy of metagenomic next-generation sequencing (mNGS) and GeneXpert Mycobacterium tuberculosis (MTB) for identifying tuberculous pleurisy and analyzing the microbial profiles of both tuberculous and non-tuberculous pleural effusions. Methods: The study enrolled 31 patients with suspected tuberculous pleurisy, of which 15 were confirmed to have tuberculous pleurisy and subsequently allocated to the tuberculous pleurisy group (TP group), while the remaining 16 individuals were assigned to the non-tuberculous pleurisy group (NTP group). mNGS and GeneXpert MTB were performed on pleural effusion samples, and the diagnostic accuracy of both tests was compared. We employed established formulas to compute crucial indicators, including sensitivity, specificity, missed diagnosis rate, misdiagnosed rate, positive predictive value (PPV), and negative predictive value (NPV). Results: The results showed that both tests had high specificity (100%) and positive predictive value (100%) for detecting tuberculous pleurisy, along with comparable sensitivity (46.67% for mNGS and 40.0% for GeneXpert MTB). Further analysis of the combined efficacy of mNGS and GeneXpert MTB showed that the combined test had a sensitivity of 66.67% and a specificity of 100%. mNGS analysis revealed that MTB was detected in 7 out of 15 patients with tuberculous pleural effusions, while non-tuberculous pleural effusions were associated with a diverse range of microbial genera and species. The most frequently detected genera at the microbial genus level in the NTP group were Microbacterium spp. (6/16), Prevotella spp. (5/16), and Campylobacter spp. (5/16). Discussion: These findings suggest that mNGS and GeneXpert MTB are useful diagnostic tools for identifying patients with tuberculous pleurisy, and mNGS can provide valuable insights into the microbial profiles of both tuberculous and non-tuberculous pleural effusions.

Biomarkers for distinguishing tuberculous pleural effusion from non-tuberculosis effusion: a retrospective study.

BACKGROUND: Pleural effusion (PE) is a common clinical feature that presents a diagnostic challenge for clinicians. In this retrospective study, we aimed to assess the biomarkers, ratios, and multiple indicators in serum and Pleural effusion for the differential diagnosis of tuberculous pleural effusion (TPE) from non-tuberculosis effusion (non-TPE). METHODS: The participants, who were divided into two groups: TPE and non-TPE (MPE and PPE), from Ningbo First Hospital, were incorporated in this study. The clinical and laboratory features were collected and analyzed using logistic regression analysis. Twelve biomarkers and their ratios in serum and PE were investigated for TPE versus non-TPE. Additionally, the value of multiple indicators for joint diagnosis was estimated. RESULTS: Biomarkers and ratios showed good diagnostic performance. The five variables including Serum ADA, IGRA, Effusion ADA, Effusion ADA/Serum ADA and Effusion LDH/Effusion ADA were identified as valuable parameters for differential diagnosis of TPE from non-TPE. The combined diagnosis of the five indexes yielded the highest diagnostic accuracy for TPE with an AUC (0.919), sensitivity (90.30%), and specificity (94.50%). CONCLUSIONS: The biomarkers and ratios demonstrated strong diagnostic performance, and the utilization of multiple indicators for joint diagnosis can improve the diagnostic efficacy of tuberculous pleurisy.

Conditional diagnostic accuracy according to inflammation status and age for diagnosing tuberculous effusion.

BACKGROUND: Tuberculous effusion varies from lymphocyte-dominant to neutrophilic effusion according to inflammation status. The criteria of adenosine deaminase (ADA) and lymphocyte/neutrophil (L/N) ratio have yet not been evaluated across different disease conditions. METHODS: Patients who conducted pleural fluid analysis from 2009 to 2019 at Asan Medical Center were included. Criteria (ADA of 50 and L/N ratio of 0.75) were evaluated by quantile subgroups according to age, C-reactive protein (CRP), white blood cell (WBC), and lactate dehydrogenase (LD) by the Monte Carlo simulation method to diagnose tuberculosis. The model for the ADA and L/N ratio was evaluated by AUROC. RESULTS: Among the 2,918 reviewed cases, 2034 were included with 229 (11.26%) tuberculosis cases. The mean baseline ADA AUROC was 0.88 across all patients. Increased CRP and WBC showed high proportions of neutrophilic tuberculous effusion, with low sensitivity of approximately 45% and 33% in the fifth WBC and CRP groups, respectively. The AUROC of the models decreased with the increase in WBC and CRP groups (ADA model: 0.69 [the top quantile WBC group], 0.74 [the top quantile CRP group]). The AUROC of the models did not show a trend according to the increase in LD and age. CONCLUSION: Inflammatory status affects the diagnostic metrics for tuberculous effusion due to the progression of tuberculous effusion. Clinicians should consider the low accuracy of tuberculous effusion criteria in high-inflammatory conditions when diagnosing tuberculosis.

