Occupational Exposure to Zoonotic Tuberculosis Caused by Mycobacterium caprae, Northern Greece, 2019.

Pulmonary tuberculosis caused by Mycobacterium caprae was diagnosed in a 65-year-old goat breeder from northern Greece. This case represents a documented occupational transmission of M. caprae and highlights the importance of enhanced laboratory screening and increased surveillance for zoonotic tuberculosis control.

Intracellular ESAT-6: A new biomarker for Mycobacterium tuberculosis infection.

BACKGROUND: Early secreted antigenic target 6 (ESAT-6) is a virulent factor of Mycobacterium tuberculosis (MTB). The identification of intracellular (i/c) ESAT-6 in host cells would be a direct marker of MTB infection. We developed a method to detect i/cESAT-6 by flow cytometry. The aim of this study is to investigate the expression of i/cESAT-6 in the host cells of individuals with MTB infection. METHODS: The expression of i/cESAT-6 was examined in the blood of 58 active TB patients, in 10 naïve to TB infection controls, in 17 patients who completed anti-TB treatment, and in 56 close contacts with an index TB case. Additionally, it was examined in the sputum of 12 active TB patients. RESULTS: The i/cESAT-6 was positively detected in the blood of 52 out of 58 (90%) active TB patients. All naïve to TB infection controls were negative. Three out of 17 (18%) patients at the end of anti-TB treatment were positive. Twenty-six out of 56 (46%) close contacts tested positive. The i/cESAT-6 was detected in all culture positive TB sputum specimens. CONCLUSIONS: The i/cESAT-6 is a promising biomarker of MTB infection that could be used in the evaluation of active TB patients and in the diagnosis of latent TB infection. Further studies are needed to validate its potential diagnostic role. © 2014 International Clinical Cytometry Society.

Flow cytometry analysis of CD4+IFN-γ+ T-cells for the diagnosis of mycobacterium tuberculosis infection.

BACKGROUND: CD4+ cells expressing Interferon-γ (IFN-γ), following stimulation with specific mycobacterial antigens, identified with flow cytometry (FCM-CD4+IFN-γ+), is a new method for the diagnosis of Mycobacterium tuberculosis (MTB) infection. The aim of this study is to investigate the performance of FCM-CD4+IFN-γ+ in comparison with tuberculin skin test (TST) and Quantiferon TB Gold In-Tube (QFT-G-IT) in the diagnosis of latent MTB infection (LTBI), in close contacts and in patients with rheumatic diseases under treatment with anti-TNFa and other biologic agents. METHODS: TST, QFT-G-IT, and FCM-CD4+IFN-γ+ were performed in 56 immunocompetent close contacts and in 65 medically immunosuppressed patients under biologic treatment. RESULTS: In close contacts, 63% were FCM-CD4+IFN-γ+ ESAT-6(+), 70% FCM-CD4+IFN-γ+ PPD(+), 41% QFT-G-IT(+) and 57% TST(+). FCM-CD4+IFN-γ+ ESAT-6 was the only test that was strongly correlated to the exposure time to infection. In the immunosuppressed group, 49% were FCM-CD4+IFN-γ+ ESAT-6(+), 62% FCM-CD4+IFN-γ+ PPD(+), 4.6% QFT-G-IT(+), and 18% TST(+). CONCLUSION: FCM-CD4+IFN-γ+ assays are more sensitive than QFT-G-IT and TST for the diagnosis of LTBI in close contacts and in immunosuppressed patients under anti-TNF-a treatment. FCM-CD4+IFN-γ+ is not affected by the chronic use of biologic agents. © 2015 International Clinical Cytometry Society.

Distribution of nontuberculous mycobacteria in treated patients with pulmonary disease in Greece - relation to microbiological data.

