Impact of Implementation of an Automated Liquid Culture System on Diagnosis of Tuberculous Pleurisy

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.

Drug transdermal delivery by electrophonophoresis can increase the concentration of rifampicin in the pleural effusion of patients with tuberculous pleurisy but has no effect on the concentration of rifampicin in plasma

BACKGROUND

Electrophonophoresis (EP) has been widely used in various clinical fields. The purpose of this study was to evaluate the dermal permeability of rifampicin (RIF) in patients with tuberculous pleurisy assisted by EP and to verify the clinical application of this percutaneous drug delivery system in the treatment of tuberculous pleurisy, verify the system's influencing factors, and determine whether plasma drug concentration was increased.

METHOD

Patients were given oral isoniazid 0.3-0.4 g, rifampicin 0.45-0.60 g, pyrazinamide 1.0-1.5 g and ethambutol 0.75 g according to their body weight once a day. After 5 days of anti-tuberculosis treatment, 3 ml of rifampicin was delivered transdermally with EP. Pleural effusion and peripheral blood samples in patients were collected at and after dosing. The drug concentration in the samples was determined by high-performance liquid chromatography.

RESULT

The median plasma concentration (interquartile ranges) of RIF in 32 patients was 8.80 (6.65, 13.14) μg/ml before RIF transdermal injection plus EP and decreased to 8.09 (5.58, 11.82) μg/ml after 30 min of RIF transdermal injection plus EP. The RIF concentration in pleural effusion was higher than that before RIF-transdermal plus EP. In patients who received RIF via EP transdermal administration, the concentration of the drug at the local site was statistically higher than the concentration at the local site prior to penetration. However, no such enhancement was observed in plasma after transdermal administration of RIF.

CONCLUSION

EP can effectively increase the concentration of rifampicin in the pleural effusion of tuberculous pleurisy and has no effect on the circulating plasma concentration. The increased concentration of the drug in the lesion helps to destroy the bacteria.

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.

Central Venous Catheter Based Closed Thoracic Drainage in the Treatment of Tuberculous Pleuritis

Objective:

To explore the clinical effect of central venous catheter closed thoracic drainage in the treatment of tuberculous pleurisy.

Methods:

One hundred and four patients with tuberculous pleurisy who were admitted to Binzhou People’s Hospital from August 2016 to August 2017 were divided into a control group and a treatment group according to random number table method, 52 each. The control group was treated with conventional pleural puncture and drainage, while the treatment group was treated with closed central venous catheter based thoracic drainage. The clinical efficacy, improvement time of clinical symptoms, total volume of drainage, pleural thickness, and improvement of quality of life and occurrence of adverse reactions were compared between the two groups.

Results:

Pleural effusion, fever and chest tightness of the treatment group disappeared earlier (P<0.05); the hospitalization time in the treatment group was less than that in the control group (P<0.05); the total amount of drainage in the treatment group was lower than that in the control group (P<0.05); the pleural thickness of the treatment group was higher than that in the control group (P<0.05); the quality of life score in the treatment group was significantly higher than that in the control group (P<0.05). The total effective rates of the treatment group and the control group were 93.5% and 85%, respectively, with a significant difference (P<0.05). The incidence of adverse reactions in the treatment group was significantly lower than that in the control group, with a significant difference (P<0.05).

Conclusion:

Central venous catheter based closed thoracic drainage is more effective than conventional thoracic puncture and drainage in the treatment of tuberculous pleurisy. It can accelerate the improvement of clinical symptoms, improve the quality of life of patients, and reduce the incidence of complications. It is worth popularizing and applying.

Tuberculous pleural effusion: diagnosis & management

Background: Tuberculosis (TB) is the world's leading cause of death from infectious disease. The World Health Organization (WHO) recognized 6.3 million new TB cases in 2017, 16% corresponding to extrapulmonary forms; pleural tuberculosis (PT) is the most common extrapulmonary form in adults. PT diagnosis is often challenging because the scarcity of bacilli in pleural fluid (PF), sometimes requiring invasive procedures to obtain pleural tissue for histological, microbiological or molecular examination. In regions of medium and high disease prevalence, adenosine deaminase (ADA), interferon gamma (IFN-γ) and interleukin 27 (IL-27) dosages are useful to establish presumptive diagnosis in patients with compatible clinical/radiological picture who present with lymphocytic pleural effusion. PT treatment is similar to the pulmonary TB treatment regimen recommended by WHO. Area covered: In this update, we present a PT review, including epidemiology, pathogenesis, clinical features, diagnosis, and therapy. Expert opinion: There is no PF test alone accurate for PT diagnosis, despite the evolution in clinical laboratory. ADA, IFN-γ and IL-27 are valuable laboratory biomarkers; however, IFN-γ and IL-27 are quite expensive. Molecular tests present low sensitivity in PF, being useful for diagnostic confirmation. Multidrug therapy remains the PT treatment choice. Advancing research in immunotherapy may bring benefits to PT patients.