Diagnostic Value of CD25, CD69, and CD134 on Tuberculosis-Specific Antigen-Stimulated CD4+ T Cells for Tuberculous Pleurisy.

Rapid and accurate methods for the diagnosis of tuberculous pleurisy (TP) are urgently needed. Activation markers of tuberculosis (TB)-reactive T cells are considered promising for the diagnosis of active TB (ATB). Different activation indexes may play different roles in the progression of TB, but there are few reports on T cell activation indicators, except for HLA-DR. Hence, we evaluated the expression of early (CD25 and CD69) and late (CD134) activation markers on TB antigen-stimulated CD4+ T cells in populations with different TB infection status and investigated their diagnostic value for ATB, particularly, for TP. Moreover, we compared the differences in the diagnostic efficacy among the indexes from peripheral blood (PB) and pleural fluid (PF) for TP. The expression of each activation marker was significantly increased in TB-infected populations (patients with ATB and latent TB infection vs. healthy individuals; patients with TP vs. non-TP) and was significantly higher in the PF than in the PB of patients with TP. The diagnostic performance of the coexpressed activation markers was superior to that of single expression markers in the differential diagnosis of ATB and non-TB, with CD25+CD134+ showing the best diagnostic efficiency (AUC: 0.93, 95% CI, 0.87-0.99; sensitivity: 86.7%, 95% CI, 72.5%-94.5%; and specificity: 94.0%, 95% CI, 82.5%-98.4%). Except for TB-IGRA, the activation indexes were more accurate than conventional laboratory methods for ATB diagnosis. In addition, the expression of CD25+CD134+ in PB and PF was the best values for differential diagnosis of TP and NTP, with AUCs of 0.87 (95% CI, 0.77-0.96) and 0.95 (95% CI, 0.90-1.00), respectively. Our study provides information on the diagnostic value of different activation markers for TB and shows that the expression of CD25+CD134+ on CD4+ T cells in PF can serve as a potential marker for TP diagnosis.

Simultaneous diagnosis of tuberculous pleurisy and malignant pleural effusion using metagenomic next-generation sequencing (mNGS).

BACKGROUND: Metagenomic next-generation sequencing (mNGS) has become a powerful tool for pathogen detection, but the value of human sequencing reads generated from it is underestimated. METHODS: A total of 138 patients with pleural effusion (PE) were diagnosed with tuberculous pleurisy (TBP, N = 82), malignant pleural effusion (MPE, N = 35), or non-TB infection (N = 21), whose PE samples all underwent mNGS analysis. Clinical TB tests including culture, Acid-Fast Bacillus (AFB) test, Xpert, and T-SPOT, were performed. To utilize mNGS for MPE identification, 25 non-MPE samples (20 TBP and 5 non-TB infection) were randomly selected to set human chromosome copy number baseline and generalized linear modeling was performed using copy number variant (CNV) features of the rest 113 samples (35 MPE and 78 non-MPE). RESULTS: The performance of TB detection was compared among five methods. T-SPOT demonstrated the highest sensitivity (61% vs. culture 32%, AFB 12%, Xpert 35%, and mNGS 49%) but with the highest false-positive rate (10%) as well. In contrast, mNGS was able to detect TB-genome in nearly half (40/82) of the PE samples from TBP subgroup, with 100% specificity. To evaluate the performance of using CNV features of the human genome for MPE prediction, we performed the leave-one-out cross-validation (LOOCV) in the subcohort excluding the 25 non-MPE samples for setting copy number standards, which demonstrated 54.1% sensitivity, 80.8% specificity, 71.7% accuracy, and an AUC of 0.851. CONCLUSION: In summary, we exploited the value of human and non-human sequencing reads generated from mNGS, which showed promising ability in simultaneously detecting TBP and MPE.

