Diagnosis of tuberculous pleurisy with combination of adenosine deaminase and interferon-γ immunospot assay in a tuberculosis-endemic population: A prospective cohort study

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.

Application of Adenosine Deaminase and γ-Interferon Release Assay in Pleural Fluid for the Diagnosis of Tuberculous Pleural Effusion in Patients Over 40 Years Old

Background

In patients with tuberculous pleural effusion (TPE) of various ages, the diagnostic accuracy of pleural biomarkers varies, and there are insufficient studies specifically in different age groups. Therefore, we investigated the adenosine deaminase cut-off value and its combination with the gamma interferon release assay for the diagnosis of TPE among patients aged ≥40 years.

Methods

A retrospective analysis of 198 patients who underwent medical thoracoscopy and were admitted to the hospital between 2015 and 2020 with exudative pleural effusion and either fever, night sweats, fatigue, cough, or other clinical manifestations was performed. The medical thoracoscopy, ADA, and T-SPOT results were analysed in the pleural fluid. The patients were divided into groups based on age: 18-39, 40-59, and 60-87.

Results

The best cut-off values of ADA were 29.5, 31.5 and 19.5 U/L, respectively, for the aged 18-39, aged 40-87 and aged 60-87 groups. The accuracy of 31.5 U/L was higher than 40 U/L for aged ≥40 years (86 vs 83%). The ADA diagnostic accuracy was higher than that of people under 40 years (83 vs 77%) when cut-off value of ADA was 40 U/L, but the IGRA accuracy was lower than that of people under 40 (87 vs 91%). The sensitivity of ADA or IGRA detection in patients over 40 years was 99%, and the specificity was 78%. The ADA specificity combined with IGRA for TPE was the highest (100%) in the ≥40 age group, and the sensitivity was 69%.

Conclusion

Our study revealed the best cut-off values of ADA for TBE in different age groups. Combining ADA and IGRA in pleural fluid improves the detection rate of TPE in patients over 40 years of age with exudative pleural effusion. ADA combined with IGRA increases specificity, and ADA or IGRA increases sensitivity substantially.

The diagnostic value of T cell spot test and adenosine deaminase in pleural effusion for tuberculous pleurisy: A systematic review and meta-analysis

BACKGROUND

Tuberculous infection of T cell spot test (T-SPOT.TB) and adenosine deaminase (ADA) have a high diagnostic value in pleural effusion for tuberculous pleurisy. However, there were major differences in existing research in regard to the clinical application of the two trials. Therefore, we conducted a meta-analysis to systematically evaluate the diagnostic value of T-SPOT.TB and ADA.

METHODS

Pubmed, Web of Science and Embase databases were searched to compare diagnosis of tuberculous pleurisy by T-SPOT.TB and ADA. The search period was from inception to August 31, 2021. Statistical analyses were performed using Meta-disc 1.4, Revman 5.4 and Stata 16.0. Pooled sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), and diagnostic odds ratio (DOR) were determined. Summary receiver operating characteristic (SROC) curves and the area under the curve (AUC) were used to summarize overall diagnostic performance.

RESULTS

10 qualified original research studies were included, with a total of 2075 patients, of which were 1391 tuberculous pleurisy and 684 non-tuberculous pleurisy. The pooled estimates of diagnostic accuracy of T-SPOT.TB were as follows: sensitivity, 0.88 (95% CI: 0.86-0.90; I² = 92.7%); specificity, 0.79 (95% CI: 0.76-0.82; I² = 93.7%); PLR, 4.49 (95% CI: 2.29-8.80; I² = 94.9%); NLR, 0.15 (95% CI: 0.08-0.30; I² = 94.3%), DOR, 35.72 (95% CI: 11.15-114.47; I² = 91.5%). The AUC for SROC was 0.9283 (95% CI: 0.8912-0.9654). The pooled estimates of diagnostic accuracy of ADA were as follows: sensitivity, 0.65 (95% CI: 0.62-0.67; I² = 98.2%); specificity, 0.90 (95% CI: 0.88-0.92; I² = 69.4%); PLR, 6.12 (95% CI: 4.71-7.96; I² = 11.9%); NLR, 0.33 (95% CI: 0.12-0.89; I² = 99.5%), DOR, 23.18 (95% CI: 12.75-42.14; I² = 66.7%). The AUC for SROC was 0.9208 (95% CI: 0.9029-0.9387).

