Diagnostic value of pleural fluid interferon-gamma and adenosine deaminase in patients with pleural tuberculosis in Qatar

Abstract

ObjectiveTo investigate the diagnostic utility of interferon-gamma (IFN-γ) and adenosine deaminase (ADA) in tuberculous pleural effusions by determining the best cutoff levels of these two markers for pleural tuberculosis, in the context of the local epidemiological settings in Qatar.MethodsWe prospectively studied IFN-γ and ADA levels in the pleural fluid of patients presenting to Hamad General Hospital between June 1, 2009 and May 31, 2010.ResultsWe studied 103 patients with pleural effusions, 72 (69.9%) with pleural tuberculosis, and 31 (30.1%) with nontuberculous etiologies. The mean IFN-γ concentration for the group with tuberculous effusions was significantly higher than that in the group with nontuberculous effusions (1.98 ± 81 vs 0.26 ± 10 pg/mL [P < 0.0001]). The mean ADA activity for the tuberculous effusions group was significantly higher than that in group with nontuberculous effusions (41.30 ± 20.09 vs 14.93 ± 14.87 U/L [P < 0.0001]). By analysis of receiver operating characteristic (ROC) curves, the best cutoff values for IFN-γ and ADA were 0.5 pg/mL and 16.65 U/L, respectively. The results for IFN-γ vs ADA were: for sensitivity, 100% vs 86%, respectively; for specificity, 100% vs 74%, respectively; for positive predictive value, 100% vs 88.5%, respectively; and for negative predictive value, 100% vs 69.7%, respectively.ConclusionIFN-γ and ADA could be used as valuable parameters for the differentiation of tuberculous from nontuberculous effusion, and IFN-γ was more sensitive and specific for tuberculous effusion than ADA.

Evaluation of immune cellular enzymes, oxidative and nitrosative Stress in Saudi Patients with Cutaneous Leishmaniasis in Al-AHssa, before and after treatment

“…The elevation of serum ADA activity in untreated CL patients may be attributed to the elevation of adenosine, the substrate of ADA which has been con rmed by other studies [10,40]. On the other hand, the increased serum ADA activity in patients with cutaneous leishmaniasis may be a re ection of induction of phagocytosis of macrophages and the increased cellular immunity by IFN-γ and IL-2, which are synthesized by Th1 cells [41].…”

Improving tuberculosis diagnostics with biomarkers

“…61 Biomarkers of immune response in PE have been proposed to assist in the rapid diagnosis of tuberculous PE while managing patients with PE of unknown etiology or while waiting for the results of mycobacterial culture. Pleural IFN-γ 62,63 and IFN-induced protein 10 (IP-10), 64 as well as adenosine deaminase (ADA), 65,66 have been reported to be useful markers for diagnosing tuberculous PE. Moreover, soluble FasL is released from T lymphocytes and exerts cytotoxic effects on Mtb-hidden macrophages, thereby helping in the diagnosis of tuberculous PE.…”

Increased soluble and membrane-bound PD-L1 contributes to immune regulation and disease progression in patients with tuberculous pleural effusion

“…TB-associated PF results from the infiltration of pleural space by M. tuberculosis (M. tb) antigens or bacilli, which induce a strong Th1 immune response (3). Currently, non-invasive methods including conventional chest X-ray, chest computed tomography scan, ultrasonography, pleural fluid laboratory tests, thoracocentesis, pleural biopsy and thoracoscopy are used to determine the existence and etiology of PFs (4). Pleural fluid M. tb culture remains the gold standard criterion with a diagnostic detection rate of <20% (5).…”