Evaluation of Mycobacterium tuberculosis derived cell-free DNA using pleural fluid and paired plasma samples for the diagnosis of pleural tuberculosis.

Pleural tuberculosis (pTB) is a grave clinical challenge. A novel cell-free M. tuberculosis DNA (cfM.tb-DNA) probe-based-qPCR assay was developed for the diagnosis of pTB. Total cell-free DNA was extracted from pleural fluid (PF) and paired plasma samples and cfM.tb-DNA was quantified by probe-based qPCR targeting devR (109-bp) gene of M. tuberculosis in patients with pleural effusion. Patient categorization was done using 'Composite-Reference-Standard' formulated for the study. Assay cut-offs were determined from samples in the 'Development set' (n = 17; 'Definite & Probable' pTB; n = 9 and 'Non-TB'; n = 8) by ROC-curve analysis and applied to 'Validation set' (n = 112; 'Definite' pTB; n = 8, 'Probable' pTB; n = 34, 'Possible' pTB; n = 28 and 'Non-TB'; n = 42). cfM.tb-DNA qPCR had a sensitivity of 62.5% (95%CI; 24.4,91.4) in 'Definite' pTB category and 59.5% (95%CI; 43.2,74.3) in 'Definite & Probable' pTB category with 95.2% (95%CI; 83.8,99.4) specificity using PF. In plasma (n = 85), the assay had a sub-optimal sensitivity of 7.6% (95%CI; 0.95,25.1) with 88.2% (95%CI; 72.5,96.7) specificity in 'Definite & Probable' pTB group. Xpert MTB/RIF assay detected only six-samples in the 'Validation set'. Logistic regression analysis indicated that PF-cfM.tb-DNA qPCR provided incremental advantage over existing pTB diagnostic algorithms. To the best of our knowledge, this is the first report describing the utility of cfM.tb-DNA for pTB diagnosis in India.

Brucella pleuritis misdiagnosed as tuberculous pleuritis: a case report.

Pleurisy and pleural effusion caused by Brucella infection are rare. However, clinicians lack an understanding of these possibilities, and the underlying disorder is easy to misdiagnose. We report a 52-year-old male farmer who was admitted to hospital with a fever, chest pain, and shortness of breath. Closed chest drainage was performed by thoracocentesis, and the concentration of adenosine deaminase (ADA) in the pleural fluid was >45 U/L. Mononuclear cells in the pleural fluid accounted for 90% of the cells, and pathology indicated a large number of lymphocytes. The clinical diagnosis was tuberculosis with tuberculous pleurisy. However, subsequent pleural fluid culture results did not support tuberculous pleurisy. The results of pleural fluid culture indicated Brucella, and the results of Brucella tiger red plate agglutination indicated a titer of 1:400 (+++). The final diagnosis was brucellosis with pneumonia and pleurisy. After 12 weeks of oral treatment, the patient underwent follow-up chest radiographs. Radiography indicated complete resolution of the hydrothorax and pneumonia, and the patient reported no discomfort. The short-term curative effect was excellent. Pleurisy associated with brucellosis should be considered a differential for pleurisy in regions where brucellosis is endemic, to minimize the risk of misdiagnosis.

Development and validation of a prediction model to assess the probability of tuberculous pleural effusion in patients with unexplained pleural effusion.

Differentiating tuberculous pleural effusion (TPE) from non-tuberculosis pleural effusion remains a challenge in clinical practice. This study aimed to develop and externally validate a novel prediction model using the peripheral blood tuberculous infection of T cells spot test (T-SPOT.TB) to assess the probability of TPE in patients with unexplained pleural effusion. Patients with pleural effusion and confirmed etiology were included in this study. A retrospective derivation population was used to develop and internally validate the predictive model. Clinical, radiological, and laboratory features were collected, and important predictors were selected using the least absolute shrinkage and selection operator. The prediction model, presented as a web calculator, was developed using multivariable logistic regression. The predictive performance of the model was evaluated for discrimination and calibration and verified in an independent validation population. The developed prediction model included age, positive T-SPOT.TB result, logarithm of the ratio of mononuclear cells to multiple nuclear cells in pleural effusion (lnRMMPE), and adenosine deaminase in pleural effusion ≥ 40 U/L. The model demonstrated good discrimination [with area under the curve of 0.837 and 0.903, respectively] and calibration (with a Brier score of 0.159 and 0.119, respectively) in both the derivation population and the validation population. Using a cutoff value of 60%, the sensitivity and specificity for identifying TPE were 70% and 88%, respectively, in the derivation population, and 77% and 92%, respectively, in the validation population. A novel predictive model based on T-SPOT.TB was developed and externally validated, demonstrating good diagnostic performance in identifying TPE.