CONCLUSION

Both T-SPOT.TB and ADA had high value in the diagnosis of tuberculous pleurisy. The sensitivity of T-SPOT.TB was higher than ADA, but the specificity of ADA was higher than T-SPOT.TB. On the whole, T-SPOT. TB had similar diagnostic accuracy to ADA.

Comparison of the Diagnostic Accuracy of Xpert MTB/RIF and CapitalBio Mycobacterium RT-PCR Detection Assay for Tuberculous Pericarditis

Purpose

We evaluated CapitalBio Mycobacterium RT-PCR assay diagnosing tuberculous pericarditis (TBP), performed a head-to-head comparison with Xpert MTB/RIF, and assessed the impact of a parallel test (positive result for either of these two tests).

Methods

We reviewed suspected TBP patients with Xpert MTB/RIF, CapitalBio Mycobacterium RT-PCR assay, and Mycobacterium tuberculosis (MTB) culture. We analyzed sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and area under the curve (AUC).

Results

Seventy-four patients were included. Overall sensitivity, specificity, PPV, NPV, and AUC of CapitalBio Mycobacterium RT-PCR assay compared with culture were 50%, 91.1%, 64.3%, 85%, and 0.71, respectively. Overall sensitivity, specificity, PPV, NPV, and AUC of Xpert MTB/RIF for TBP were 61.1%, 91.1%, 68.8%, 87.9%, and 0.76. Parallel test values were 72.2%, 91.1%, 72.2%, 91.1%, and 0.82. The diagnostic accuracy of Xpert MTB/RIF was higher than CapitalBio Mycobacterium RT-PCR assay but was not significant (P > 0.05). The parallel test could improve diagnostic accuracy, but it was not significant compared to single tests (P > 0.05).

Conclusion

CapitalBio Mycobacterium RT-PCR assay had a moderate diagnostic accuracy, similar to Xpert MTB/RIF. The parallel test maximized diagnostic efficacy, but differences were not significant. CapitalBio Mycobacterium RT-PCR assay and Xpert MTB/RIF for TBP could be an initial option for early diagnosis.

The value of single or combined use of pleural fluid interferon gamma release assay in the diagnosis of tuberculous pleurisy

OBJECTIVE

Tuberculous pleurisy (TP) is a common disease of extrapulmonary tuberculosis, but its diagnosis is challenging. Recently, studies have found that the pleural fluid interferon gamma release assay (PF-IGRA) has important diagnostic value in TP, but the sample size of these studies was small, and the conclusions were inconsistent. Therefore, this study evaluated the diagnostic value of PF-IGRA in TP through a meta-analysis.

METHODS

We conducted a literature search in multiple databases to identify studies and calculated the sensitivity, specificity, positive likelihood ratio (PLR), negative likelihood ratio (NLR), diagnostic odds ratio (DOR), summary receiver operating characteristic (SROC) curve and area under the curve (AUC).

RESULTS

All 26 publications, including 30 case-control studies, were eventually included in the meta-analysis. The results showed that the pooled sensitivity, specificity, PLR, NLR, DOR and AUC with their 95% confidence intervals were 0.90 (0.88-0.91), 0.87 (0.85-0.89), 7.64 (4.46-13.07), 0.13 (0.09-0.19), 65.45 (32.13-133.33) and 0.9508, respectively. The subgroup analysis suggested that the sensitivity, specificity and AUC of PF-IGRA for TP in areas with a high tuberculosis burden were significantly higher than those in areas with a low tuberculosis burden. The sensitivity and AUC of the enzyme-linked immunosorbent assay method were higher than those of the enzyme-linked immunosorbent assay method for IGRA, but the specificity was similar. More importantly, PF-IGRA combined with adenosine deaminase (ADA) could increase the diagnostic value of TP.