Tuberculous Pleural Effusion: Clinical Characteristics of 320 Patients

OBJECTIVES

To analyze the clinical and radiological characteristics and features of pleural fluid (PF) in patients with tuberculous pleural effusion (TPE).

METHODS

Retrospective analysis of TPEs treated in our clinic over the last 23years.

RESULTS

We included 320 patients with TPE (70% men; median age 33years). Mycobacterium tuberculosis was identified in the sputum or PF of 36% of the patients by microscopic examination, solid and liquid media cultures, or nucleic acid amplification tests. The greatest percentage of positive microbiological findings were associated with human immunodeficiency virus (HIV) co-infection (OR: 3.27), and with the presence in PF of proteins <4g/dL (OR: 3.53), neutrophils >60% (OR: 3.23), and glucose <40mg/dL (OR: 3.17). Pleural adenosine deaminase <35U/L was associated with TPEs that occupied less than half of the hemithorax (OR: 6.36) and with PF lactate dehydrogenase levels <500U/L (OR: 8.09). Radiological pulmonary opacities (30%) were more common in TPE occupying less than half of the hemithorax (OR: 2.73), in bilateral TPE (OR: 4.48), and in older patients (OR: 1.02). Factors predicting mortality were: HIV co-infection (OR: 24), proteins in PF <5g/dL (OR: 10), and greater age (OR: 1.05).

CONCLUSIONS

Patients with TPE and HIV co-infection and those with lower concentrations of proteins in PF had higher rates of positive microbiological results and death. Moreover, older patients had more pulmonary opacities and a higher incidence of death.

Diagnostic value of T-Spot TB combined with INF-γ and IL-27 in tuberculous pleurisy

The purpose of the present study was to investigate the diagnostic value of T cells spot test (T-Spot TB) combined with interferon-γ (INF-γ) and interleukin-27 (IL-27) in tuberculous pleurisy. Sixty patients with tuberculous pleurisy (observation group) and 60 patients with non-tuberculous pleurisy (control group) were enrolled in this study. T-Spot TB was performed to detect the pleural effusion of two groups of patients. Levels of IFN-γ and IL-27 in serum and pleural effusion were detected by enzyme-linked immunosorbent assay (ELISA). Relative expression of IFN-γ mRNA and IL-27 mRNA in peripheral blood mononuclear cells were detected by RT-PCR. Positive rate of T-Spot TB in observation group was 96.7% (58 cases), which was significantly higher than that in control group (p<0.05). Concentration of INF-γ in pleural effusion of observation group was 468.6±24.8 ng/l, which was significantly higher than that in control group (131.3±18.7 ng/l, p<0.05). Concentration of IL-27 in pleural effusion of observation group was 423.4±37.2 ng/l, which was significantly higher than that in control group (116.2±15.5 ng/l, p<0.05). Concentrations of INF-γ and IL-27 in serum of observation group were 48.2±13.4 and 41.7±10.6 ng/l, respectively, which were significantly higher than those in control group (38.6±11.2 and 35.3±8.4 ng/l, p<0.05). Relative expression levels of INF-γ mRNA and IL-27 mRNA in observation group were significantly higher than those in control group (p<0.05). Therefore, combination of T-Spot TB with INF-γ and IL-27 has significant application value in the clinical diagnosis of tuberculous pleurisy, and should be popularized.

Biomarkers in the diagnosis of pleural diseases: a 2018 update

The use of biomarkers on pleural fluid (PF) specimens may assist the decision-making process and enhance clinical diagnostic pathways. Three paradigmatic examples are heart failure, tuberculosis and, particularly, malignancy. An elevated PF concentration of the amino-terminal fragment of probrain natriuretic peptide (>1500 pg/ml) is a hallmark of acute decompensated heart failure. Adenosine deaminase, interferon-γ and interleukin-27 are three valuable biomarkers for diagnosing tuberculous pleurisy, yet only the first has been firmly established in clinical practice. Diagnostic PF biomarkers for malignancy can be classified as soluble-protein based, immunocytochemical and nucleic-acid based. Soluble markers (e.g. carcinoembryonic antigen (CEA), carbohydrate antigen 15-3, mesothelin) are only indicative of cancer, but not confirmatory. Immunocytochemical studies on PF cell blocks allow: (a) to distinguish mesothelioma from reactive mesothelial proliferations (e.g. loss of BAP1 nuclear expression, complemented by the demonstration of p16 deletion using fluorescence in situ hybridization, indicate mesothelioma); (b) to separate mesothelioma from adenocarcinoma (e.g. calretinin, CK 5/6, WT-1 and D2-40 are markers of mesothelioma, whereas CEA, EPCAM, TTF-1, napsin A, and claudin 4 are markers of carcinoma); and (c) to reveal tumor origin in pleural metastases of an unknown primary site (e.g. TTF-1 and napsin A for lung adenocarcinoma, p40 for squamous lung cancer, GATA3 and mammaglobin for breast cancer, or synaptophysin and chromogranin A for neuroendocrine tumors). Finally, PF may provide an adequate sample for analysis of molecular markers to guide patients with non-small cell lung cancer to appropriate targeted therapies. Molecular testing must include, at least, mutations of epidermal growth-factor receptor and BRAF V600E, translocations of rat osteosarcoma and anaplastic lymphoma kinase, and expression of programmed death ligand 1.