AIMS: The aim was to assess the distribution of nontuberculous mycobacteria (NTM) in treated patients with pulmonary disease (PD) in Greece. PATIENTS & METHODS: Patients treated for NTM PD at the two largest chest diseases hospitals in Greece, in the period 1990-2013 were investigated. For the years 2005-2013 data on NTM isolation frequency were recorded. RESULTS: M. avium complex (MAC) was the predominant cause of NTM PD disease followed by M. kansasii and rapid growing mycobacteria (RGM). The pathogenicity of RGM was significantly lower than this of MAC and M. kansasii. An increase was observed in the percentage of isolated NTM species that were considered clinically significant over the study period. CONCLUSIONS: The increasing number of NTM PD in Greece is a consequence of their isolation being more frequently considered as clinically relevant.

Cepheid GeneXpert MTB/RIF assay for Mycobacterium tuberculosis detection and rifampin resistance identification in patients with substantial clinical indications of tuberculosis and smear-negative microscopy results.

The GeneXpert MTB/RIF assay was evaluated with microscopically negative and positive pulmonary and extrapulmonary specimens from patients with substantial clinical indications for tuberculosis. For the pulmonary samples, the sensitivity, specificity, and positive and negative predictive values were 90.6%, 94.3%, 93.5%, and 91.7%, and for the extrapulmonary samples, they were 100%, 91.6%, 50%, and 100%, respectively. For microscopically negative specimens, the respective values were 86.3%, 93%, 79%, and 95.6%. The assay correctly detected rifampin resistance in all but one specimen, which harbored a mixed population. The GeneXpert assay was highly effective for tuberculosis diagnosis and identification of rifampin-resistant strains in smear-negative samples.

MIRU-VNTR typing of drug-resistant tuberculosis isolates in Greece.

The increasing immigration rate in Greece from countries with a high prevalence of Mycobacterium tuberculosis (MTB) and multidrug-resistant tuberculosis (MDR-TB) may have an impact οn the number of MDR-TB cases in Greece. The aim of this study was to genotypically characterize the MTB isolates from patients with pulmonary drug-resistant tuberculosis (DR-TB) in Greece, and to determine whether there is any association between the prevalent genotypes and drug resistance. Fifty-three drug-resistant MTB strains isolated from culture specimens of clinical material from native Greeks and immigrant patients with pulmonary tuberculosis were genotyped using the mycobacterial interspersed repetitive units-variable number of tandem repeats (MIRU-VNTR) method. The phylogenetically distinct groups of isolates identified were: the Beijing (34%), the LAM (11%), the Haarlem (24.5%), the Uganda I (9.4%), the Ural (3.8%), the Delhi/CAS (9.4%) and the Cameroon (3.8%) families. Greek patients were more likely to have monoresistant and polyresistant TB with the most prevalent isolates belonging to the Haarlem family. Among foreign-born patients with MDR-TB, the most prevalent genotypes belonged to the Beijing family. MIRU-VNTR rapidly obtained clinically useful genotyping data, by characterizing clonal MTB heterogeneity in the isolated strains. Our results underline the need for more effective antituberculosis control programs in order to control the expansion of DR-TB in Greece.

In vivo expression of innate immunity markers in patients with Mycobacterium tuberculosis infection.

BACKGROUND: Toll-like receptors (TLRs), Coronin-1 and Sp110 are essential factors for the containment of Mycobacterium tuberculosis infection. The purpose of this study was to investigate the in vivo expression of these molecules at different stages of the infection and uncover possible relationships between these markers and the state of the disease. METHODS: Twenty-two patients with active tuberculosis, 15 close contacts of subjects with latent disease, 17 close contacts of subjects negative for mycobacterium antigens and 10 healthy, unrelated to patients, subjects were studied. Quantitative mRNA expression of Coronin-1, Sp110, TLRs-1,-2,-4 and -6 was analysed in total blood cells vs an endogenous house-keeping gene. RESULTS: The mRNA expression of Coronin-1, Sp110 and TLR-2 was significantly higher in patients with active tuberculosis and subjects with latent disease compared to the uninfected ones. Positive linear correlation for the expression of those factors was only found in the infected populations. CONCLUSIONS: Our results suggest that the up-regulation of Coronin-1 and Sp110, through a pathway that also includes TLR-2 up-regulation may be involved in the process of tuberculous infection in humans. However, further studies are needed, in order to elucidate whether the selective upregulation of these factors in the infected patients could serve as a specific molecular marker of tuberculosis.