CONCLUSIONS

The current meta-analysis indicated that PF-IGRA has high diagnostic value in diagnosing TP, especially in areas with a high TB burden. We recommended that the combination of PF-IGRA and ADA is the best way to diagnose TP.

Protein expression shift and potential diagnostic markers through proteomics profiling of tuberculous pleurisy biopsy tissues

OBJECTIVES

Tuberculous pleurisy is a common type of tuberculosis (TB), but its diagnosis is challenging. This study aimed to profile the protein expression of this disease and identify new diagnostic makers.

METHODS

Biopsy tissues from patients with tuberculous pleurisy and controls were taken through thoracoscopy, and proteins were extracted for Tandem Mass Tag Mass Spectrometry. Differential protein expression was performed between patients and controls, and the identified proteins were analyzed for pathway enrichment. Selected proteins were further validated in another set of samples using a more quantitative method.

RESULTS

A total of 5101 proteins were detected and quantified in a discovery set of patients and controls. Overall protein expression was quite different between patients and controls. Most proteins were down-expressed, while a minority were overly expressed in the patient samples. At p value < 0.05 and absolute fold change >2, 295 proteins were found to be up-expressed and 608 down-expressed. The top enriched pathways included ECM-receptor interaction, complement and coagulation cascades and focal adhesion. All 19 selected candidates were validated in an independent set of patient and control samples.

CONCLUSION

This unbiased proteomics approach not only provided unique insights into protein expression and pathways, but also discovered potential diagnostic markers for tuberculous pleurisy.

Development and validation of a novel scoring system developed from a nomogram to identify malignant pleural effusion

BACKGROUND

This study aimed to establish and validate a novel scoring system based on a nomogram for the differential diagnosis of malignant pleural effusion (MPE) and benign pleural effusion (BPE).

METHODS

Patients with PE and confirmed aetiology who underwent diagnostic thoracentesis were included in this study. One retrospective set (N = 1261) was used to develop and internally validate the predictive model. The clinical, radiological and laboratory features were collected and subjected to logistic regression analyses. The primary predictive model was displayed as a nomogram and then modified into a novel scoring system, which was externally validated in an independent set (N = 172).

FINDINGS

The novel scoring system was composed of fever (3 points), erythrocyte sedimentation rate (4 points), effusion adenosine deaminase (7 points), serum carcinoembryonic antigen (CEA) (4 points), effusion CEA (10 points) and effusion/serum CEA (8 points). With a cutoff value of 15 points, the area under the curve, specificity and sensitivity for identifying MPE were 0.913, 89.10%, and 82.63%, respectively, in the training set, 0.922, 93.48%, 81.51%, respectively, in the internal validation set and 0.912, 87.61%, 81.36%, respectively, in the external validation set. Moreover, this scoring system was exclusively applied to distinguish lung cancer with PE from tuberculous pleurisy and showed a favourable diagnostic performance in the training and validation sets.

INTERPRETATION

This novel scoring system was developed from a retrospective study and externally validated in an independent set based on six easily accessible clinical variables, and it exhibited good diagnostic performance for identifying MPE.

FUNDING

NFSC grants (no. 81572942, no. 81800094).

Rapid Decline of IFN-γ Spot-Forming Cells in Pleural Lymphocytes during Treatment in a Patient with Suspected Tuberculosis Pleurisy

A differential diagnosis of tuberculosis pleurisy is often difficult. A 48-year-old Japanese man with no previous medical history visited the outpatient department for dyspnea and fever. His chest-XP and laboratory findings, especially high C-reactive protein levels, indicated pleuritis with pleural effusion. Pleural lymphocytes showed high numbers of spot forming responses in interferon gamma release assay (IGRA). Pleural effusion contained high levels of adenosine deaminase and hyaluronic acid, but no Mycobacterium tuberculosis (TB) antigen was detected by culture or polymerase chain reaction (PCR). Although the infectious agent was not detected, the clinical and laboratory findings strongly suggested that he was suffering from tuberculosis pleurisy. After treatment with anti-TB drugs, a rapid decline of spot-forming cells (SFCs) of pleural lymphocyte was observed, despite persistently high levels of other biomarkers and increased pleural lymphocytes. This case demonstrates that an IGRA of pleural lymphocytes would be useful for therapeutic diagnosis for TB pleurisy suspected for TB.