Characteristics of pleural effusion due to paradoxical response in patients with pulmonary tuberculosis.

BACKGROUND: Patients with pulmonary tuberculosis may present with deterioration of pleural effusion during anti-tuberculosis therapy, referred to as a paradoxical response (PR), with some patients requiring additional intervention. However, PR may be confused with other differential diagnoses, and the predictive factors for recommending additional therapies are unknown. Therefore, this study aimed to reveal useful information for the diagnosis and intervention of PR. METHODS: Data from human immunodeficiency virus-negative patients with tuberculous pleurisy (n = 210), including 184 patients with pre-existing pleural effusion and 26 patients with PR at Fukujuji Hospital, were retrospectively collected from January 2012 to December 2022 and compared. Furthermore, patients with PR were divided into the intervention group (n = 9) and the no intervention group (n = 17) and were compared. RESULTS: Patients in the PR group had lower pleural lactate dehydrogenase (LDH) (median 177 IU/L vs. 383 IU/L, p < 0.001) and higher pleural glucose (median 122 mg/dL vs. 93 mg/dL, p < 0.001) levels than those in the preexisting pleural effusion group. Other pleural fluid data were not significantly different. Patients in the intervention group had a shorter duration from the initiation of anti-tuberculosis therapy to the development of PR than patients in the no intervention group (median 19.0 days [interquartile range (IQR): 18.0-22.0] vs. median 37.0 days [IQR: 28.0-58.0], p = 0.012). CONCLUSION: This study demonstrates that, apart from lower pleural LDH and elevated pleural glucose levels, PR presents with similar features to preexisting pleural effusion and that patients who develop PR faster tend to require intervention.

Paraffin-embedded Sample Test Promotes the Diagnosis of Tuberculous Pleurisy.

Context: Tuberculous pleurisy (TP) is the most common manifestation of extrapulmonary tuberculosis and the most frequent cause of pleural effusion (PE). Clinicians make a definitive diagnosis of TP based on the isolation of the mycobacterium tuberculosis (MTB) from PE or a pleural biopsy. Since the currently available tests for TP all have limitations in making a definitive diagnosis, clinicians urgently need new diagnostic tests. Objective: The study intended to compare the value in clinically diagnosing TP of the paraffin-embedded sample test (PEST), using pleural-effusion samples; an adenosine deaminase assay (ADA) using pleural fluid; and the T cell enzyme-linked immunospot test (T-SPOT), using peripheral-blood. Design: The research team performed a retrospective observational study. Setting: The study took place at the Sir Run Run Hospital, Nanjing Medical University in Nanjing, Jiangsu, China. Participants: Participants were 37 patients with suspected TP who had been admitted to the hospital between September 2018 and December 2022. Outcome Measures: The research team assessed the diagnostic performance of PEST, ADA, and T-SPOT in the TP group, calculating the positive rate, sensitivity, specificity, negative predictive value (NPV), and positive predictive value (PPV) of the tests. Results: Among the 37 participants, the testing confirmed that 24 had TP (64.86%), with 13 not having TP (35.14%). The PEST test produced a sensitivity of 83.3% for TP, with 20 out of 24 participants in the TP group testing positive (95% CI: 61.8 to 94.5), which was superior to the ADA, with only 9 out of the 24 participants (37.5%) in the TP group testing positive (95% CI: 19.6 to 59.2), with P < .001. Conclusions: The PEST test possesses a high diagnostic value, and clinicians can use it as a time-saving, noninvasive, and highly sensitive method for TP diagnosis. It can be adjunct method to the currently used tests for diagnosing TP. A combination of several detection methods could promote effective treatment.