Does repeated pleural culture increase the diagnostic yield of Mycobacterium tuberculosis from tuberculous pleural effusion in HIV-negative individuals?

Background

Despite recent advances in methods for culturing Mycobacterium tuberculosis (MTB), the diagnostic yield of tuberculous pleural effusion (TBPE) remains unsatisfactory. However, unlike repeated sputum cultures of pulmonary tuberculosis, little is known about the role of repeated pleural cultures. We examined whether repeated pleural cultures are associated with increased MTB yield from TBPE.

Methods

A multicenter, retrospective cohort study was performed from January 2012 to December 2015 in South Korea. Patients were categorized into two groups: single- or repeated-culture groups. The diagnostic yield of MTB and clinical, radiological, and pleural fluid characteristics were evaluated.

Results

Among the 329 patients with TBPE, 77 (23.4%) had repeated cultures and 252 (76.5%) had a single culture. Pleural culture was performed twice in all 77 patients in the repeated-culture group at a 1-day interval (inter-quartile range, 1.0–2.0). In the repeated-culture group, the yield of MTB from the first culture was 31.2%, which was similar to that in the single-culture group (31.2% vs. 29.8%, P = 0.887). However, the yield of MTB from the second culture (10/77, 13.0%) was more than that from the first. These results may be attributable to the insufficient immune clearance for MTB invasion into the pleural space between the first and second cultures. Over time, the yield of the second cultures decreased from 17.4% to 6.7% and then 6.3%. Finally, the overall yield of MTB in the repeated- and single-culture groups was 44.2% and 29.8% respectively (P < 0.001).

Conclusions

The results showed that repeated pleural cultures increased MTB yield from TBPE in human immunodeficiency virus-negative individuals. Furthermore, repeated cultures may increase yield when carried out for two consecutive days.

Loculated Tuberculous Pleural Effusion: Easily Identifiable and Clinically Useful Predictor of Positive Mycobacterial Culture from Pleural Fluid

Background

Isolation of M. tuberculosis (MTB) is required in cases of Tuberculous pleural effusion (TBPE) for confirming diagnosis and successful therapy based on drug sensitivity test. Several studies have focused on predictors of MTB culture positivity in TBPE. However, the clinical role of loculated TBPE as a predictor of MTB cultivation from TBPE remains unclear. The aim of this study was to examine possible predictors including loculation of TBPE of MTB culture positivity in TBPE.

Methods

We retrospectively examined associations between clinical, radiological, microbiological, and laboratory characteristics and positive MTB culture from TBPE to determine a potent predictor of culture positivity.

Results

From January 2011 to August 2015, 232 patients with TBPE were identified. Of these, 219 were finally analyzed. Among them, 69 (31.5%) were culture positive for MTB in TBPE and 86 (39.3%) had loculated TBPE. In multivariate logistic regression analysis, the loculation of TBPE was independently associated with culture positivity for MTB in TBPE (adjusted odds ratio [OR], 40.062; 95% confidence interval [CI], 9.355–171.556; p<0.001). In contrast, the lymphocyte percentage of TBPE (adjusted OR, 0.934; 95% CI, 0.899–0.971; p=0.001) was inversely associated with culture positivity for MTB in TBPE.

Conclusion

In clinical practice, identification of loculation in TBPE is easy, reliable to measure, not uncommon and may be helpful to predict the possibility of positive mycobacterial culture.

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.

Diagnosis and Treatment of Nontuberculous Mycobacterial Lung Disease

Nontuberculous mycobacteria (NTM) are ubiquitous organisms; their isolation from clinical specimens does not always indicate clinical disease. The incidence of NTM lung diseases has been increasing worldwide. Although the geographic diversity of NTM species is well known, Mycobacterium avium complex (MAC), M. abscessus complex (MABC), and M. kansasii are the most commonly encountered and important etiologic organisms. Two distinct types of NTM lung diseases have been reported, namely fibrocavitary and nodular bronchiectatic forms. For laboratory diagnosis of NTM lung diseases, both liquid and solid media cultures and species-level identification are strongly recommended to enhance growth detection and determine the clinical relevance of isolates. Treatment for NTM lung diseases consists of a multidrug regimen and a long course of therapy, lasting more than 12 months after negative sputum conversion. For MAC lung disease, several new macrolide-based regimens are now recommended. For nodular bronchiectatic forms of MAC lung diseases, an intermittent three-time-weekly regimen produces outcomes similar to those of daily therapy. Treatment of MABC lung disease is very difficult, requiring long-term use of parenteral agents in combination with new macrolides. Treatment outcomes are much better for M. massiliense lung disease than for M. abscessus lung disease. Thus, precise identification of species in MABC infection is needed for the prediction of antibiotic response. Likewise, increased efforts to improve treatment outcomes and develop new agents for NTM lung disease are needed.