Mycobacterium avium Complex Pleuritis with Elevated Anti-glycopeptidolipid-core IgA Antibody Levels in Pleural Effusion

Pleuritis caused by nontuberculous mycobacteria is uncommon and difficult to diagnose. We herein report a case of Mycobacterium avium complex (MAC) pleuritis with elevated anti-glycopeptidolipid (GPL)-core IgA antibody levels in the pleural effusion. A 73-year-old woman with MAC pulmonary disease presented with massive left pleural effusion. A pleural biopsy by video-assisted thoracoscopic surgery was performed, revealing many noncaseating epithelioid cell granulomas. MAC was not identified by culture of the pleural effusion or specimens, but the anti-GPL-core IgA antibody level was markedly elevated in the pleural effusion. Measurement of anti-GPL-core IgA levels in the pleural fluid may be useful for diagnosing MAC pleuritis.

Long-term efficacy of 6-month therapy with isoniazid and rifampin compared with isoniazid, rifampin, and pyrazinamide treatment for pleural tuberculosis

Research into anti-tuberculosis treatment has mainly focused on pulmonary tuberculosis (TB), with few studies on pleural-TB. The aim of the study is to compare the long-term efficacy of a 6-month treatment regimen with isoniazid and rifampicin (6HR) with treatment regimen of isoniazid, rifampicin, and pyrazinamide (6HR2Z) for pleural-TB. A case-control study of 200 HIV-negative patients with pleural-TB prospectively followed in our TB-unit from 1995 to 2018. The primary resistance to isoniazid is < 4% in our geographic area. Pleural-TB diagnosis was based on a positive culture for M. tuberculosis (84 patients), presence of caseating granulomas in pleural biopsy (28), or characteristics of pleural fluid (88). A comparative study of demographic and clinical characteristics between the treatment groups was carried out. Out of the 200 patients followed, (112 males, 88 females; mean age 32.9 ± 18.4 years), 99 patients were treated with 6HR regimen and 101 with 6HR2Z. The groups were comparable, except the 6HR2Z had larger size of pleural effusion. All patients completed the treatment. The group treated with 6HR presented fewer adverse effects (15.3%) than 6HR2Z group (33%), p = 0.005, and lower frequency of severe hepatic toxicity (5% vs 10.9%). Four patients died from causes other than TB during treatment with 6HR2Z, and all other patients were cured during a monitoring period for 8.4 years (IQRs, 3.3-14.3). Six patients in 6HR and 10 in 6HR2Z developed residual pachypleuritis. 6HR is as effective as 6HR2Z treatment for pleural-TB, with fewer adverse effects.

Medical thoracoscopy for tuberculous pleurisy: A retrospective analysis of 575 cases

OBJECTIVE

The objective of this retrospective study was to assess the efficacy of medical thoracoscopy in diagnosing of tuberculous pleurisy and characterize tuberculous pleurisy with medical thoracoscopy.

METHODS

A total of 575 patients with tuberculous pleurisy who underwent medical thoracoscopy were included in the study. Demographic data, clinical manifestations, and routine and biochemical tests on pleural fluid, cultures of pleural fluid, sputum, and pleural biopsy for the detection of Mycobacterium tuberculosis and pathological findings were evaluated.

