Original ArticleYield of pleural biopsy in different types of tubercular effusions
Introduction
Tuberculosis [TB] is the most common cause for exudative pleural effusions in areas where it is endemic. While it is the second most common form of extrapulmonary tuberculosis overall.1 Tubercular pleural effusions are usually considered to occur as a part of primary tuberculosis, but in adults it is shown to occur due to reactivation as well.2,3 Tubercular pleural effusion most often occur as a result of delayed hypersensitivity reaction to mycobacteria or its antigens if it occurs in association with primary tuberculosis.4 In reactivation it is usually an empyema and results secondary to rupture of an adjacent cavity or a paratracheal lymphnode, paravertebral abscess, osteomyelitis of adjacent bones or due to transdiaphragmatic spread. Tubercular empyema though severe are said to be less common than the simple effusion.4 The Gold standard for diagnosis of Tubercular pleural effusion is by the demonstration of mycobacterium tuberculosis in the sputum, pleural fluid, or pleural biopsy specimens.5 But microscopy of the pleural fluid for acid-fast bacilli is positive in only around 5% and mycobacterial culture is positive in about 24% of cases of TB effusions. This is probably due to the paucibacillary nature of the disease.6
GeneXpert for MTB has been validated in the diagnosis of smear positive PTB with a very high sensitivity (98%) and specificity (98%),7,8 but its role in smear-negative pulmonary tuberculosis and tubercular pleural effusions is still evolving.9 Few studies from sub-continent have shown a very low sensitivity in the pleural fluid and biopsy samples. Studies have shown that the biopsy obtained using medical thoracoscopy increases the yield in tubercular pleural effusions.10 Our study looked into the yield of thoracoscopy guided pleural biopsies in tubercular pleural effusions in terms of GeneXpert and mycobacterial culture. In addition, we also analysed the difference in the yield of MTB in biopsies from simple and complicated pleural effusion using medical thoracoscopy (semi-rigid and rigid thoracoscopy).
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Materials and methods
Medical thoracoscopy data of patients over last 5 years was collected, and retrospective analysis was done in Tubercular pleural effusions. Granulomatous inflammation on pleural biopsy was taken as the standard for the diagnosis of tuberculosis in our study. Data of 125 patients was analysed. Medical thoracoscopy was performed in the department of pulmonary medicine at Narayana Health City, Bangalore, India, between May-2015 and march-2020. Patients who had no/or minimal septations and no
Results
A total of 125 patients who were subjected to medical thoracoscopy had granulomatous lesions. 91 patients were male and 34 were female. Mean age was 42.3 ± 16.4 years and the mean ADA was 49.87 ± 19.0 iu. The basic demographics are presented in Table 1.
Among 61 patients with simple effusions who underwent semi-rigid thoracoscopy, 51 were male and 10 were female. The mean age was 48.3 ± 16.2 years. The mean ADA was 59.18 ± 26.7. Sixteen (33.3%) patients had diabetes mellitus (DM), 7 patients had
Discussion
Immune response to the MTB leads to the formation of granuloma in various tissues including the lung. The delicate balance between immune system and the mycobacterium keeps the growth of the bacteria under a check. Any disturbance in this balance leads to formation of caseation necrosis, disintegration of granuloma and release of MTB from the center to the adjacent tissues or spaces like pleural cavity. This results in an inflammatory response in the adjoining structures like pleura and
Conclusions
The yield of MTB increases as the pleural effusion becomes more complicated. GeneXpert in a pleural biopsy is a useful marker for MTB yield, especially in a complicated effusion as the drug resistance for MTB is on the rise. Rigid thoracoscopy should be considered in a complicated effusion as it has a good diagnostic yield as well as therapeutic benefit.
Source of funding
No funding received for this study.
Declaration of competing interest
All authors have none to declare.
Acknowledgements
The authors would like to acknowledge Dr. V.M. Annapandian, for his contribution in editing this manuscript. Dr. Tiyass Sen Dutt and Dr. B.R. Harish for assisting in procedures.
References (20)
- et al.
The prevalence of pulmonary parenchymal tuberculosis in patients with tuberculous pleuritis
Chest
(2006) - et al.
Diagnosis and treatment of tuberculous pleural effusion in 2006
Chest
(2007) - et al.
Tuberculous pleural effusion
J Thorac Dis
(2016) - et al.
Molecular epidemiology of pleural and other extrapulmonary tuberculosis: a Maryland state review
Clin Infect Dis
(2006) - et al.
Tuberculosis E-Book: A Comprehensive Clinical Reference
(2009) - et al.
Novel tests for diagnosing tuberculous pleural effusion: what works and what does not?
Eur Respir J
(2008) - et al.
Xpert® MTB/RIF assay for pulmonary tuberculosis and rifampicin resistance in adults
Cochrane Database Syst Rev
(2014) - et al.
Rapid molecular TB diagnosis: evidence, policy making and global implementation of Xpert MTB/RIF
Eur Respir J
(2013) - et al.
Diagnostic performance of xpert MTB/RIF in tuberculous pleural effusion: systematic review and meta-analysis
J Clin Microbiol
(2016) - et al.
Performance of Xpert MTB/RIF on pleural tissue for the diagnosis of pleural tuberculosis
Eur Respir J
(2013)
Cited by (0)
- c
Both authors contributed equally to the paper and procedures.
- d
Equally contributed in semi-rigid pleuroscopy.