RESULTS

Sputum, pleural fluid, and pleural biopsy cultures were positive for M. tuberculosis in 12.5%, 19.2%, and 41.9% of patients, respectively. Furthermore, there were significant differences in total positive tuberculosis (TB) tests in the pleural cavity according to patient's age (<18 years old, 50.0%; 18-34 years old, 50.2%; 35-59 years old, 34.8%; >60 years old, 18.6%; and all groups vs. >60 years old, P < 0.001). Patients with 18-34 years old were more likely to have granuloma in pleural biopsy specimens when compared to patients >60 years old (77.0% vs. 37.9%). The percentage of patients with high adenosine deaminase (ADA) levels in pleural fluid (>40 U/L), who were <18, 18-34, 35-59, and > 60 years old, was 83.3% (15/18), 72.8% (193/265), 51.2% (88/172), and 34.7% (17/49), respectively (all groups vs. >60 years old, P < 0.001).

CONCLUSION

Medical thoracoscopy is effective for diagnosing tuberculous pleurisy. Younger patients with tuberculous pleurisy have a higher number of positive TB tests in the pleural cavity, are more likely to have granuloma in pleural biopsy specimens, and have higher ADA levels in the pleural fluid.

Application of Venn's diagram in the diagnosis of pleural tuberculosis using IFN-γ, IP-10 and adenosine deaminase

BACKGROUND

Pleural tuberculosis (PlTB) is the most common extrapulmonary manifestation of this infectious disease which still presents high mortality rates worldwide. Conventional diagnostic tests for PlTB register multiple limitations, including the lack of sensitivity of microbiological methods on pleural specimens and the need of invasive procedures such as pleural biopsy performance. In this scenario, the search for biological markers on pleural fluid (PF) has been the target of several studies as a strategy to overcome the limitations of PlTB diagnosis. This study aims to evaluate the use either isolated or in combination with adenosine deaminase (ADA), interferon-gamma (IFN-γ), interferon-gamma inducible protein of 10-kD (IP-10) levels on PF in order to guide an accurate anti-TB treatment in microbiologically non-confirmed cases.

METHODS AND FINDINGS

Eighty patients presenting pleural effusion under investigation were enrolled in a cross-sectional study conducted at Pedro Ernesto University Hospital, Rio de Janeiro, RJ, Brazil. Peripheral blood (PB) and PF samples collected from all patients were applied to the commercial IFN-γ release assay, QuantiFERON-TB Gold In-Tube, and samples were analyzed for IFN-γ and IP-10 by immunoassays. ADA activity was determined on PF by the colorimetric method. Based on microbiological and histological criteria, patients were categorized as follow: confirmed PlTB (n = 16), non-confirmed PlTB (n = 17) and non-PlTB (n = 47). The Mycobacterium tuberculosis antigen-specific production of IFN-γ and IP-10 on PB or PF did not show significant differences. However, the basal levels of these biomarkers, as well as the ADA activity on PF, were significantly increased in confirmed PlTB in comparison to non-PlTB group. Receiver operating characteristics curves were performed and the best cut-off points of these three biomarkers were estimated. Their either isolated or combined performances (sensitivity [Se], specificity [Sp], positive predictive value [PPV], negative predictive value [NPV] and accuracy [Acc]) were determined and applied to Venn's diagrams among the groups. Based on the confirmed PlTB cases, IFN-γ showed the best performance of them at a cut-off point of 2.33 IU/mL (Se = 93.8% and Sp = 97.9%) followed by ADA at a cut-off of 25.80 IU/L (Se = 100% and Sp = 84.8%) and IP-10 (Cut-point = 4,361.90 pg/mL, Se = 75% and Sp = 82.6%). IFN-γ plus ADA (cut-point: 25.80 IU/L) represent the most accurate biomarker combination (98.4%), showing Se = 93.7%, Sp = 100%, PPV = 100% and NPV = 97.9%. When this analysis was applied in non-confirmed PlTB, 15/17 (88.2%) presented at least two positive biomarkers in combination.

CONCLUSION

IFN-γ, IP-10, and ADA in PlTB effusions are significantly higher than in non-PlTB cases. IFN-γ is an excellent rule-in and rule-out test compared to IP-10 and ADA. The combination of IFN-γ and ADA, in a reviewed cut-off point, showed to be particularly useful to clinicians as their positive results combined prompts immediate treatment for TB while both negative results suggest further investigation.